/* Learn ESP32 — original implementation. Design language observed from the
   reference app; all code original. Fonts: Barlow / Barlow Semi Condensed /
   JetBrains Mono (SIL OFL). */
@font-face{font-family:Barlow;font-weight:400;font-display:swap;src:url(fonts/barlow-400.woff2)format("woff2")}
@font-face{font-family:Barlow;font-weight:500;font-display:swap;src:url(fonts/barlow-500.woff2)format("woff2")}
@font-face{font-family:Barlow;font-weight:600;font-display:swap;src:url(fonts/barlow-600.woff2)format("woff2")}
@font-face{font-family:"Barlow Semi Condensed";font-weight:500;font-display:swap;src:url(fonts/barlow-semi-condensed-500.woff2)format("woff2")}
@font-face{font-family:"Barlow Semi Condensed";font-weight:600;font-display:swap;src:url(fonts/barlow-semi-condensed-600.woff2)format("woff2")}
@font-face{font-family:"Barlow Semi Condensed";font-weight:700;font-display:swap;src:url(fonts/barlow-semi-condensed-700.woff2)format("woff2")}
@font-face{font-family:"JetBrains Mono";font-weight:400;font-display:swap;src:url(fonts/jetbrains-mono-400.woff2)format("woff2")}
@font-face{font-family:"JetBrains Mono";font-weight:500;font-display:swap;src:url(fonts/jetbrains-mono-500.woff2)format("woff2")}

:root{
  --bg:#f6eddd; --bg-deep:#efe3d1; --card:#f9f2e5; --card-soft:#faf4e9f7;
  --line:#cec0ad; --line-soft:#e2d7c7; --ink:#4f535b; --navy:#18213d;
  --muted:#696d74; --faint:#ada293; --teal:#1aa3a1; --teal-deep:#3f7f8e;
  --sidebar:#e9dcca; --trace:#d3bea3; --track:#e3d8ca; --code-bg:#f8f0e3;
  --kw:#2a56a3; --fn:#c0652d; --gutter:#aaa59d;
  --sans:"Barlow",system-ui,sans-serif;
  --cond:"Barlow Semi Condensed","Barlow",system-ui,sans-serif;
  --mono:"JetBrains Mono",ui-monospace,monospace;
  --console-h:92px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{-webkit-text-size-adjust:100%}
body{background:var(--bg);color:var(--ink);font-family:var(--sans);font-size:15px;line-height:1.45;overflow:hidden}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
a{color:inherit;text-decoration:none}
svg{display:block}
:focus-visible{outline:2px solid var(--teal);outline-offset:2px}

/* backdrop: diagonal grid + circuit traces */
.bg-grid{position:fixed;inset:0;pointer-events:none;
  background:
    repeating-linear-gradient(45deg,rgba(190,170,140,.13) 0 1px,transparent 1px 14px),
    repeating-linear-gradient(-45deg,rgba(190,170,140,.13) 0 1px,transparent 1px 14px),
    var(--bg);}
.bg-traces{position:fixed;inset:0;pointer-events:none;color:var(--trace);opacity:.55}

/* ============ loader ============ */
.loader{position:fixed;inset:0;z-index:60;background:var(--bg);display:flex;align-items:center;justify-content:center;transition:opacity .5s ease}
.loader.done{opacity:0;pointer-events:none}
.loader-inner{display:flex;flex-direction:column;align-items:center;gap:14px;width:min(320px,80vw)}
.loader-logo{width:92px;height:50px;color:var(--navy)}
.loader-logo .loop{fill:none;stroke:currentColor;stroke-width:5;stroke-linecap:round;
  stroke-dasharray:220;stroke-dashoffset:220;animation:draw 1.6s ease forwards}
.loader-logo .sign{fill:none;stroke:currentColor;stroke-width:5;stroke-linecap:round;
  stroke-dasharray:60;stroke-dashoffset:60;animation:draw 1s .8s ease forwards}
@keyframes draw{to{stroke-dashoffset:0}}
.loader-title{font-family:var(--cond);font-weight:700;font-size:22px;letter-spacing:.18em;color:var(--navy)}
.loader-track{width:100%;height:6px;border-radius:3px;background:var(--track);overflow:hidden;position:relative}
.loader-fill{position:absolute;inset:0;width:0%;background:var(--teal);border-radius:3px;transition:width .25s ease}
.loader-shine{position:absolute;inset:0;background:linear-gradient(100deg,transparent 30%,rgba(255,255,255,.55) 50%,transparent 70%);animation:shine 1.4s linear infinite}
@keyframes shine{from{transform:translateX(-100%)}to{transform:translateX(100%)}}
.loader-step{font-family:var(--mono);font-size:11px;color:var(--muted);letter-spacing:.06em}
.noscript{padding:16px;font-size:14px}

/* ============ app frame ============ */
#app{position:fixed;inset:0;display:flex;flex-direction:column;opacity:1}
#app[aria-hidden=true]{visibility:hidden}

.topbar{display:flex;align-items:center;gap:10px;padding:12px 14px 8px;flex-wrap:wrap;row-gap:10px}
.brand{display:flex;align-items:center;gap:10px;min-width:0;flex:1 0 100%}
.brand-logo{width:38px;height:22px;color:var(--navy);flex:none}
.brand-name{font-family:var(--cond);font-weight:700;font-size:16.5px;letter-spacing:.14em;color:var(--navy);line-height:1.05;white-space:nowrap}
.brand-tag{font-size:8px;letter-spacing:.26em;color:var(--faint);font-weight:500;margin-top:2px;white-space:nowrap}
.topbar-right{display:flex;align-items:center;gap:10px;flex:none;width:100%;justify-content:space-between}
.progress-pill{display:flex;align-items:center;gap:8px;background:var(--card);border:1px solid var(--line);border-radius:12px;padding:8px 12px;flex:0 1 240px;min-width:0}
.progress-pill .book{width:18px;height:18px;color:var(--navy)}
.progress-label{font-family:var(--cond);font-weight:600;font-size:12.5px;letter-spacing:.1em;color:var(--navy)}
.progress-bar{flex:1;min-width:40px;height:6px;border-radius:3px;background:var(--track);overflow:hidden}
.progress-fill{height:100%;width:0%;background:var(--teal);border-radius:3px;transition:width .4s}
.progress-count{font-family:var(--mono);font-size:11.5px;color:var(--navy);font-weight:500}
.clock{text-align:right;font-family:var(--mono);font-size:10.5px;color:var(--navy);line-height:1.35;white-space:nowrap}
.clock .date{letter-spacing:.06em}

.main{flex:1;display:grid;grid-template-columns:minmax(0,1fr);grid-template-rows:minmax(0,1fr) auto;min-height:0;position:relative;overflow:hidden}

/* stage */
.stage-wrap{grid-column:1;grid-row:1;min-height:0;position:relative;margin:2px 6px 2px;overflow:hidden}
#stage{position:absolute;inset:0;width:100%;height:100%;touch-action:none}
.stage-vignette{position:absolute;inset:0;pointer-events:none;box-shadow:inset 0 0 60px rgba(24,33,61,.06)}
.toolbar{position:absolute;left:50%;bottom:12px;transform:translateX(-50%);display:flex;gap:2px;background:var(--card);border:1px solid var(--line);border-radius:999px;padding:5px;box-shadow:0 2px 10px rgba(24,33,61,.08)}
.tool-btn{width:38px;height:38px;border-radius:999px;display:flex;align-items:center;justify-content:center;color:var(--navy)}
.tool-btn:hover{background:var(--bg-deep)}
.tool-btn.on{background:#dcebe4;color:var(--teal-deep)}
.tool-btn svg{width:19px;height:19px}

.stage-credit{position:absolute;left:50%;top:60%;transform:translate(-50%,-50%) rotate(-24deg);font-family:var(--mono);font-size:10.5px;letter-spacing:.06em;color:rgba(24,33,61,.13);pointer-events:none;white-space:nowrap}

/* callout tags overlay */
.tags{position:absolute;inset:0;pointer-events:none;overflow:hidden}
.tag{position:absolute;transform:translate(-50%,-50%);pointer-events:auto;cursor:pointer;
  background:var(--card);border:1px solid var(--line);border-radius:8px;padding:3px 9px;
  font-family:var(--cond);font-weight:600;font-size:11.5px;letter-spacing:.08em;color:var(--navy);
  box-shadow:0 1px 4px rgba(24,33,61,.12);white-space:nowrap;display:flex;align-items:center;gap:6px}
.tag::before{content:"";width:9px;height:9px;border-radius:50%;background:var(--teal);box-shadow:0 0 0 3px rgba(26,163,161,.25)}
.tag.live::before{background:#e8583f;box-shadow:0 0 0 3px rgba(232,88,63,.22)}
.tag:hover{border-color:var(--teal)}
.tag-leg{position:absolute;left:50%;top:100%;width:1px;background:var(--line);transform:translateX(-50%)}
.tag-ic{display:none}
.tag-tx i{display:none}
.tag-dot{display:none}
.leaders{position:absolute;inset:0;width:100%;height:100%;pointer-events:none;overflow:visible;display:none}
.leaders line{stroke:#41537a;stroke-opacity:.5;stroke-width:1.2;stroke-dasharray:1 5;stroke-linecap:round}

/* lesson info sheet (mobile bottom) / side panel (desktop) */
.panel{background:var(--card);border-top:1px solid var(--line)}
@media (max-width:1023px){
  .main{padding-bottom:48px}
  .stage-wrap{margin:6px 10px;border:1px solid var(--line);border-radius:18px;background:var(--bg)}
  .panel{position:absolute;left:0;right:0;bottom:0;z-index:15;border-radius:16px 16px 0 0;box-shadow:0 -8px 30px rgba(24,33,61,.14);transform:translateY(calc(100% - 42px));transition:transform .32s cubic-bezier(.32,.72,.28,1);max-height:78%;display:flex;flex-direction:column}
  .panel.open{transform:none}
  .panel-body{overflow-y:auto}
}
.tabbar{display:flex;gap:2px;padding:8px 12px 0;border-bottom:1px solid var(--line-soft)}
.tab{font-family:var(--cond);font-weight:600;font-size:13px;letter-spacing:.12em;color:var(--faint);padding:8px 10px 10px;border-bottom:2px solid transparent}
.tab.on{color:var(--navy);border-bottom-color:var(--navy)}
.panel-body{overflow-y:auto;-webkit-overflow-scrolling:touch}
.lesson-head{padding:14px 16px 4px}
.lesson-title{font-family:var(--cond);font-weight:700;font-size:22px;letter-spacing:.05em;color:var(--navy)}
.lesson-lede{padding:6px 16px 0;font-size:14.5px;color:var(--ink)}
.feature-list{list-style:none;padding:10px 16px 14px;display:flex;flex-direction:column;gap:9px}
.feature-list li{display:flex;gap:11px;align-items:flex-start;font-size:13.5px;color:var(--muted)}
.feature-list .fi{width:30px;height:30px;flex:none;border:1px solid var(--line);border-radius:8px;background:var(--bg);display:flex;align-items:center;justify-content:center;color:var(--teal-deep)}
.feature-list .fi svg{width:16px;height:16px}
.feature-list code,.lesson-lede code{font-family:var(--mono);font-size:.88em;color:var(--kw);background:#ece1cf;border-radius:4px;padding:0 4px}

