/* Code tracks for Tulip Labs. Same palette and type as the 3D lab. */
*,*::before,*::after{box-sizing:border-box}
:root{
  --bg:#efebe2; --panel:#f6f3ec; --card:#fffdf8; --ink:#1d1b17; --muted:#6a655a; --line:#dcd5c6; --soft:#ece7dc;
  --c1:#e2532c; --c2:#3a4fa3; --c3:#18977f; --c4:#d99a12; --c5:#9aa6b6;
  --code-bg:#faf7f0; --k:#8a3ab9; --s:#18774f; --n:#b5521b; --cm:#7b8696; --f:#2b55c4; --bl:#fde7a6;
  --ok:#18977f; --bad:#d0432b;
  --f-display:"Pixelify Sans", ui-monospace, monospace;
  --f-body:"IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --f-mono:"IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --f-serif:"Instrument Serif", Georgia, "Times New Roman", serif;
  --pink:#ff6fb5;
  color-scheme:light;
}
@media (prefers-color-scheme: dark){:root:not([data-theme="light"]){
  --bg:#0c0d0b; --panel:#121410; --card:#181a16; --ink:#f0ede4; --muted:#a3a497; --line:#2b2e27; --soft:#1e211c;
  --c1:#ff7650; --c2:#8095ff; --c3:#38c6aa; --c4:#f0b93f; --c5:#58647a;
  --code-bg:#11130f; --k:#d49bff; --s:#7fd7a6; --n:#ffab73; --cm:#76839a; --f:#8fb1ff; --bl:#5b4a12;
  --ok:#38c6aa; --bad:#ff7a63; color-scheme:dark}}
:root[data-theme="dark"]{
  --bg:#0c0d0b; --panel:#121410; --card:#181a16; --ink:#f0ede4; --muted:#a3a497; --line:#2b2e27; --soft:#1e211c;
  --c1:#ff7650; --c2:#8095ff; --c3:#38c6aa; --c4:#f0b93f; --c5:#58647a;
  --code-bg:#11130f; --k:#d49bff; --s:#7fd7a6; --n:#ffab73; --cm:#76839a; --f:#8fb1ff; --bl:#5b4a12;
  --ok:#38c6aa; --bad:#ff7a63; color-scheme:dark}
html,body{margin:0;min-height:100%}
body{background:var(--bg);color:var(--ink);font:15px/1.6 var(--f-body);-webkit-font-smoothing:antialiased}
/* paper grain over everything, very faint */
body::before{content:"";position:fixed;inset:0;pointer-events:none;z-index:60;opacity:.05;
  background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E")}
[hidden]{display:none!important}
a{color:var(--c2)}
button{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--c2);outline-offset:2px}
code{font-family:var(--f-mono);font-size:.88em;background:var(--soft);padding:1px 5px;border-radius:4px}

/* top bar */
.top{position:sticky;top:0;z-index:20;display:flex;align-items:center;gap:12px 18px;flex-wrap:wrap;padding:10px 16px;background:var(--panel);border-bottom:1px solid var(--line)}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:inherit;min-width:0}
.logo{width:26px;height:26px;flex:none;display:grid;grid-template-columns:repeat(3,1fr);gap:2px}
.logo i{background:var(--c2);border-radius:1px}.logo i:nth-child(2),.logo i:nth-child(6){background:var(--c1)}.logo i:nth-child(4){background:var(--c3)}.logo i:nth-child(8){background:var(--c4)}
.brand b{font:700 19px/1 var(--f-display)}
.brand small{display:block;color:var(--muted);font-size:12px;margin-top:2px}
.tracks{display:flex;gap:3px;flex-wrap:wrap}
.tracks a{font-size:13px;font-weight:500;color:var(--muted);text-decoration:none;padding:6px 10px;border-radius:6px;border:1px solid transparent}
.tracks a[aria-current="page"]{color:var(--ink);background:var(--card);border-color:var(--line)}
.top .grow{flex:1}
.hdr-right{display:flex;align-items:center;gap:12px 18px;margin-left:auto}
@media (max-width:900px){.tracks{flex-wrap:nowrap;overflow-x:auto;max-width:100%;scrollbar-width:none}.tracks::-webkit-scrollbar{display:none}.tracks a{white-space:nowrap}}
.chip{font:500 12px var(--f-mono);color:var(--muted);display:flex;align-items:center;gap:6px;white-space:nowrap}
#py-chip{cursor:help;padding:6px 2px}#py-chip>span{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}
.chip i{width:8px;height:8px;border-radius:50%;background:var(--c5)}
.chip.ready i{background:var(--ok)}.chip.busy i{background:var(--c4);animation:pulse 1s infinite}
@keyframes pulse{50%{opacity:.3}}
.rv-btn{text-decoration:none;color:var(--ink);font-size:13px;font-weight:600;background:var(--card);border:1px solid var(--line);border-radius:6px;padding:6px 10px;cursor:pointer}
.rv-btn b{background:var(--c1);color:#fff;border-radius:9px;padding:0 6px;margin-left:4px;font-size:11px}
.rv-btn b.zero{background:var(--c5)}