/* pinout table */
.pinout{padding:12px 16px 16px;display:flex;flex-direction:column;gap:8px}
.pin-row{display:flex;gap:12px;align-items:baseline;border:1px solid var(--line-soft);background:var(--bg);border-radius:10px;padding:9px 12px}
.pin-chip{font-family:var(--mono);font-weight:500;font-size:12px;color:#fff;border-radius:6px;padding:2px 8px;min-width:74px;text-align:center}
.pin-name{font-family:var(--cond);font-weight:600;font-size:13.5px;letter-spacing:.06em;color:var(--navy);min-width:86px}
.pin-desc{font-size:13px;color:var(--muted)}

/* specs table */
.specs{padding:12px 16px 16px;display:flex;flex-direction:column}
.spec-row{display:flex;justify-content:space-between;gap:12px;padding:8px 2px;border-bottom:1px dashed var(--line-soft);font-size:13.5px}
.spec-row:last-child{border-bottom:0}
.spec-row b{font-family:var(--cond);font-weight:600;letter-spacing:.05em;color:var(--navy)}
.spec-row span{color:var(--muted);text-align:right}

/* example bullets */
.example{padding:10px 16px 16px;display:flex;flex-direction:column;gap:10px;font-size:14px}
.example p{color:var(--ink)}
.example code{font-family:var(--mono);font-size:.88em;color:var(--kw);background:#ece1cf;border-radius:4px;padding:0 4px}

/* code panel */
.code-card{margin:4px 16px 16px;border:1px solid var(--line);border-radius:12px;overflow:hidden;background:var(--code-bg)}
.code-head{display:flex;align-items:center;gap:8px;padding:8px 12px;border-bottom:1px solid var(--line-soft);background:var(--card)}
.code-title{font-family:var(--cond);font-weight:700;font-size:12.5px;letter-spacing:.14em;color:var(--navy)}
.code-actions{margin-left:auto;display:flex;gap:6px}
.icon-btn{width:30px;height:30px;border-radius:8px;border:1px solid var(--line);background:var(--bg);color:var(--navy);display:flex;align-items:center;justify-content:center}
.icon-btn svg{width:15px;height:15px}
.icon-btn.primary{background:var(--navy);border-color:var(--navy);color:#f6eddd}
.code-pre{font-family:var(--mono);font-size:12.5px;line-height:1.55;padding:10px 0;overflow-x:auto;color:var(--ink);direction:ltr;text-align:left}
.code-line{display:flex;white-space:pre}
.code-ln{width:34px;flex:none;text-align:right;padding-right:10px;color:var(--gutter);user-select:none}
.tok-kw{color:var(--kw);font-weight:500}.tok-fn{color:var(--fn)}.tok-num{color:#3f7f8e}.tok-str{color:#7a5c2e}.tok-com{color:var(--faint);font-style:italic}.tok-type{color:#6a4fa3}
/* console */
.console{height:var(--console-h);border-top:1px solid var(--line-soft);background:#f2e8d8;font-family:var(--mono);font-size:11.5px;padding:8px 12px;overflow-y:auto;color:var(--ink)}
.console .c-line{white-space:pre-wrap}
.console .c-sys{color:var(--faint)}
.console .c-hi{color:var(--teal-deep)}

/* lessons rail */
.lessons-sec{grid-column:1;grid-row:2;background:var(--card);border-top:1px solid var(--line);min-width:0;overflow:hidden}
.lessons-title{font-family:var(--cond);font-weight:700;font-size:14px;letter-spacing:.14em;color:var(--navy);padding:10px 16px 6px}
.lesson-rail{display:flex;gap:10px;overflow-x:auto;padding:2px 16px 12px;scroll-snap-type:x proximity;-webkit-overflow-scrolling:touch;min-width:0;align-items:stretch}
.lesson-rail::-webkit-scrollbar{display:none}
.lesson-card{scroll-snap-align:start;flex:none;width:min(68vw,260px);display:flex;flex-direction:row;align-items:center;gap:12px;border:1px solid var(--line);border-radius:12px;background:var(--bg);padding:8px 10px 8px 8px;text-align:left;position:relative}
.lesson-card.on{border-color:var(--teal);border-width:2px;padding:7px}
.lesson-card .thumb{width:78px;height:58px;flex:none;border-radius:8px;background:var(--bg-deep);object-fit:cover}
.lesson-card .lt{flex:1;font-family:var(--cond);font-weight:600;font-size:14px;letter-spacing:.06em;color:var(--navy);line-height:1.25;text-align:center}
.lesson-card .chev{position:static;flex:none;color:var(--faint)}
.lesson-card .done-badge{position:absolute;top:-6px;right:-6px;width:18px;height:18px;border-radius:50%;background:var(--teal);color:#fff;display:flex;align-items:center;justify-content:center}
.lesson-card .done-badge svg{width:11px;height:11px}
.rail-arrow{flex:none;align-self:center;width:30px;height:44px;border-radius:8px;color:var(--faint);display:flex;align-items:center;justify-content:center}

/* bottom nav */
.bottomnav{display:flex;border-top:1px solid var(--line);background:var(--card);padding:4px 4px calc(4px + env(safe-area-inset-bottom))}
.nav-btn{flex:1;display:flex;flex-direction:column;align-items:center;gap:3px;padding:6px 0;color:var(--muted);border-radius:12px;position:relative}
.nav-btn.on{color:var(--navy)}
.nav-btn.on::before{content:"";position:absolute;top:-7px;width:26px;height:3px;border-radius:2px;background:var(--teal)}
.nav-btn svg{width:21px;height:21px}
.nav-btn .nl{display:none}
.nav-badge{position:absolute;top:2px;right:calc(50% - 20px);background:var(--navy);color:#f6eddd;font-family:var(--mono);font-size:8px;border-radius:5px;padding:1px 4px}

/* sheets (components / settings / language) */
.sheet{position:absolute;left:0;right:0;bottom:0;max-height:72%;background:var(--card);border-top:1px solid var(--line);border-radius:16px 16px 0 0;display:flex;flex-direction:column;box-shadow:0 -8px 30px rgba(24,33,61,.14);z-index:20;transform:translateY(110%);transition:transform .32s cubic-bezier(.32,.72,.28,1)}
.sheet.open{transform:none}
.sheet-head{display:flex;align-items:baseline;padding:14px 16px 8px;border-bottom:1px solid var(--line-soft)}
.sheet-title{font-family:var(--cond);font-weight:700;font-size:16px;letter-spacing:.12em;color:var(--navy)}
.sheet-sub{margin-left:auto;font-size:12px;color:var(--faint)}
.sheet-body{overflow-y:auto;padding:6px 16px 20px}
.comp-row{display:flex;gap:12px;padding:10px 0;border-bottom:1px solid var(--line-soft);align-items:flex-start}
.comp-row:last-child{border-bottom:0}
.comp-ic{width:34px;height:34px;flex:none;border:1px solid var(--line);border-radius:9px;background:var(--bg);color:var(--teal-deep);display:flex;align-items:center;justify-content:center}
.comp-ic svg{width:18px;height:18px}
.comp-name{font-family:var(--cond);font-weight:700;font-size:13.5px;letter-spacing:.07em;color:var(--navy)}
.comp-desc{font-size:13px;color:var(--muted);margin-top:1px}

.set-row{display:flex;align-items:center;gap:12px;padding:11px 0;border-bottom:1px solid var(--line-soft)}
.set-row:last-child{border-bottom:0}
.set-name{font-family:var(--cond);font-weight:700;font-size:13px;letter-spacing:.08em;color:var(--navy)}
.set-desc{font-size:12.5px;color:var(--muted)}
.set-row .sp{flex:1}
.switch{width:44px;height:26px;border-radius:13px;background:var(--track);position:relative;transition:background .2s;flex:none}
.switch::after{content:"";position:absolute;top:3px;left:3px;width:20px;height:20px;border-radius:50%;background:#fff;box-shadow:0 1px 3px rgba(0,0,0,.25);transition:left .2s}
.switch.on{background:var(--teal)}
.switch.on::after{left:21px}
.select{appearance:none;border:1px solid var(--line);background:var(--bg);border-radius:9px;padding:7px 30px 7px 12px;font-family:var(--cond);font-weight:600;font-size:13px;color:var(--navy);
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath d='M1 1l4 4 4-4' stroke='%2318213d' fill='none' stroke-width='1.5'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 10px center}
.danger-btn{margin:14px 0 4px;border:1px solid var(--fn);color:var(--fn);border-radius:10px;padding:8px 16px;font-family:var(--cond);font-weight:600;font-size:12.5px;letter-spacing:.1em}

.lang-row{display:flex;align-items:center;gap:12px;width:100%;text-align:left;padding:10px 8px;border-radius:10px}
.lang-row.on{background:#dcebe4}
.lang-code{width:34px;height:34px;flex:none;border:1px solid var(--line);border-radius:9px;background:var(--bg);display:flex;align-items:center;justify-content:center;font-family:var(--mono);font-size:11px;color:var(--navy)}
.lang-row.on .lang-code{background:var(--teal);border-color:var(--teal);color:#fff}
.lang-native{font-family:var(--cond);font-weight:600;font-size:14.5px;letter-spacing:.07em;color:var(--navy)}
.lang-en{font-size:12px;color:var(--muted)}
.lang-check{margin-left:auto;color:var(--teal);width:18px;height:18px;visibility:hidden}
.lang-row.on .lang-check{visibility:visible}

/* credit */
.credit{position:fixed;left:6px;bottom:8px;z-index:8;font-size:9px;color:var(--faint);letter-spacing:.06em;writing-mode:vertical-rl;transform:rotate(180deg);display:none;max-height:42vh}

/* desktop layout */
.sidebar{display:none}
@media (max-width:480px){
  .tag{font-size:10px;padding:2px 7px;gap:4px}
  .tag::before{width:7px;height:7px;box-shadow:0 0 0 2px rgba(26,163,161,.25)}
  .topbar{gap:8px;padding:14px 14px 8px}
  .brand{gap:9px}
  .brand-logo{width:42px;height:24px}
  .brand-name{font-size:21px;letter-spacing:.14em}
  .brand-tag{font-size:9px;letter-spacing:.22em;margin-top:3px}
  .topbar-right{gap:8px}
  .progress-pill{gap:7px;padding:9px 12px}
  .progress-pill .book{width:19px;height:19px}
  .progress-label{font-size:13.5px}
  .progress-count{font-size:12.5px}
  .clock{font-size:11px}
}
@media (min-width:1024px){
  #app{display:grid;grid-template-columns:52px minmax(0,1fr);grid-template-rows:auto minmax(0,1fr)}
  .topbar{grid-column:1/3;padding:12px 18px 8px;flex-wrap:nowrap}
  .brand{flex:0 1 auto}
  .topbar-right{width:auto;margin-left:auto;justify-content:flex-end}
  .brand-logo{width:44px;height:26px}
  .brand-name{font-size:19px;letter-spacing:.16em}
  .brand-tag{font-size:9.5px;letter-spacing:.32em}
  .progress-bar{flex:none;width:110px}
  .clock{font-size:12px}
  .sidebar{display:flex;flex-direction:column;align-items:center;gap:4px;padding:8px 0;border-right:1px solid var(--line-soft)}
  .sidebar .nav-btn{flex:none;width:44px}
  .sidebar .nav-btn .nl{display:none}
  .main{grid-column:2;grid-row:2;grid-template-columns:minmax(0,1fr) 400px;grid-template-rows:minmax(0,1fr) auto}
  .stage-wrap{grid-column:1;grid-row:1;margin:0 0 4px 8px}
  .lessons-sec{grid-column:1;grid-row:2;margin:0 0 12px 14px;border:1px solid var(--line);border-radius:14px;overflow:hidden}
  .panel{grid-column:2;grid-row:1/3;margin:4px 12px 12px;display:flex;flex-direction:column;gap:12px;min-height:0;overflow:visible;background:transparent;border:0;border-radius:0}
  .panel-body{flex:none;overflow:visible;display:flex;flex-direction:column;gap:12px;min-height:0}
  .tabbar{background:var(--card);border:1px solid var(--line);border-radius:12px 12px 0 0}
  .tab-card{background:var(--card);border:1px solid var(--line);border-top:0;border-radius:0 0 12px 12px;max-height:44vh;overflow-y:auto}
  .code-card{margin:0;border-radius:12px}
  .code-pre{max-height:172px;overflow:auto}
  .bottomnav{display:none}
  .credit{display:block}
  .tag{white-space:normal;gap:8px;padding:8px 11px;border-radius:10px;max-width:210px;align-items:flex-start;box-shadow:0 3px 12px rgba(24,33,61,.10);font-family:var(--sans);font-weight:400;letter-spacing:0}
  .tag::before{display:none}
  .tag-ic{display:grid;place-items:center;width:25px;height:25px;flex:none;border:1px solid var(--line);border-radius:7px;background:var(--bg);color:var(--teal-deep)}
  .tag-ic svg{width:14px;height:14px}
  .tag-tx{display:block;min-width:0;text-align:start}
  .tag-tx b{display:block;font-family:var(--cond);font-weight:700;font-size:12px;letter-spacing:.08em;color:var(--navy);line-height:1.15}
  .tag-tx i{display:block;font-style:normal;font-size:11px;line-height:1.3;color:var(--muted);margin-top:2px}
  .tag-dot{display:block;position:absolute;width:9px;height:9px;border-radius:50%;background:var(--teal);box-shadow:0 0 0 3px rgba(26,163,161,.25);transform:translate(-50%,-50%);pointer-events:none}
  .leaders{display:block}
  .tag.mini{max-width:none;padding:3px 9px;border-radius:8px;align-items:center;gap:6px;white-space:nowrap;font-family:var(--cond);font-weight:600;font-size:11.5px;letter-spacing:.08em}
  .tag.mini::before{display:block}
  .tag.mini .tag-ic{display:none}
  .tag.mini .tag-tx i{display:none}
  .sheet{left:64px;right:auto;bottom:auto;top:100px;width:320px;max-height:calc(100% - 120px);border:1px solid var(--line);border-radius:14px;transform:translateX(-14px);opacity:0;visibility:hidden;transition:opacity .22s,transform .22s,visibility .22s}
  .sheet.open{transform:none;opacity:1;visibility:visible}
  [dir=rtl] .sheet{left:auto;right:64px}
}
@media (prefers-reduced-motion:reduce){
  *{animation-duration:.01ms !important;transition-duration:.01ms !important}
}

/* stage corner circuit traces */
.stage-corner{position:absolute;width:120px;height:120px;pointer-events:none;color:var(--trace);opacity:.8}
.stage-corner.tl{top:6px;left:6px}
.stage-corner.br{bottom:6px;right:6px;transform:rotate(180deg)}

/* lesson title row + fullscreen button */
.lesson-head{display:flex;align-items:center;padding:14px 16px 4px}
.lesson-head .fs-btn{margin-left:auto;flex:none}
/* fullscreen lesson panel */
.panel.full{position:fixed;inset:10px;z-index:45;border:1px solid var(--line);border-radius:14px;background:var(--card);display:flex;flex-direction:column;box-shadow:0 18px 60px rgba(24,33,61,.25);transform:none;max-height:none}
.panel.full .panel-body{flex:1;overflow-y:auto}
/* sidebar expand (desktop) */
@media (min-width:1024px){
  .sidebar .side-toggle{color:var(--faint)}
  #app.side-open{grid-template-columns:172px minmax(0,1fr)}
  .sidebar.expanded{align-items:stretch;padding:8px 8px;background:var(--sidebar)}
  .sidebar.expanded .nav-btn{flex-direction:row;gap:12px;width:100%;padding:10px 10px;align-items:center}
  .sidebar.expanded .nav-btn .nl{display:block;font-size:11px;letter-spacing:.08em;font-weight:600;font-family:var(--cond);color:var(--navy)}
}

/* schematic panel */
.schematic{position:absolute;top:12px;inset-inline-start:12px;width:min(400px,calc(100% - 24px));max-height:calc(100% - 24px);overflow:auto;border:1.5px solid var(--line);border-radius:12px;background:var(--card-soft);box-shadow:0 10px 26px -18px rgba(60,45,20,.6);z-index:6;display:none;flex-direction:column;padding:10px 12px 12px}
.schematic.is-on{display:flex;animation:.3s cubic-bezier(.2,.8,.2,1) schIn}
@keyframes schIn{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}
.sch-head{display:flex;align-items:baseline;gap:10px;padding:0 2px 6px;border-bottom:1px solid var(--line-soft)}
.sch-head h3{font-family:var(--cond);letter-spacing:.07em;color:var(--navy);margin:0;font-size:15px;font-weight:700}
.sch-lesson{flex:1;font-family:var(--cond);letter-spacing:.04em;text-transform:uppercase;color:var(--muted);font-size:13px;font-weight:500;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.sch-close{align-self:center;width:24px;height:24px;display:grid;place-items:center;border-radius:6px;border:0;background:none;cursor:pointer}
.sch-close:hover{background:rgba(36,48,74,.08)}
.sch-close svg{fill:none;width:15px;height:15px;stroke:var(--navy);stroke-width:2.2;stroke-linecap:round}
.sch-body{display:grid;place-items:center;padding-top:8px;min-height:0}
.sch-body svg{width:100%;height:auto;display:block}
.sch-none{color:var(--muted);margin:18px 0;font-size:14px}
.sch path,.sch circle,.sch rect{fill:none;stroke:#41537a;stroke-width:1.7px;stroke-linecap:round;stroke-linejoin:round}
.sch .solid{fill:#41537a;stroke:none}
.sch .fillable{fill:#41537a;fill-opacity:.85}
.sch .box{fill:#f3eadb}
.sch .ring{stroke:var(--line)}
.sch text{fill:var(--navy);stroke:none;font-family:var(--cond);letter-spacing:.03em;font-size:11px;font-weight:600}
.sch .block-t{letter-spacing:.08em;font-size:11.5px;font-weight:700}
.sch .pin-t{fill:#41537a;font-size:10.5px}
.sch .val{fill:var(--muted);font-weight:500}
.sch .note{fill:var(--muted);font-size:10.5px;font-weight:500}
.sch .sym-t{font-size:13px;font-weight:700}
.sch .pinval{letter-spacing:.05em;fill:var(--muted);font-size:9.5px;font-weight:700}
.sch .pinval.is-high{fill:#c9432f}
.sch .w{stroke:#41537a}

.part-tag{position:absolute;display:none;z-index:7;pointer-events:none;font-family:var(--cond);font-weight:700;font-size:11px;letter-spacing:.1em;text-transform:uppercase;color:var(--card);background:var(--navy);padding:4px 9px;border-radius:7px;white-space:nowrap}