/* layout */
.wrap{display:grid;grid-template-columns:260px minmax(0,1fr);max-width:1480px;margin:0 auto}
.side{position:sticky;top:var(--top-h,53px);align-self:start;height:calc(100vh - var(--top-h,53px));overflow:auto;padding:18px 12px 30px;border-right:1px solid var(--line);scrollbar-width:none;-ms-overflow-style:none;overscroll-behavior:contain}
.side::-webkit-scrollbar{display:none;width:0;height:0}
.side h2{display:flex;align-items:center;gap:8px;font:600 11px var(--f-mono);letter-spacing:.1em;text-transform:uppercase;color:var(--muted);margin:4px 8px 10px}
.side a{display:flex;align-items:center;gap:9px;padding:5px 8px;border-radius:6px;text-decoration:none;color:var(--ink);font-size:13.5px;line-height:1.3;position:relative}
.side a:hover{background:var(--soft)}
.side a[aria-current="page"]{background:color-mix(in srgb,var(--kc,var(--c2)) 13%,var(--card));box-shadow:inset 3px 0 0 var(--kc,var(--c2))}
.side a .n{font:700 11.5px var(--f-display);width:22px;height:22px;flex:none;display:grid;place-items:center;border-radius:4px;background:var(--soft);border:1px solid var(--line)}
.side a.top-link .n{color:var(--kc,var(--c2))}
.side a.done .n{background:color-mix(in srgb,var(--pink) 18%,var(--card));border-color:color-mix(in srgb,var(--pink) 45%,var(--line))}
.side a[aria-current="page"] .n{background:var(--kc,var(--c2));border-color:transparent;color:#fff}
.side a .t{flex:1;min-width:0}
.side .part{font:600 10.5px var(--f-mono);letter-spacing:.06em;text-transform:uppercase;color:var(--muted);margin:16px 8px 2px}
/* the chapter list hangs off each part like a file tree: a line down, a tick across */
.side .branch{margin-left:14px;border-left:1px dashed var(--line);padding-left:0}
.side .branch a{margin-left:10px}
.side .branch a::before{content:"";position:absolute;left:-10px;top:50%;width:9px;border-top:1px dashed var(--line)}
/* chapter state, in the same glyphs as the globe on the home page */
.g{width:12px;height:12px;flex:none;display:inline-grid;place-items:center;font-style:normal}
.g0::before{content:"";width:9px;height:9px;border-radius:50%;border:1.5px solid color-mix(in srgb,var(--muted) 60%,transparent)}
.g1::before{content:"✚";font-size:11px;line-height:1;color:var(--c4)}
.g2{border-radius:50%;background:var(--pink);color:#fff}
.g2::before{content:"×";font:700 11px/1 var(--f-body)}
main{min-width:0;padding:26px 32px 120px}
.col{max-width:780px;margin:0 auto}