/* reference-pattern spec tiles */
.specs{padding:4px 16px 16px;display:grid;grid-template-columns:1fr 1fr;gap:8px}
.spec-tile{border:1px solid var(--line);border-radius:10px;padding:8px 10px;background:var(--card)}
.spec-tile b{display:block;font-family:var(--cond);font-weight:600;font-size:10.5px;letter-spacing:.1em;color:var(--faint);margin-bottom:2px}
.spec-tile span{font-size:13px;color:var(--navy)}
/* active code line while the sketch runs: accent rail + emphasized gutter number */
.code-line{position:relative}
.code-line.active{background:rgba(15,118,110,.14);box-shadow:inset 3px 0 0 var(--teal-deep)}
.code-line.active .code-ln{color:#0f5f60;font-weight:700}
.code-ln{border-right:1px solid var(--line-soft);margin-right:10px}
/* code card fullscreen overlay */
.code-card.full{position:fixed;inset:10px;z-index:46;display:flex;flex-direction:column;background:var(--card);box-shadow:0 18px 60px rgba(24,33,61,.25)}
.code-card.full .code-pre{max-height:none;flex:1;overflow:auto}
.code-card.full .console{max-height:30vh}
/* rail tap arrows */
.rail-wrap{position:relative;display:flex;align-items:center;gap:4px}
.rail-wrap .lesson-rail{flex:1;min-width:0}
.rail-nav{flex:none;width:26px;height:44px;border:1px solid var(--line);border-radius:8px;background:var(--card);color:var(--faint);display:flex;align-items:center;justify-content:center;cursor:pointer}
.rail-nav:hover{color:var(--teal);border-color:var(--teal)}
/* Measured desktop shell: header, full-width lesson rail, compact view toolbar. */
@media(min-width:1024px){
  .topbar{min-height:94px;padding:14px 24px 12px 80px}
  .brand-logo{width:70px;height:42px}
  .brand-name{font-size:30px;letter-spacing:.15em}
  .brand-tag{font-size:13px;letter-spacing:.24em}
  .sidebar{grid-column:1;grid-row:1/3;z-index:3;padding-top:30px}
  .sidebar .nav-btn{min-height:60px}
  .sidebar .nav-btn[data-k=expand]{margin-bottom:12px}
  .main{grid-template-columns:minmax(0,1fr) 400px}
  .panel{grid-row:1;margin-top:4px}
  .lessons-sec{grid-column:1/3;margin:0 56px 16px 24px;border:0;border-radius:0;background:transparent}
  .lessons-title{padding:6px 0;font-size:14px}
  .lesson-rail{padding:2px 0 8px;gap:10px}
  .lesson-card{width:220px;height:74px;border-radius:7px}
  .lesson-card:first-child{width:260px}
  .lesson-card .thumb{width:62px;height:60px;background:transparent}
  .lesson-card:first-child .thumb{width:96px}
  .lesson-card .lt{font-size:13px}
  .toolbar{height:36px;padding:3px 8px;border-radius:9px;gap:3px;bottom:12px}
  .tool-btn{width:29px;height:28px;border-radius:5px}
  .tool-btn svg{width:16px;height:16px}
  .tabbar{padding-top:4px}
}
.code-pre{position:relative}
.sheet-body{min-height:0}
.sheet-head{flex-shrink:0}
@media(min-width:1024px){
 .topbar{grid-row:1;grid-column:2;padding-left:24px}
}
/* Parameter chips and a serial section that appears only during a simulation. */
[hidden]{display:none!important}
.code-param{color:var(--fn);font:inherit;border-bottom:1px dashed var(--teal);border-radius:3px;background:rgba(26,163,161,.08);cursor:pointer;padding:0 2px;line-height:inherit}
.code-param:hover{background:rgba(26,163,161,.2)}
.console-head{display:flex;align-items:center;gap:6px;padding:3px 9px;background:#efe4d2;border-top:1px solid var(--line);font-family:var(--cond);font-size:10px;letter-spacing:.07em}
.console-head b{text-transform:uppercase}
.console-head .icon-btn{margin-inline-start:auto;width:20px;height:18px;font-size:16px;border:0;background:transparent}
.serial-dot{width:6px;height:6px;border-radius:50%;background:var(--teal)}
.console{height:64px;font-size:10px;padding:4px 10px}
.icon-btn.is-running{background:#ce5c3c;border-color:#ce5c3c}
@media(min-width:1024px){
 .tab-card{min-height:276px}
 .code-pre{max-height:152px;font-size:12px}
 .code-head{padding:6px 8px;height:44px}
 .code-card{border-radius:9px}
}
@media(max-width:1023px){
 .topbar{min-height:128px}
 .stage-wrap{margin-top:6px}
 .toolbar{height:40px;padding:3px 7px;border-radius:9px;gap:5px;bottom:7px}
 .tool-btn{width:31px;height:30px;border-radius:5px}
 .tool-btn svg{width:18px;height:18px}
}
@media(min-width:1024px){.tag:not(.mini){width:200px;max-width:200px;flex-shrink:0}.tag-ic{border:0;background:transparent;color:var(--navy);width:23px}.tag-ic svg{width:20px;height:20px}}
@media(max-width:1023px){.nav-btn svg{width:23px;height:23px;stroke-width:2.2}.nav-btn.on svg{fill:var(--navy)}.progress-pill{flex-wrap:wrap}.progress-pill .progress-bar{order:4;flex:1;width:140px}.progress-pill .progress-count{order:5}}
@media(max-width:1023px){.sheet{left:10px;right:10px;bottom:18px;max-height:90%;border:1px solid var(--line);border-radius:13px}.sheet-body{padding:6px 16px 14px}.comp-row{border-bottom:0;padding-top:8px;padding-bottom:8px}.comp-name{font-size:15px}.comp-desc{font-size:14px}}
@media(max-width:1023px){.sheet:not(.open){visibility:hidden}.sheet.open{visibility:visible}}
.lesson-card .thumb{object-fit:contain;background:transparent}
@media(max-width:1023px){
 .topbar{padding:14px 12px 6px;row-gap:12px;min-height:128px}
 .brand{gap:9px}.brand-logo{width:65px;height:36px}.brand-name{font-size:21px;font-weight:600;letter-spacing:.14em}.brand-tag{font-family:var(--mono);font-size:10px;letter-spacing:.1em;margin-top:4px}
 .progress-pill{display:grid;grid-template-columns:30px minmax(80px,1fr) auto;grid-template-rows:auto 10px;column-gap:10px;row-gap:2px;padding:7px 12px;border-radius:9px;flex-basis:250px}
 .progress-pill .book{grid-column:1;grid-row:1/3;width:26px;height:26px}
 .progress-pill .progress-label{grid-column:2/4;grid-row:1;font-size:14px;letter-spacing:0}
 .progress-pill .progress-bar{grid-column:2;grid-row:2;order:initial;width:100%;height:9px}
 .progress-pill .progress-count{grid-column:3;grid-row:2;order:initial;font-size:13px;line-height:10px}
 .clock{font-size:12px;line-height:1.35}
 .stage-corner{display:none}.toolbar{padding-inline:10px;gap:6px;min-width:286px}
 .stage-wrap{margin-inline:12px;border-radius:14px}
}

/* Independent drafting surface: fixed isometric spacing, distinct from the page backdrop. */
.stage-wrap{background-color:var(--bg);background-image:repeating-linear-gradient(26deg,transparent 0 25px,rgba(183,153,108,.3) 25px 26px),repeating-linear-gradient(136deg,transparent 0 28px,rgba(183,153,108,.3) 28px 29px);background-position:center}
.stage-wrap.no-grid{background-image:none}
@media(max-width:1023px){
 .bg-grid{background:var(--bg)}
 .tag:not(.live):not(#partTag){padding:3px 7px;border-radius:6px;font-size:11px;letter-spacing:.045em;line-height:1.3}
 .tag:not(.live):not(#partTag)::before{display:none}
 .tag-dot{position:absolute;width:15px;height:15px;border-radius:50%;border:3px solid var(--teal);background:#e8fff6;box-shadow:0 0 0 1px rgba(24,33,61,.25);transform:translate(-50%,-50%);pointer-events:none;z-index:1}
}

@media(max-width:1023px){
 .lesson-rail{padding-inline:12px;gap:12px}
 .lesson-card{width:198px;height:74px;border-radius:8px;scroll-snap-align:center;padding:7px;gap:8px}
 .lesson-card:first-child{width:252px}
 .lesson-card .thumb{width:60px;height:60px}
 .lesson-card:first-child .thumb{width:96px;height:64px}
 .lesson-card .lt{font-size:14px;letter-spacing:.035em;text-align:start}
 .lesson-card.on{border-color:var(--teal-deep)}
 .lesson-card.on .chev{color:var(--teal-deep)}
}

@media(max-width:1023px){.lesson-card .lt{flex:none;max-width:118px;font-size:14px;white-space:normal}.lesson-card:not(:first-child){gap:8px}.lesson-card:not(:first-child) .thumb{width:45px}.lesson-card:not(:first-child) .lt{white-space:nowrap}.lesson-card:first-child .lt{max-width:114px}}

@media(max-width:1023px){.rail-wrap{position:relative;display:block}.rail-nav{position:absolute;top:calc(50% - 15px);z-index:2;background:var(--card);width:30px;height:30px;border-radius:50%}.rail-nav:first-child{left:0}.rail-nav:last-child{right:0}.lesson-rail{scroll-snap-type:none}.lesson-card .chev{margin-inline-start:auto}}

/* The carousel arrows have opaque edge wells, so adjacent clipped cards do not print under them. */
@media(max-width:1023px){.rail-wrap::before,.rail-wrap::after{content:"";position:absolute;top:0;bottom:0;width:36px;z-index:2;pointer-events:none}.rail-wrap::before{left:0;background:linear-gradient(90deg,var(--card) 0 26px,transparent)}.rail-wrap::after{right:0;background:linear-gradient(270deg,var(--card) 0 26px,transparent)}.rail-nav{z-index:3}}

@media(max-width:1023px){.lesson-card.edge-cut .lt{visibility:hidden}.tool-btn:nth-child(2),.tool-btn:nth-child(4),.tool-btn:nth-child(5){position:relative}.tool-btn:nth-child(2)::after,.tool-btn:nth-child(4)::after,.tool-btn:nth-child(5)::after{content:"";position:absolute;right:-4px;height:18px;width:1px;background:var(--line)}}

/* On phones the reference is a document, not a bottom-sheet workspace. */
@media(max-width:1023px){
 body{overflow:auto}
 #app{position:relative;inset:auto;min-height:100dvh;padding-bottom:calc(72px + env(safe-area-inset-bottom));overflow:visible}
 .main{display:flex;flex:none;flex-direction:column;overflow:visible;min-height:0;padding-bottom:0}
 .stage-wrap{flex:none;order:0;height:58vh;min-height:360px;margin-top:6px;margin-bottom:6px}
 .lessons-sec{flex:none;order:1;border:0;background:transparent;padding-bottom:0;overflow:hidden}
 .lessons-title{padding:5px 12px 6px;letter-spacing:.04em;font-size:16px}
 .lesson-rail{padding-bottom:12px}
 .panel,.panel.open{order:2;position:relative;inset:auto;margin:0 12px;z-index:auto;transform:none;transition:none;max-height:none;border:0;border-radius:0;box-shadow:none;background:transparent;display:block}
 .tabbar{border:1px solid var(--line);border-bottom:1px solid var(--line-soft);border-radius:12px 12px 0 0;background:var(--card);padding:7px 4px 0;gap:0;justify-content:space-around}
 .tab{padding:8px 5px 11px;font-size:14px;letter-spacing:.035em}
 .panel-body{overflow:visible;display:flex;flex-direction:column;gap:12px}
 .tab-card{border:1px solid var(--line);border-top:0;border-radius:0 0 12px 12px;background:var(--card);height:345px;overflow:auto}
 .code-card{margin:0;border-radius:10px;flex:none}
 .code-pre{max-height:225px;font-size:12px}
 .code-head{height:49px}
 .lesson-head .fs-btn,#btnCodeFs{display:none}
 .bottomnav{position:fixed;inset:auto 0 0;z-index:35;min-height:62px;align-items:center}
 .nav-btn{border-radius:0}.nav-btn.on::before{display:none}
 .sheet{position:fixed;bottom:76px;max-height:calc(100dvh - 100px)}
 .panel.full{position:fixed;inset:10px;z-index:45;margin:0;display:flex;max-height:none}
 .panel.full .tab-card{height:auto;overflow:visible}
 .panel.full .panel-body{overflow:auto}
}
/* Numbered explanations remain original ESP32 teaching content. */
.example{list-style:none;counter-reset:ex}
.example li{position:relative;padding-inline-start:42px;min-height:30px;counter-increment:ex}
.example li::before{content:counter(ex);position:absolute;inset-inline-start:0;top:0;width:29px;height:29px;border:1px solid var(--line);border-radius:7px;display:flex;align-items:center;justify-content:center;font-family:var(--cond);font-weight:600;color:var(--navy)}
@media(max-width:1023px){
 .tabbar{height:58px;align-items:stretch;padding-inline:6px}
 .tab{font-size:15px;font-weight:500;letter-spacing:.02em}.tab.on{font-weight:700}
 .tab-card{border-radius:9px;margin:0 4px 4px;border:1px solid var(--line);height:345px}
 .panel-body{border:1px solid var(--line);border-top:0;border-radius:0 0 12px 12px;gap:0;background:var(--card)}
 .lesson-head{padding:12px 15px 4px}.lesson-title{font-size:22px;letter-spacing:.015em}
 .example{font-size:16px;line-height:1.4;padding:9px 15px 15px;gap:13px}
 .example code{font-size:.84em}
 .code-card{margin:12px -1px -1px;border-radius:10px;padding:0 8px 8px;background:var(--card)}
 .code-head{height:55px;padding:6px 8px;border:0}
 .code-title{font-size:17px;letter-spacing:.035em}
 .code-actions{gap:8px}.code-actions .icon-btn{width:40px;height:38px;border-radius:8px}.code-actions .icon-btn.primary{width:44px;background:#2c3d67;border-color:#2c3d67}
 .code-actions .icon-btn.primary.is-running{background:#c5523c;border-color:#c5523c}
 .code-actions .icon-btn svg{width:19px;height:19px}
 .code-pre{font-size:14px;line-height:1.55;max-height:335px;border:1px solid var(--line);border-radius:8px;padding:10px 0;background:var(--code-bg)}
 .code-ln{width:43px;padding-right:12px;border-right:1px solid var(--line-soft);margin-right:10px}
 .console-head{margin-top:0;font-size:12px;padding:4px 8px}
 .console{height:76px;font-size:12px;padding:6px 10px}
 .bottomnav{background:#eadecc}.nav-btn{color:#747980}
}
@media(max-width:1023px){
 .rail-wrap:not(.can-left)::before,.rail-wrap:not(.can-right)::after{display:none}
 .panel-body{display:contents}
 .tab-card{margin:0;padding-top:0;border-radius:0 0 12px 12px;border:1px solid var(--line);border-top:0}
 .code-card{margin:12px 0 0}
 .code-card.full{padding-top:0}
 .example li{color:var(--ink)}
}
@media(max-width:1023px){
 .tab-card{height:auto;overflow:visible;padding:0 3px 3px}
 .info-content{height:345px;overflow:auto;border:1px solid var(--line);border-radius:10px}
 .tabbar{border-bottom:0}
 .panel.full .info-content{height:auto;overflow:visible}
}
@media(max-width:1023px){.tabbar{overflow-x:auto;justify-content:space-between;scrollbar-width:none}.tabbar::-webkit-scrollbar{display:none}.tab{flex:none}.tab.on:focus:not(:focus-visible){outline:none}}
.example code,.lesson-lede code,.feature-list code{direction:ltr;unicode-bidi:isolate;display:inline-block}
.tab:focus:not(:focus-visible){outline:none}
@media(max-width:1023px){.bottomnav .nav-btn:nth-child(-n+4){color:#2b3d62}.bottomnav .nav-btn[data-k=home] svg{fill:currentColor;stroke:none}.bottomnav .nav-btn[data-k=lessons] svg,.bottomnav .nav-btn[data-k=comp] svg{stroke-width:1.8}.bottomnav .nav-btn[data-k=play] svg path{fill:currentColor}}