/* home */
.hero h1{font:700 34px/1.1 var(--f-display);margin:0 0 10px}
.hero p.lede{font-size:17px;color:var(--muted);margin:0 0 22px;max-width:640px}
.ladder{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:10px;margin:18px 0 28px;padding:0;list-style:none;counter-reset:l}
.ladder li{background:var(--card);border:1px solid var(--line);border-radius:8px;padding:12px 14px;font-size:13.5px;counter-increment:l}
.ladder li b{display:block;font-size:14px;margin-bottom:2px}
.ladder li b::before{content:counter(l) " ";font-family:var(--f-display);color:var(--c2)}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:12px}
.card{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:14px 16px;text-decoration:none;color:inherit;display:block}
.card:hover{border-color:var(--c2)}
.card .num{font:700 13px var(--f-display);color:var(--c2)}
.card h3{margin:2px 0 4px;font-size:16px}
.card p{margin:0;color:var(--muted);font-size:13px}
.card .pbar{height:4px;background:var(--line);border-radius:2px;margin-top:10px;overflow:hidden}.card .pbar i{display:block;height:100%;background:var(--c3)}

/* chapter */
.ch-head .eyebrow{font:700 13px var(--f-display);color:var(--c2);letter-spacing:.04em}
.ch-head h1{font:700 30px/1.15 var(--f-display);margin:4px 0 6px}
.ch-head .tag{color:var(--muted);font-size:16px;margin:0 0 14px}
.meta{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:14px}
.pill{font-size:12.5px;border:1px solid var(--line);background:var(--card);border-radius:20px;padding:3px 10px;color:var(--muted);text-decoration:none}
a.pill{color:var(--c2);font-weight:600}
.goals{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:12px 16px 12px 16px;margin-bottom:12px}
.goals b{font-size:12px;letter-spacing:.06em;text-transform:uppercase;color:var(--muted)}
.goals ul{margin:6px 0 0;padding-left:20px}
.toc{display:flex;flex-wrap:wrap;gap:6px;margin:0 0 26px}
.toc a{font-size:12.5px;text-decoration:none;padding:3px 9px;border-radius:5px;background:var(--soft);color:var(--ink)}
.toc a.done{background:color-mix(in srgb,var(--ok) 18%,var(--soft))}
section.sec{margin:0 0 40px;scroll-margin-top:70px}
section.sec>h2{font:600 22px/1.25 var(--f-body);margin:0 0 12px;padding-top:6px;border-top:2px solid var(--line)}
.prose h3{font-size:17px;margin:18px 0 6px}.prose h4{font-size:15px;margin:14px 0 4px}
.prose p{margin:0 0 12px}.prose ul,.prose ol{margin:0 0 12px;padding-left:22px}
.note{background:color-mix(in srgb,var(--c4) 12%,var(--card));border-left:3px solid var(--c4);padding:9px 13px;border-radius:0 6px 6px 0;margin:0 0 12px;font-size:14px}
.tw{overflow-x:auto;margin:0 0 14px}
table{border-collapse:collapse;font-size:13.5px;width:100%}
th,td{border:1px solid var(--line);padding:6px 9px;text-align:left;vertical-align:top}
th{background:var(--soft)}

/* blocks */
.blk{background:var(--card);border:1px solid var(--line);border-radius:10px;margin:0 0 18px;overflow:hidden}
.blk.done{border-color:color-mix(in srgb,var(--ok) 60%,var(--line))}
.bh{display:flex;align-items:center;gap:8px;padding:9px 14px;border-bottom:1px solid var(--line);background:var(--panel);flex-wrap:wrap}
.badge{font:700 11px var(--f-body);letter-spacing:.06em;text-transform:uppercase;border-radius:4px;padding:2px 7px;color:#fff;background:var(--c5)}
.badge.run{background:var(--c2)}.badge.predict{background:var(--c4);color:#1a1a1a}.badge.parsons{background:#7a55c8}
.badge.fill{background:var(--c3)}.badge.bug{background:var(--c1)}.badge.write{background:#1d6fa5}.badge.rebuild{background:#111a2c}
.badge.quiz{background:#5d6b80}.badge.recall{background:#a04a8c}.badge.viz{background:#0f8a9c}.badge.project{background:linear-gradient(90deg,var(--c1),var(--c4));color:#fff}
.bh .t{font-weight:600;font-size:14.5px}
.bh .tick{margin-left:auto;color:var(--ok);font-weight:700;font-size:13px}
.bb{padding:12px 14px}
.bb .prompt p:last-child{margin-bottom:8px}
.bb>.prompt{font-size:14.5px}
.btns{display:flex;flex-wrap:wrap;gap:8px;margin-top:10px;align-items:center}
.btn{text-decoration:none;color:var(--ink);border:1px solid var(--line);background:var(--card);border-radius:6px;padding:6px 12px;font-size:13.5px;font-weight:500;cursor:pointer}
.btn:hover{border-color:var(--c2)}
.btn.primary{background:var(--c2);border-color:var(--c2);color:#fff}
.btn[disabled]{opacity:.5;cursor:default}
.kbd{font:11px var(--f-mono);color:var(--muted)}