@media(max-width:1023px){.bottomnav .nav-btn.on{border-radius:12px;background:#d4ccbf}.bottomnav .nav-btn.on::after{content:"";position:absolute;bottom:-8px;width:26px;height:3px;border-radius:2px;background:var(--teal)}.bottomnav .nav-btn.on svg{fill:none}.bottomnav .nav-btn.on[data-k=home] svg{fill:currentColor}.bottomnav .nav-btn.on[data-k=play] svg path{fill:currentColor}}
/* Compact laptop popovers and consistent information-card height. */
@media(min-width:1024px){
 .sheet{width:245px;border-radius:9px;max-height:456px}
 .sheet-head{padding:10px 13px 8px}.sheet-title{font-size:13px}.sheet-body{padding:4px 13px 10px}
 .comp-row{padding:7px 0;gap:8px}.comp-name{font-size:11.5px}.comp-desc{font-size:11.5px;line-height:1.3}
 .set-row{padding:8px 0;gap:8px}.set-name{font-size:11.5px}.set-desc{font-size:11.5px;line-height:1.3}
 .set-row .select{max-width:110px;padding:4px 8px;font-size:11px}.switch{width:31px;height:18px}.switch:after{width:14px;height:14px}.switch.on:after{transform:translateX(13px)}
 .tag:not(.mini){width:190px;max-width:190px;padding:10px 12px;box-shadow:none;border-radius:5px}
 .tag-tx b{font-size:12px}.tag-tx i{font-size:12px;line-height:1.25}
}
@media(min-width:1024px){.switch::after{top:2px;left:2px;transform:none}.switch.on::after{left:15px;transform:none}}
/* Laptop information shell: stable nested card and inset code surface. */
@media(min-width:1024px){
 .topbar-right{border:1px solid var(--line-soft);border-radius:10px;padding:7px 12px 7px 7px;gap:18px}
 .progress-pill{display:grid;grid-template-columns:30px minmax(60px,1fr) auto;grid-template-rows:auto 10px;column-gap:10px;row-gap:2px;width:205px;flex:none;padding:8px 12px;border-radius:7px}
 .progress-pill .book{grid-column:1;grid-row:1/3;width:27px;height:27px}
 .progress-pill .progress-label{grid-column:2/4;grid-row:1;letter-spacing:.02em}
 .progress-pill .progress-bar{grid-column:2;grid-row:2;width:100%;height:9px;min-width:0}
 .progress-pill .progress-count{grid-column:3;grid-row:2;line-height:10px}
 .clock{font-size:13px}
 .panel{gap:0}.tabbar{border-bottom:0;padding:4px 8px 0}.tab{font-size:14px;letter-spacing:.035em;padding:8px 8px 10px}
 .panel-body{gap:8px}.tab-card{height:278px;min-height:278px;max-height:none;padding:0 3px 3px;overflow:visible}
 .info-content{height:274px;overflow:auto;border:1px solid var(--line);border-radius:9px}
 .lesson-head{padding:12px 14px 3px}.lesson-title{font-size:21px;letter-spacing:.015em}
 .code-card{padding:0 8px 8px;background:var(--card)}.code-head{padding-inline:6px;border:0}.code-title{font-size:14px;letter-spacing:.035em}
 .code-pre{border:1px solid var(--line);border-radius:7px;background:var(--code-bg)}
 .panel.full .tab-card{height:auto;min-height:0}.panel.full .info-content{height:auto;overflow:visible}.code-card.full{padding-top:0}
}
@media(min-width:1024px){.code-card:not(.full):has(.console:not([hidden])) .code-pre{max-height:64px}}

/* Original etched circuit frame, kept behind all controls. */
@media(min-width:1024px){.bg-grid{background:var(--bg)}.bg-traces{width:100%;height:100%;opacity:.8}.stage-corner{display:none}.stage-wrap{background-image:repeating-linear-gradient(26deg,transparent 0 25px,rgba(183,153,108,.21) 25px 26px),repeating-linear-gradient(136deg,transparent 0 28px,rgba(183,153,108,.21) 28px 29px)}.stage-vignette{box-shadow:inset 0 0 75px 30px var(--bg)}}
@media(max-width:1023px){.bg-traces{display:none}}

/* Desktop navigation uses an inset selection tile, not the phone underline. */
@media(min-width:1024px){
 .sidebar .nav-btn{color:#70747b;justify-content:center}
 .sidebar .nav-btn:nth-child(-n+5){color:#2b3d62}
 .sidebar .nav-btn svg{width:21px;height:21px;stroke-width:1.9}
 .sidebar .nav-btn.on::before{top:50%;left:50%;transform:translate(-50%,-50%);width:36px;height:36px;border-radius:5px;background:#d4ccbf;z-index:-1}
 .sidebar .nav-btn[data-k=play] svg path{fill:currentColor;stroke:none}
 .sidebar .side-toggle{min-height:38px;height:38px;width:36px;border:1px solid var(--line);border-radius:8px;background:#f0e6d7b3;margin-bottom:18px}
 .sidebar .nav-badge{top:calc(50% + 3px);right:4px;font-size:7px;padding:1px 2px;line-height:1}
 .sidebar.expanded .nav-btn{justify-content:flex-start}
 .sidebar.expanded .nav-btn.on::before{width:calc(100% - 2px)}
 .sidebar.expanded .nav-badge{right:7px}
}
/* Expanding navigation overlays the drafting page without moving the circuit. */
@media(min-width:1024px){
 #app.side-open{grid-template-columns:52px minmax(0,1fr)}
 .sidebar.expanded{position:absolute;inset:0 auto 0 0;width:180px;z-index:30;box-shadow:4px 0 12px rgba(60,45,20,.12);padding:30px 8px 8px}
 .sidebar.expanded .side-toggle{width:36px;justify-content:center;padding:6px 0}
 .sidebar.expanded .nav-btn .nl{text-transform:uppercase}
}

.view-hint{display:none}
@media(min-width:1024px){.view-hint{position:absolute;bottom:60px;left:50%;transform:translateX(-50%);background:var(--navy);color:var(--card);font:600 11px var(--cond);padding:3px 7px;border-radius:7px;white-space:nowrap;pointer-events:none;z-index:8}.stage-wrap:has(.toolbar:hover) .view-hint,.stage-wrap:has(.toolbar:focus-within) .view-hint{display:block}}
/* Pin identities stay beside their names, with descriptions on their own row. */
@media(max-width:1023px){.pin-row{display:grid;grid-template-columns:minmax(0,auto) minmax(0,1fr);gap:6px 10px}.pin-chip{min-width:0;max-width:100%;overflow-wrap:anywhere}.pin-name{min-width:0;overflow-wrap:anywhere}.pin-desc{grid-column:1/-1;min-width:0;overflow-wrap:anywhere}}
@media(max-width:360px){.pin-row{grid-template-columns:minmax(0,1fr)}.pin-chip{justify-self:start}.pin-name,.pin-desc{grid-column:1}}

.console-grip{height:5px;flex:none;cursor:ns-resize;touch-action:none;background:var(--code-bg);position:relative;border-top:1px solid var(--line-soft)}
.console-grip::after{content:"";position:absolute;width:24px;height:2px;background:var(--line);left:calc(50% - 12px);top:1px;border-radius:2px}

@media(min-width:1024px){.schematic{width:340px;padding:8px 10px 10px;top:6px}.sch-head h3{font-size:13px}.sch-lesson{font-size:11px}}

/* Circuit geometry and pin identifiers stay left-to-right inside RTL interfaces. */
.sch{direction:ltr}

.sheet-close{flex-shrink:0;margin-left:10px;width:30px;height:30px;border:1px solid var(--line-soft);border-radius:6px;background:transparent;color:var(--navy);font-size:23px;line-height:1;cursor:pointer}.sheet-close:focus-visible{outline:2px solid var(--teal);outline-offset:2px}
.sheet-head{flex-wrap:wrap;align-items:center;gap:4px}.sheet-title{flex:1}.sheet-sub{order:3;flex-basis:100%;margin-left:0}.sheet-close{margin-left:6px}
/* Native switch keeps pointer, keyboard and screen-reader semantics. */
#heatPower{appearance:none;position:relative;flex-shrink:0;width:36px;height:22px;border-radius:12px;background:var(--track);border:1px solid var(--line);cursor:pointer;transition:background .15s}
#heatPower:before{content:"";position:absolute;width:16px;height:16px;left:2px;top:2px;border-radius:50%;background:#fff;box-shadow:0 1px 2px #24314944;transition:transform .15s}
#heatPower:checked{background:var(--teal);border-color:var(--teal)}
#heatPower:checked:before{transform:translateX(14px)}
#heatPower:focus-visible{outline:2px solid var(--navy);outline-offset:3px}