/* editor */
.ed{position:relative;font:13.5px/1.55 var(--f-mono);background:var(--code-bg);border:1px solid var(--line);border-radius:7px;overflow:hidden}
.ed pre,.ed textarea{margin:0;padding:10px 12px 10px 46px;font:inherit;white-space:pre;tab-size:4;border:0;min-height:44px;overflow:hidden}
.ed pre{pointer-events:none;color:var(--ink)}
.ed textarea{position:absolute;inset:0;width:100%;height:100%;resize:none;background:transparent;color:transparent;caret-color:var(--ink);outline:none;overflow-x:auto;overflow-y:hidden}
.ed textarea::selection{background:color-mix(in srgb,var(--c2) 30%,transparent);color:transparent}
.ed .gut{position:absolute;left:0;top:0;bottom:0;width:36px;padding:10px 6px 0 0;text-align:right;color:var(--cm);font:inherit;border-right:1px solid var(--line);background:var(--panel);pointer-events:none;white-space:pre}
.ed.ro textarea{caret-color:transparent}
.ed:focus-within{border-color:var(--c2)}
.tk-k{color:var(--k);font-weight:600}.tk-s{color:var(--s)}.tk-n{color:var(--n)}.tk-c{color:var(--cm);font-style:italic}.tk-f{color:var(--f)}.tk-b{color:var(--f)}
.tk-blank{background:var(--bl);border-radius:3px;outline:1px dashed var(--c4)}

/* output */
.out{margin-top:10px;font:12.5px/1.5 var(--f-mono);white-space:pre-wrap;word-break:break-word;background:var(--soft);border-radius:7px;padding:9px 12px;max-height:360px;overflow:auto}
.out.err{background:color-mix(in srgb,var(--bad) 10%,var(--card));color:var(--bad)}
.out:empty{display:none}
.figs img{display:block;max-width:100%;margin-top:10px;border-radius:6px;background:#fff;border:1px solid var(--line)}
.result{margin-top:10px;border-radius:7px;padding:10px 12px;font-size:14px}
.result.pass{background:color-mix(in srgb,var(--ok) 14%,var(--card));border:1px solid color-mix(in srgb,var(--ok) 50%,transparent)}
.result.fail{background:color-mix(in srgb,var(--bad) 9%,var(--card));border:1px solid color-mix(in srgb,var(--bad) 40%,transparent)}
.result pre{font:12.5px/1.5 var(--f-mono);margin:6px 0 0;white-space:pre-wrap}
.meter{display:inline-flex;gap:3px;vertical-align:middle;margin-left:6px}.meter i{width:10px;height:10px;border-radius:2px;background:var(--line)}.meter i.on{background:var(--ok)}
.hint{margin-top:10px;background:color-mix(in srgb,var(--c2) 8%,var(--card));border-left:3px solid var(--c2);padding:8px 12px;border-radius:0 6px 6px 0;font-size:14px}
.hint p{margin:0}
.sol{margin-top:10px}
.sol>b{font-size:12px;color:var(--muted);text-transform:uppercase;letter-spacing:.06em}

/* animations, rewards, celebration */
.player{margin-top:10px;max-width:560px}
.flip{display:block;width:100%;image-rendering:pixelated;border-radius:6px;border:1px solid var(--line);background:#fff}
.pctl{display:flex;align-items:center;gap:8px;margin-top:6px}
.pctl input[type=range]{flex:1;accent-color:var(--c2)}
.btn.small{padding:3px 9px;font-size:12.5px;white-space:nowrap}
.reward{margin-top:12px;border-radius:10px;padding:12px 14px;background:linear-gradient(135deg,color-mix(in srgb,var(--c2) 10%,var(--card)),color-mix(in srgb,var(--c3) 10%,var(--card)));border:1px solid color-mix(in srgb,var(--c2) 35%,var(--line))}
.rw-h{font:700 13px var(--f-display);letter-spacing:.05em;color:var(--c2)}
.result.pass{position:relative}
.burst{position:absolute;left:40px;top:50%;pointer-events:none}
.burst i{position:absolute;width:8px;height:8px;border-radius:1px;animation:burst .9s ease-out forwards}
@keyframes burst{from{transform:translate(0,0) scale(1);opacity:1}to{transform:translate(var(--dx),var(--dy)) scale(.4) rotate(160deg);opacity:0}}

/* predict */
.guess{width:100%;min-height:58px;font:13px/1.5 var(--f-mono);border:1px dashed var(--c4);border-radius:7px;background:var(--card);color:var(--ink);padding:8px 10px;margin-top:10px;resize:vertical}
.cmp{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:10px}
.cmp>div>b{font-size:12px;color:var(--muted)}
.cmp .out{margin-top:4px}

/* parsons */
.pz{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.pz h4{margin:0 0 6px;font-size:12px;color:var(--muted);text-transform:uppercase;letter-spacing:.06em}
.pz ol{list-style:none;margin:0;padding:6px;min-height:80px;border:1px dashed var(--line);border-radius:7px;background:var(--code-bg)}
.pz li{display:flex;align-items:center;gap:6px;margin:3px 0}
.pz li button.ln{flex:1;text-align:left;font:12.5px/1.45 var(--f-mono);white-space:pre;overflow-x:auto;background:var(--card);border:1px solid var(--line);border-radius:5px;padding:4px 8px;cursor:pointer}
.pz li button.ln:hover{border-color:var(--c2)}
.pz li.wrong button.ln{border-color:var(--bad);background:color-mix(in srgb,var(--bad) 8%,var(--card))}
.pz li.right button.ln{border-color:var(--ok)}
.pz .mv{border:1px solid var(--line);background:var(--card);border-radius:4px;width:24px;height:24px;cursor:pointer;font-size:11px;padding:0}

/* step-by-step */
.stephead{position:sticky;top:var(--top-h,53px);z-index:10;background:color-mix(in srgb,var(--bg) 92%,transparent);backdrop-filter:blur(6px);padding:10px 0 12px;margin:0 0 18px;border-bottom:1px solid var(--line)}
.steplabel{font-size:13.5px;color:var(--muted);margin-bottom:7px}.steplabel b{color:var(--ink)}
.dots{display:flex;gap:5px;margin-bottom:8px;flex-wrap:wrap}
.dot{width:22px;height:10px;border-radius:3px;border:0;padding:0;background:var(--line);cursor:pointer}
.dot.done{background:var(--ok)}.dot.now{background:var(--c2)}.dot.locked{cursor:default;opacity:.6}
.stepbar{height:4px;background:var(--line);border-radius:2px;overflow:hidden}.stepfill{height:100%;background:var(--c3);transition:width .4s}
.stepno{display:block;font:700 12px var(--f-display);color:var(--c2);letter-spacing:.05em;margin-bottom:2px}
.gate{border:2px dashed var(--line);border-radius:12px;padding:16px 18px;margin:8px 0 30px;text-align:center}
.gate p{margin:0 0 4px;color:var(--muted)}
.gate.open{border-style:solid;border-color:var(--ok);background:color-mix(in srgb,var(--ok) 8%,var(--card))}
.gate.open p{color:var(--ink);font-weight:600}
.gate .btns{justify-content:center}
.btn.big{padding:10px 18px;font-size:15px}
.linkish{background:none;border:0;color:var(--muted);text-decoration:underline;cursor:pointer;font-size:13px}
.finale{background:var(--card);border:2px solid var(--ok);border-radius:14px;padding:22px 24px;margin:10px 0 30px}
.finale .eyebrow{font:700 13px var(--f-display);color:var(--ok);letter-spacing:.05em}
.finale h2{margin:4px 0 8px;font-size:22px}
.wins{list-style:none;padding:0;margin:0 0 12px}.wins li{padding:4px 0 4px 26px;position:relative}
.wins li::before{content:"✓";position:absolute;left:4px;color:var(--ok);font-weight:700}
.stats{font-size:12.5px;color:var(--muted);white-space:nowrap}.stats b{color:var(--ink)}