.inspector-focus{margin-top:8px;border:1px solid var(--line);border-radius:6px;background:transparent;color:var(--navy);padding:6px 9px;font:inherit;cursor:pointer}.inspector-focus:focus-visible{outline:2px solid var(--teal);outline-offset:2px}
/* Keep projected pin dots behind readable callout text in both directions. */
#tags .tag{z-index:2}

/* Technical net readouts: original, projected onto each labelled wire. */
.wire-badge{position:absolute;transform:translate(-50%,-50%);padding:3px 6px;border:1px solid var(--wire-color);border-radius:5px;background:#fff9e9;color:var(--wire-color);font:600 10px var(--mono);white-space:nowrap;pointer-events:none;z-index:3;unicode-bidi:isolate;box-shadow:0 1px 2px #18213d15}
#leaders .wire-leader{stroke-width:1;stroke-dasharray:2 2;opacity:.7}
@media(min-width:1024px){.wire-badge{font-size:11px;padding:4px 7px}}

#focusMap{position:absolute;right:14px;bottom:55px;width:144px;height:96px;background:var(--card);border:1px solid var(--line);border-radius:7px;z-index:9;box-shadow:0 2px 6px #18213d18;cursor:crosshair}
#focusMap[hidden]{display:none}
#focusMap:focus-visible{outline:3px solid var(--teal);outline-offset:3px}
@media(max-width:1023px){#focusMap{display:none}}

/* Keep the physical-wiring warning next to the simplified ultrasonic scene. */
.wiring-cue{position:absolute;inset-inline:12px;bottom:66px;margin:auto;max-width:420px;z-index:5;border:1px solid #a96832;border-radius:7px;background:#fff4df;color:#69411f;padding:7px 10px;font-family:var(--cond);font-size:12px;line-height:1.3;cursor:pointer;text-align:start;box-shadow:0 3px 10px #52331b12}
.wiring-cue[hidden]{display:none}.wiring-cue:focus-visible{outline:2px solid var(--teal);outline-offset:3px}
@media(min-width:1024px){.wiring-cue{bottom:68px;max-width:480px}}

/* Learner-paced blink: teaching controls, not another floating scene overlay. */
.blink-guide{margin:14px 0;border:1px solid var(--line,#d5d5c8);border-radius:10px;background:var(--card,#fffdf6);padding:16px;color:var(--ink,#283330)}
.guide-top{display:flex;justify-content:space-between;gap:12px;font:600 12px Barlow,sans-serif;color:var(--teal,#1a7778)}
.guide-explanation{min-height:110px}.guide-explanation h3{font:600 21px 'Barlow Semi Condensed',sans-serif;margin:12px 0 6px}.guide-explanation p{font:15px/1.5 Barlow,sans-serif;margin:0 0 14px}
.guide-controls{display:flex;gap:8px}.guide-controls button{min-height:44px;border:1px solid #becac2;border-radius:8px;padding:8px 12px;background:#fffdf6;color:#243e38;font:600 15px Barlow,sans-serif;cursor:pointer}
.guide-controls #guideNext{flex:1;background:#216e64;color:#fff;border-color:#216e64;transition:transform .2s cubic-bezier(.2,1.8,.5,1),box-shadow .2s;box-shadow:0 3px 0 #13483f}
.guide-controls #guideNext:active{transform:translateY(3px) scale(.97);box-shadow:none}.guide-controls button:disabled{opacity:.5;cursor:default}.guide-controls button:focus-visible,.guide-continuous:focus-visible{outline:3px solid #c37236;outline-offset:3px}
.guide-continuous{margin-top:12px;padding:7px 0;border:0;background:transparent;text-decoration:underline;color:#265f56;font:14px Barlow,sans-serif;min-height:44px;cursor:pointer}
@media(prefers-reduced-motion:reduce){.guide-controls #guideNext{transition:none}.guide-controls #guideNext:active{transform:none}}
html.reduce-motion .guide-controls #guideNext{transition:none}html.reduce-motion .guide-controls #guideNext:active{transform:none}

.guide-controls button[aria-disabled=true]{opacity:.5;cursor:default}

@media(max-width:1023px){
 .blink-learning .stage-wrap{height:calc(100svh - 210px);min-height:500px;max-height:710px}
 .blink-learning #stage,.blink-learning .leaders,.blink-learning .tags,.blink-learning .stage-vignette{height:calc(100% - 245px);bottom:auto}
 .blink-learning .stage-wrap .toolbar{bottom:250px}
 .blink-learning .stage-wrap .stage-credit{bottom:249px}
 .stage-wrap > .blink-guide{position:absolute;bottom:0;left:0;right:0;margin:0;border-radius:0;border-width:1px 0 0;padding:12px 14px;background:var(--card,#fffdf6);z-index:12}
 .stage-wrap > .blink-guide .guide-explanation{min-height:84px}
 .stage-wrap > .blink-guide .guide-explanation h3{font-size:19px;margin-top:8px}
 .stage-wrap > .blink-guide .guide-explanation p{font-size:14px;line-height:1.35;margin-bottom:10px}
 .stage-wrap > .blink-guide .guide-continuous{margin-top:4px;min-height:36px}
}

/* Keep learning controls in their own desktop column above the lesson rail. */
@media(min-width:1024px){
 .blink-learning .panel{min-height:0;overflow:hidden}
 .blink-learning .panel-body{flex:1;min-height:0;overflow-y:auto;overscroll-behavior:contain;padding-bottom:12px}
}

.guide-sample{display:flex;align-items:center;gap:8px;margin-top:10px;font-size:13px}.guide-sample select{min-height:36px;max-width:100%;font:inherit;background:var(--card);border:1px solid var(--line);border-radius:6px;padding:5px}
@media(max-width:1023px){
 .thermal-learning .stage-wrap{min-height:640px}
 .thermal-learning #stage,.thermal-learning .leaders,.thermal-learning .tags,.thermal-learning .stage-vignette{height:calc(100% - 365px)}
 .thermal-learning .stage-wrap .toolbar{bottom:370px}.thermal-learning .stage-wrap .stage-credit{bottom:369px}
 .thermal-learning .guide-sample{font-size:12px;gap:5px}.thermal-learning .guide-sample select{width:170px}
}
/* Focus/scroll targets must clear the fixed phone navigation. */
@media(max-width:1023px){html.thermal-learning{scroll-padding-bottom:80px}.thermal-learning .blink-guide{scroll-margin-bottom:80px}}

/* Board introduction: keep the existing six part names outside the 3D view.
   Functional tags in other lessons keep their own interaction contracts. */
#boardAnnotationDock[hidden]{display:none}
#stageWrap.board-intro #stage,#stageWrap.board-intro .tags,#stageWrap.board-intro .leaders,#stageWrap.board-intro .stage-vignette{height:calc(100% - 170px);bottom:auto}
#boardAnnotationDock{position:absolute;left:12px;right:12px;bottom:56px;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px;z-index:8;max-height:108px;overflow:auto;padding:3px}
#boardAnnotationDock .board-part-button{position:static;transform:none;min-height:44px;white-space:normal;justify-content:center;text-align:center;font-size:12px;letter-spacing:.02em;line-height:1.2;padding:6px;border-radius:8px}
#boardAnnotationDock .board-part-button::before{display:none}
#boardAnnotationDock .board-part-button:focus-visible{outline:3px solid var(--teal);outline-offset:1px}
#stageWrap.board-intro .stage-credit{top:30%;opacity:.5}
@media(max-width:1023px){#stageWrap.board-intro{height:70vh;min-height:540px;max-height:760px}}
#boardAnnotationDock .board-part-button .tag-tx i,#boardAnnotationDock .tag-ic{display:none}
#boardAnnotationDock .board-part-button{font-size:13px}

#boardAnnotationDock button[aria-pressed="true"]{border-color:var(--teal);box-shadow:inset 0 0 0 1px var(--teal)}
/* Short landscape is a separate model/control layout, not a tall phone crop. */
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){
 body:has(#stageWrap.board-intro) .topbar{min-height:54px;height:54px;padding:6px 14px;flex-wrap:nowrap}
 body:has(#stageWrap.board-intro) .topbar-right{width:auto;margin-left:auto}
 body:has(#stageWrap.board-intro) .brand-tag,body:has(#stageWrap.board-intro) .clock,body:has(#stageWrap.board-intro) .topbar-right{display:none}
 #stageWrap.board-intro{height:calc(100dvh - 132px);min-height:230px;margin-top:0}
 #stageWrap.board-intro #stage,#stageWrap.board-intro .tags,#stageWrap.board-intro .leaders,#stageWrap.board-intro .stage-vignette{width:calc(100% - 230px);height:calc(100% - 54px)}
 #boardAnnotationDock{left:auto;right:12px;top:12px;bottom:12px;width:206px;grid-template-columns:repeat(2,minmax(0,1fr));max-height:none}
 #stageWrap.board-intro .toolbar{left:10px;right:240px;bottom:8px;width:auto;transform:none;justify-content:space-around;gap:0;padding:3px}
 #stageWrap.board-intro .stage-credit,#stageWrap.board-intro .view-hint{display:none}
}
/* Localized part names must stay inside their own button, including side docks. */
#boardAnnotationDock .board-part-button .tag-tx{min-width:0;max-width:100%}
#boardAnnotationDock .board-part-button b{display:block;max-width:100%;white-space:normal;overflow-wrap:anywhere;word-break:normal}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){
 #stageWrap.board-intro #stage,#stageWrap.board-intro .tags,#stageWrap.board-intro .leaders,#stageWrap.board-intro .stage-vignette{left:0;right:auto}
}
/* Short landscape details are one opaque reading surface, never model/text stacking. */
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){
 .main:has(#sheet.open) #stageWrap.board-intro #stage,.main:has(#sheet.open) #stageWrap.board-intro .tags,.main:has(#sheet.open) #stageWrap.board-intro .leaders{visibility:hidden}
 .main:has(#sheet.open) #stageWrap.board-intro #boardAnnotationDock,.main:has(#sheet.open) #stageWrap.board-intro .toolbar{visibility:hidden;pointer-events:none}
}

#boardAnnotationDock .board-part-button b.word-parts{overflow-wrap:normal;word-break:normal}
/* Blink keeps all four labels/actions below its fitted circuit, never on parts. */
#stageWrap.blink-docked #stage,#stageWrap.blink-docked .tags,#stageWrap.blink-docked .leaders,#stageWrap.blink-docked .stage-vignette{height:calc(100% - 360px);bottom:auto}
#stageWrap.blink-docked #boardAnnotationDock{bottom:244px;max-height:108px;grid-template-columns:repeat(2,minmax(0,1fr))}
#stageWrap.blink-docked .toolbar{bottom:193px}
#stageWrap.blink-docked .stage-credit,#stageWrap.blink-docked .view-hint{display:none}
@media(max-width:1023px){#stageWrap.blink-docked{height:800px;min-height:800px;max-height:none}#stageWrap.blink-docked .blink-guide{bottom:0}}
@media(min-width:1024px){#stageWrap.blink-docked #stage,#stageWrap.blink-docked .tags,#stageWrap.blink-docked .leaders,#stageWrap.blink-docked .stage-vignette{height:calc(100% - 170px)}#stageWrap.blink-docked #boardAnnotationDock{bottom:56px}#stageWrap.blink-docked .toolbar{bottom:8px}}