/* quiz + recall */
.opts{display:grid;gap:7px}
.opt{text-align:left;border:1px solid var(--line);background:var(--card);border-radius:7px;padding:8px 12px;cursor:pointer;font-size:14px}
.opt:hover{border-color:var(--c2)}
.opt.right{border-color:var(--ok);background:color-mix(in srgb,var(--ok) 12%,var(--card))}
.opt.wrong{border-color:var(--bad);background:color-mix(in srgb,var(--bad) 9%,var(--card))}
.why{margin-top:10px;font-size:14px}.why p{margin:0 0 6px}
.ans{margin-top:10px;background:var(--soft);border-radius:7px;padding:10px 12px;font-size:14px}.ans p{margin:0 0 6px}
.rate{display:flex;gap:8px;margin-top:10px;flex-wrap:wrap;align-items:center;font-size:13px;color:var(--muted)}

.bridge{display:flex;gap:14px;align-items:center;background:color-mix(in srgb,var(--c2) 9%,var(--card));border:1px solid color-mix(in srgb,var(--c2) 35%,var(--line));border-radius:10px;padding:12px 16px;margin:0 0 18px}
.bridge .cube{width:34px;height:34px;flex:none;display:grid;grid-template-columns:1fr 1fr;gap:3px}
.bridge .cube i{background:var(--c2);border-radius:2px}.bridge .cube i:nth-child(2){background:var(--c1)}.bridge .cube i:nth-child(3){background:var(--c3)}
.bridge p{margin:0;font-size:14px}

.pager{display:flex;justify-content:space-between;gap:10px;margin-top:30px}
.toast{pointer-events:none;position:fixed;top:64px;right:16px;background:var(--ink);color:var(--bg);padding:8px 16px;border-radius:8px;font-size:14px;z-index:50}
.empty{color:var(--muted);text-align:center;padding:40px 10px}
.menu-btn{display:none}

@media (max-width: 860px){
  .wrap{grid-template-columns:1fr}
  .side{position:fixed;inset:var(--top-h,53px) 0 0 0;height:auto;background:var(--panel);z-index:15;border-right:0;display:none}
  body.menu .side{display:block}
  .menu-btn{display:inline-block}
  .top{position:static}
  .stephead{top:0}
  .side{inset:0;padding-top:60px}
  body.menu .menu-btn{position:fixed;top:12px;left:12px;z-index:30}
  main{padding:18px 16px 100px}
  .pz,.cmp{grid-template-columns:1fr}
  .tracks a{padding:5px 7px}
}
@media (prefers-reduced-motion: reduce){*{animation:none!important;scroll-behavior:auto!important}}