#stageWrap.blink-docked > #runTag{top:auto!important;left:12px!important;bottom:354px;transform:none;font-size:12px}
@media(min-width:1024px){#stageWrap.blink-docked > #runTag{bottom:112px}}
@media(max-width:1023px) and (min-height:501px){
 #stageWrap.blink-docked{height:auto;min-height:0;max-height:none}
 #stageWrap.blink-docked #stage,#stageWrap.blink-docked .tags,#stageWrap.blink-docked .leaders,#stageWrap.blink-docked .stage-vignette{height:262px}
 #stageWrap.blink-docked #boardAnnotationDock{top:268px;bottom:auto;display:flex;gap:6px;max-height:52px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}
 #stageWrap.blink-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 10px;font-size:11.5px;letter-spacing:.02em}
 #stageWrap.blink-docked .toolbar{top:322px;bottom:auto}
 #stageWrap.blink-docked > #runTag{top:368px!important;bottom:auto}
 #stageWrap.blink-docked .blink-guide{position:relative;top:auto;bottom:auto;margin-top:368px}
}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){
 body:has(#stageWrap.blink-docked) .topbar{min-height:54px;height:54px;padding:6px 14px;flex-wrap:nowrap}
 body:has(#stageWrap.blink-docked) .brand-tag,body:has(#stageWrap.blink-docked) .clock,body:has(#stageWrap.blink-docked) .topbar-right{display:none}
 #stageWrap.blink-docked{height:540px;min-height:540px;margin-top:0}
 #stageWrap.blink-docked #stage,#stageWrap.blink-docked .tags,#stageWrap.blink-docked .leaders,#stageWrap.blink-docked .stage-vignette{left:0;right:auto;width:calc(100% - 230px);height:204px}
 #stageWrap.blink-docked #boardAnnotationDock{left:auto;right:12px;top:12px;bottom:auto;width:206px;max-height:200px}
 #stageWrap.blink-docked .toolbar{left:10px;right:240px;top:214px;bottom:auto;width:auto;transform:none;justify-content:space-around}
 #stageWrap.blink-docked > #runTag{top:144px!important;left:auto!important;right:12px;bottom:auto;width:206px}
 #stageWrap.blink-docked .blink-guide{top:270px;bottom:0}
 .main:has(#sheet.open) #stageWrap.blink-docked #stage,.main:has(#sheet.open) #stageWrap.blink-docked .tags,.main:has(#sheet.open) #stageWrap.blink-docked .leaders{visibility:hidden}
 .main:has(#sheet.open) #stageWrap.blink-docked #boardAnnotationDock,.main:has(#sheet.open) #stageWrap.blink-docked .toolbar{visibility:hidden;pointer-events:none}
}
@media(min-width:1024px){#stageWrap.blink-docked #stage,#stageWrap.blink-docked .tags,#stageWrap.blink-docked .leaders,#stageWrap.blink-docked .stage-vignette{height:calc(100% - 150px)}
#stageWrap.blink-docked #boardAnnotationDock{bottom:56px;max-height:52px;display:flex;gap:8px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}
#stageWrap.blink-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 14px}}
/* Input lessons retain their click/drag contracts in reserved controls. */
#stageWrap.functional-docked #stage,#stageWrap.functional-docked .tags,#stageWrap.functional-docked .leaders,#stageWrap.functional-docked .stage-vignette{height:calc(100% - 234px);bottom:auto}
#stageWrap.functional-docked #boardAnnotationDock{bottom:108px;max-height:112px;grid-template-columns:repeat(2,minmax(0,1fr))}
@media(min-width:1024px){#stageWrap.functional-docked #stage,#stageWrap.functional-docked .tags,#stageWrap.functional-docked .leaders,#stageWrap.functional-docked .stage-vignette{height:calc(100% - 148px)}
#stageWrap.functional-docked #boardAnnotationDock{bottom:96px;max-height:52px;display:flex;gap:8px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}
#stageWrap.functional-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 14px}}
#stageWrap.functional-docked .stage-credit,#stageWrap.functional-docked .view-hint{display:none}
#stageWrap.functional-docked .toolbar{bottom:8px}
#circuitReadouts{position:absolute;left:12px;right:12px;bottom:58px;display:flex;gap:6px;flex-wrap:wrap;justify-content:center;min-height:32px}
#circuitReadouts .wire-badge{position:static;transform:none;font-size:12px;min-height:28px;align-items:center}
@media(max-width:1023px){#stageWrap.functional-docked{height:590px;min-height:590px;max-height:none}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){
 body:has(#stageWrap.functional-docked) .topbar{min-height:54px;height:54px;padding:6px 14px;flex-wrap:nowrap}
 body:has(#stageWrap.functional-docked) .brand-tag,body:has(#stageWrap.functional-docked) .clock,body:has(#stageWrap.functional-docked) .topbar-right{display:none}
 #stageWrap.functional-docked{height:274px;min-height:274px;margin-top:0}
 #stageWrap.functional-docked #stage,#stageWrap.functional-docked .tags,#stageWrap.functional-docked .leaders,#stageWrap.functional-docked .stage-vignette{left:0;right:auto;width:calc(100% - 284px);height:210px}
 #stageWrap.functional-docked #boardAnnotationDock{left:auto;right:12px;top:12px;bottom:auto;width:260px;max-height:140px}
 #stageWrap.functional-docked #circuitReadouts{left:auto;right:12px;top:158px;bottom:auto;width:260px}
 #stageWrap.functional-docked .toolbar{left:10px;right:294px;bottom:8px;width:auto;transform:none;justify-content:space-around}
 .main:has(#sheet.open) #stageWrap.functional-docked #stage,.main:has(#sheet.open) #stageWrap.functional-docked .tags,.main:has(#sheet.open) #stageWrap.functional-docked .leaders{visibility:hidden}
 .main:has(#sheet.open) #stageWrap.functional-docked #boardAnnotationDock,.main:has(#sheet.open) #stageWrap.functional-docked .toolbar,.main:has(#sheet.open) #circuitReadouts{visibility:hidden;pointer-events:none}
}

/* Ultrasonic wiring warning is a separate reserved row, never a circuit overlay. */
#stageWrap.distance-docked #wiringCue{top:auto;bottom:166px;left:12px;right:12px;max-width:none;min-height:44px}
#stageWrap.distance-docked #boardAnnotationDock{bottom:58px;max-height:100px}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){
 #stageWrap.distance-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:140px}
 #stageWrap.distance-docked #wiringCue{left:auto;right:12px;top:160px;bottom:auto;width:260px;max-width:260px}
 .main:has(#sheet.open) #stageWrap.distance-docked #wiringCue{visibility:hidden;pointer-events:none}
}
/* The wiring diagram is a reading surface, not a translucent model overlay. */
#stageWrap.distance-docked .schematic{background:#f8f2e5}
#stageWrap.distance-docked:has(.schematic.is-on) #stage,
#stageWrap.distance-docked:has(.schematic.is-on) .tags,
#stageWrap.distance-docked:has(.schematic.is-on) .leaders,
#stageWrap.distance-docked:has(.schematic.is-on) #boardAnnotationDock,
#stageWrap.distance-docked:has(.schematic.is-on) .toolbar{visibility:hidden;pointer-events:none}
#stageWrap.distance-docked .sch-head{flex-shrink:0;position:sticky;top:0;z-index:2;background:#f8f2e5;align-items:center}
#stageWrap.distance-docked .sch-close{width:44px;height:44px;flex-shrink:0}
#stageWrap.distance-docked .sch-body{display:block;flex-shrink:0;min-height:auto}

/* Piano notes and descriptions each have space of their own, away from wires. */
#pianoNoteDock{position:absolute;left:12px;right:12px;bottom:58px;display:grid;grid-template-columns:repeat(8,minmax(0,1fr));gap:4px}
#pianoNoteDock button{min-width:0;min-height:44px;border:1px solid #a99b84;border-radius:8px;background:#fff8ed;color:#172344;font:600 14px monospace;touch-action:none;user-select:none}
#pianoNoteDock button[aria-pressed=true]{background:#174957;color:white;box-shadow:inset 0 3px 0 #052d37}
#pianoNoteDock button:focus-visible{outline:3px solid #138c94;outline-offset:2px}
#stageWrap.piano-docked #boardAnnotationDock{bottom:110px;max-height:112px}
@media(max-width:500px){#stageWrap.piano-docked{height:600px;min-height:600px}#stageWrap.piano-docked #stage,#stageWrap.piano-docked .tags,#stageWrap.piano-docked .leaders,#stageWrap.piano-docked .stage-vignette{height:330px}#stageWrap.piano-docked #boardAnnotationDock{top:340px;bottom:auto;max-height:112px}#pianoNoteDock{grid-template-columns:repeat(4,minmax(0,1fr))}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){#stageWrap.piano-docked{height:274px;min-height:274px}#stageWrap.piano-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:112px}#pianoNoteDock{left:auto;right:12px;top:136px;bottom:auto;width:260px;grid-template-columns:repeat(4,minmax(0,1fr))}.main:has(#sheet.open) #pianoNoteDock{visibility:hidden;pointer-events:none}}

/* Motor's learner-owned guide is a separate flow surface below circuit controls. */
@media(max-width:1023px){#stageWrap.motor-docked{height:auto;min-height:0;max-height:none}#stageWrap.motor-docked #stage,#stageWrap.motor-docked .tags,#stageWrap.motor-docked .leaders,#stageWrap.motor-docked .stage-vignette{height:262px}#stageWrap.motor-docked #boardAnnotationDock{top:268px;bottom:auto;max-height:52px}#stageWrap.motor-docked #boardAnnotationDock{display:flex;gap:6px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}#stageWrap.motor-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 10px;font-size:11.5px}#stageWrap.motor-docked .toolbar{top:322px;bottom:auto}#stageWrap.motor-docked .blink-guide{position:relative;top:auto;bottom:auto;margin-top:368px}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){#stageWrap.motor-docked #stage,#stageWrap.motor-docked .tags,#stageWrap.motor-docked .leaders,#stageWrap.motor-docked .stage-vignette{height:210px}#stageWrap.motor-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:192px}#stageWrap.motor-docked .toolbar{top:224px;bottom:auto}#stageWrap.motor-docked .blink-guide{margin-top:270px}}
/* Thermostat learner-owned guide is a separate flow surface below circuit controls. */
@media(max-width:1023px){#stageWrap.thermal-docked{height:auto;min-height:0;max-height:none}#stageWrap.thermal-docked #stage,#stageWrap.thermal-docked .tags,#stageWrap.thermal-docked .leaders,#stageWrap.thermal-docked .stage-vignette{height:262px}#stageWrap.thermal-docked #boardAnnotationDock{top:268px;bottom:auto;max-height:52px}#stageWrap.thermal-docked #boardAnnotationDock{display:flex;gap:6px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}#stageWrap.thermal-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 10px;font-size:11.5px}#stageWrap.thermal-docked .toolbar{top:322px;bottom:auto}#stageWrap.thermal-docked .blink-guide{position:relative;top:auto;bottom:auto;margin-top:368px}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){#stageWrap.thermal-docked #stage,#stageWrap.thermal-docked .tags,#stageWrap.thermal-docked .leaders,#stageWrap.thermal-docked .stage-vignette{height:210px}#stageWrap.thermal-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:192px}#stageWrap.thermal-docked .toolbar{top:224px;bottom:auto}#stageWrap.thermal-docked .blink-guide{margin-top:270px}}

/* Servo guide has its own document flow after the reserved circuit and controls. */
@media(max-width:1023px){#stageWrap.servo-docked{height:auto;min-height:0;max-height:none}#stageWrap.servo-docked #stage,#stageWrap.servo-docked .tags,#stageWrap.servo-docked .leaders,#stageWrap.servo-docked .stage-vignette{height:262px}#stageWrap.servo-docked #boardAnnotationDock{top:268px;bottom:auto;max-height:52px}#stageWrap.servo-docked #boardAnnotationDock{display:flex;gap:6px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}#stageWrap.servo-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 10px;font-size:11.5px}#stageWrap.servo-docked .toolbar{top:322px;bottom:auto}#stageWrap.servo-docked .blink-guide{position:relative;top:auto;bottom:auto;margin-top:368px}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){#stageWrap.servo-docked #stage,#stageWrap.servo-docked .tags,#stageWrap.servo-docked .leaders,#stageWrap.servo-docked .stage-vignette{height:210px}#stageWrap.servo-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:192px}#stageWrap.servo-docked .toolbar{top:224px;bottom:auto}#stageWrap.servo-docked .blink-guide{margin-top:270px}}

/* Wheel target guide remains outside the circuit/dock/toolbar at mobile widths. */
@media(max-width:1023px){#stageWrap.wheel-docked{height:auto;min-height:0;max-height:none}#stageWrap.wheel-docked #stage,#stageWrap.wheel-docked .tags,#stageWrap.wheel-docked .leaders,#stageWrap.wheel-docked .stage-vignette{height:262px}#stageWrap.wheel-docked #boardAnnotationDock{top:268px;bottom:auto;max-height:52px}#stageWrap.wheel-docked #boardAnnotationDock{display:flex;gap:6px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}#stageWrap.wheel-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 10px;font-size:11.5px}#stageWrap.wheel-docked .toolbar{top:322px;bottom:auto}#stageWrap.wheel-docked .blink-guide{position:relative;top:auto;bottom:auto;margin-top:368px}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){#stageWrap.wheel-docked #stage,#stageWrap.wheel-docked .tags,#stageWrap.wheel-docked .leaders,#stageWrap.wheel-docked .stage-vignette{height:210px}#stageWrap.wheel-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:192px}#stageWrap.wheel-docked .toolbar{top:224px;bottom:auto}#stageWrap.wheel-docked .blink-guide{margin-top:270px}}


/* Five plant controls need three full rows, separate from the guide. */
#stageWrap.plant-docked #stage,#stageWrap.plant-docked .tags,#stageWrap.plant-docked .leaders,#stageWrap.plant-docked .stage-vignette{height:calc(100% - 286px)}
#stageWrap.plant-docked #boardAnnotationDock{max-height:164px}
@media(min-width:1024px){#stageWrap.plant-docked #stage,#stageWrap.plant-docked .tags,#stageWrap.plant-docked .leaders,#stageWrap.plant-docked .stage-vignette{height:calc(100% - 148px)}
#stageWrap.plant-docked #boardAnnotationDock{max-height:52px;display:flex;gap:8px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}
#stageWrap.plant-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 14px}}
@media(max-width:1023px){#stageWrap.plant-docked{height:auto;min-height:0;max-height:none}#stageWrap.plant-docked #stage,#stageWrap.plant-docked .tags,#stageWrap.plant-docked .leaders,#stageWrap.plant-docked .stage-vignette{height:262px}#stageWrap.plant-docked #boardAnnotationDock{top:268px;bottom:auto;max-height:52px;display:flex;gap:6px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}#stageWrap.plant-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 10px;font-size:11.5px}#stageWrap.plant-docked .toolbar{top:322px;bottom:auto}#stageWrap.plant-docked .blink-guide{position:relative;top:auto;bottom:auto;margin-top:368px}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){#stageWrap.plant-docked #stage,#stageWrap.plant-docked .tags,#stageWrap.plant-docked .leaders,#stageWrap.plant-docked .stage-vignette{height:210px}#stageWrap.plant-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:192px}#stageWrap.plant-docked .toolbar{top:224px;bottom:auto}#stageWrap.plant-docked .blink-guide{margin-top:270px}}

/* Force history guide is separate from the written output, press control and circuit. */
/* Servo guide has its own document flow after the reserved circuit and controls. */
@media(max-width:1023px){#stageWrap.force-docked{height:auto;min-height:0;max-height:none}#stageWrap.force-docked #stage,#stageWrap.force-docked .tags,#stageWrap.force-docked .leaders,#stageWrap.force-docked .stage-vignette{height:262px}#stageWrap.force-docked #boardAnnotationDock{top:268px;bottom:auto;max-height:52px}#stageWrap.force-docked #boardAnnotationDock{display:flex;gap:6px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}#stageWrap.force-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 10px;font-size:11.5px}#stageWrap.force-docked .toolbar{top:322px;bottom:auto}#stageWrap.force-docked .blink-guide{position:relative;top:auto;bottom:auto;margin-top:368px}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){#stageWrap.force-docked #stage,#stageWrap.force-docked .tags,#stageWrap.force-docked .leaders,#stageWrap.force-docked .stage-vignette{height:210px}#stageWrap.force-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:192px}#stageWrap.force-docked .toolbar{top:224px;bottom:auto}#stageWrap.force-docked .blink-guide{margin-top:270px}}


/* Parking retains its ECHO voltage-divider warning in its own row. */
/* Five plant controls need three full rows, separate from the guide. */
#stageWrap.parking-docked #stage,#stageWrap.parking-docked .tags,#stageWrap.parking-docked .leaders,#stageWrap.parking-docked .stage-vignette{height:calc(100% - 286px)}
@media(min-width:1024px){#stageWrap.parking-docked #stage,#stageWrap.parking-docked .tags,#stageWrap.parking-docked .leaders,#stageWrap.parking-docked .stage-vignette{height:calc(100% - 196px)}}
#stageWrap.parking-docked #boardAnnotationDock{max-height:164px}
@media(max-width:1023px){#stageWrap.parking-docked{height:auto;min-height:0;max-height:none}#stageWrap.parking-docked #stage,#stageWrap.parking-docked .tags,#stageWrap.parking-docked .leaders,#stageWrap.parking-docked .stage-vignette{height:226px}#stageWrap.parking-docked #boardAnnotationDock{top:278px;bottom:auto;max-height:52px;display:flex;gap:6px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}#stageWrap.parking-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 10px;font-size:11.5px}#stageWrap.parking-docked .toolbar{top:332px;bottom:auto}#stageWrap.parking-docked .blink-guide{position:relative;top:auto;bottom:auto;margin-top:380px}#stageWrap.parking-docked .blink-guide .guide-explanation{min-height:84px}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){#stageWrap.parking-docked #stage,#stageWrap.parking-docked .tags,#stageWrap.parking-docked .leaders,#stageWrap.parking-docked .stage-vignette{height:210px}#stageWrap.parking-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:192px}#stageWrap.parking-docked .toolbar{top:224px;bottom:auto}#stageWrap.parking-docked .blink-guide{margin-top:270px}}


#stageWrap.parking-docked #wiringCue{top:auto;bottom:166px;left:12px;right:12px;max-width:none;min-height:44px}
#stageWrap.parking-docked #boardAnnotationDock{bottom:58px;max-height:100px}
@media(min-width:1024px){#stageWrap.parking-docked #wiringCue{bottom:144px}
#stageWrap.parking-docked #boardAnnotationDock{bottom:58px;max-height:52px;display:flex;gap:8px;overflow-x:auto;overflow-y:hidden;padding:2px 3px}
#stageWrap.parking-docked #boardAnnotationDock .board-part-button{flex:1 0 auto;min-height:44px;padding:4px 14px}}
@media(max-width:1023px){#stageWrap.parking-docked #wiringCue{top:232px;bottom:auto;min-height:40px}#stageWrap.parking-docked #boardAnnotationDock{max-height:52px}}
@media(max-width:1023px) and (max-height:500px) and (orientation:landscape){#stageWrap.parking-docked #boardAnnotationDock{top:12px;bottom:auto;max-height:112px}#stageWrap.parking-docked #wiringCue{left:auto;right:12px;top:136px;bottom:auto;width:260px;max-width:260px}.main:has(#sheet.open) #stageWrap.parking-docked #wiringCue{visibility:hidden;pointer-events:none}}

/* The wiring diagram is a reading surface, not a translucent model overlay. */
#stageWrap.parking-docked .schematic{background:#f8f2e5}
#stageWrap.parking-docked:has(.schematic.is-on) #stage,
#stageWrap.parking-docked:has(.schematic.is-on) .tags,
#stageWrap.parking-docked:has(.schematic.is-on) .leaders,
#stageWrap.parking-docked:has(.schematic.is-on) #boardAnnotationDock,
#stageWrap.parking-docked:has(.schematic.is-on) .toolbar{visibility:hidden;pointer-events:none}
#stageWrap.parking-docked .sch-head{flex-shrink:0;position:sticky;top:0;z-index:2;background:#f8f2e5;align-items:center}
#stageWrap.parking-docked .sch-close{width:44px;height:44px;flex-shrink:0}
#stageWrap.parking-docked .sch-body{display:block;flex-shrink:0;min-height:auto}

/* The active schematic scrolls inside the viewport, including short landscapes. */
#stageWrap.parking-docked .schematic{max-height:calc(100dvh - 138px)}
#stageWrap.parking-docked:has(.schematic.is-on) #boardAnnotationDock,#stageWrap.parking-docked:has(.schematic.is-on) .toolbar{display:none}

/* ---- measured contrast pass (WCAG AA 4.5:1 on the cream surfaces; audit: tests/contrast-audit.cjs) ---- */
:root{--fn:#96461a;--gutter:#6b5f50;--faint-text:#6b5f50}
.tab{color:#6b5f50}.tab.on{color:var(--navy)}
.tok-fn{color:#96461a}.tok-num{color:#2f6a79}.tok-com{color:#6b5f50}
.brand-tag,.credit{color:#6b5f50}
.guide-top{color:#0f5f60}