/* simulations */
.vizblk .bb{padding:0}
.vizblk .bb>.prompt{padding:12px 14px 0}
.vgoal{margin:10px 14px 0;font-size:14px;background:color-mix(in srgb,var(--c4) 14%,var(--card));border:1px solid color-mix(in srgb,var(--c4) 45%,var(--line));border-radius:7px;padding:7px 11px}
.vizblk.done .vgoal{background:color-mix(in srgb,var(--ok) 12%,var(--card));border-color:color-mix(in srgb,var(--ok) 45%,var(--line))}
.vstage{padding:12px 14px 14px}
.vfail{padding:18px;border:1px dashed var(--line,#ccc);border-radius:10px;text-align:center}.vfail p{margin:0 0 10px}
.vz{display:grid;grid-template-columns:minmax(0,1fr) 270px;gap:12px}
.vz-view{position:relative;min-height:320px;border:1px solid var(--line);border-radius:8px;overflow:hidden;touch-action:none;cursor:grab;
  /* a soft studio backdrop: light from above, a faint dot grid like graph paper, a warm floor glow */
  background:radial-gradient(120% 80% at 50% -10%,color-mix(in srgb,var(--c2) 9%,transparent),transparent 62%),
    radial-gradient(90% 50% at 50% 110%,color-mix(in srgb,var(--c4) 8%,transparent),transparent 70%),
    radial-gradient(circle at 1px 1px,color-mix(in srgb,var(--ink) 10%,transparent) 1px,transparent 1.5px) 0 0/18px 18px,
    var(--code-bg)}
.vz-view::after{content:"";position:absolute;bottom:10px;left:10px;width:15px;height:15px;pointer-events:none;opacity:.75;
  background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 3 3'%3E%3Cpath fill='%23ff6fb5' d='M0 0h1v1H0zM1 1h2v1H1zM2 2h1v1H2z'/%3E%3C/svg%3E") 0 0/100% 100%}
.vz-view:active{cursor:grabbing}
.vz-view canvas{display:block;width:100%;height:100%}
.vz-hud{position:absolute;left:8px;top:8px;right:8px;pointer-events:none;font:12px/1.45 var(--f-mono);color:var(--ink);text-shadow:0 1px 0 var(--card)}
.vz-tip{position:absolute;right:8px;bottom:6px;font:11px var(--f-mono);color:var(--muted);pointer-events:none}
.vz-side{display:flex;flex-direction:column;gap:10px;min-width:0}
.vz-ctl{display:flex;flex-direction:column;gap:8px}
.vz-ctl .row{display:flex;flex-wrap:wrap;gap:6px;align-items:center}
.vz-ctl label{font-size:12.5px;color:var(--muted);display:flex;flex-direction:column;gap:3px}
.vz-ctl input[type=range]{accent-color:var(--c2);width:100%}
.vz-ctl input[type=text]{font:13px var(--f-mono);border:1px solid var(--line);border-radius:6px;padding:6px 8px;background:var(--card);color:var(--ink);width:100%}
.vz-seg{display:inline-flex;flex-wrap:wrap;max-width:100%;border:1px solid var(--line);border-radius:6px;overflow:hidden}
.vz-seg button{border:0;background:var(--card);padding:5px 10px;font-size:12.5px;cursor:pointer}
.vz-seg button+button{border-left:1px solid var(--line)}
.vz-seg button.on{background:var(--c2);color:#fff}
.vz-explain{background:var(--panel);border:1px solid var(--line);border-left:4px solid var(--c3);border-radius:8px;padding:9px 12px;font-size:13.5px}
.vz-explain h5{margin:0 0 4px;font-size:13.5px}
.vz-explain p{margin:0 0 6px}.vz-explain p:last-child{margin:0}
.vz-status{font:12.5px/1.5 var(--f-mono);background:var(--soft);border-radius:7px;padding:8px 10px;white-space:pre-wrap;word-break:break-word}
.vz-status:empty{display:none}
.vz-2d{width:100%;display:block;border:1px solid var(--line);border-radius:8px;background:var(--card)}
.vz.wide{grid-template-columns:minmax(0,1fr)}
.vz.wide .vz-side{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:10px 14px;align-items:start}
.vz.wide .vz-ctl{grid-row:span 2}
@media (max-width: 860px){.vz{grid-template-columns:1fr}.vz.wide .vz-side{grid-template-columns:minmax(0,1fr)}}

/* real-world projects */
.projblk{border-width:2px;border-color:color-mix(in srgb,var(--c4) 55%,var(--line))}
.projblk .bh{background:linear-gradient(90deg,color-mix(in srgb,var(--c1) 10%,var(--panel)),color-mix(in srgb,var(--c4) 12%,var(--panel)))}
.client{font-size:13.5px;color:var(--muted);margin-bottom:6px}
.pwhy{background:var(--soft);border-radius:8px;padding:9px 12px;margin:10px 0;font-size:14px}
.pwhy>b{display:block;font-size:12px;text-transform:uppercase;letter-spacing:.06em;color:var(--muted);margin-bottom:3px}
.pwhy p{margin:0 0 6px}.pwhy p:last-child{margin:0}
.skills{display:flex;flex-wrap:wrap;gap:6px;margin:8px 0}
.mh{margin:14px 0 6px;font-size:12px;text-transform:uppercase;letter-spacing:.06em;color:var(--muted)}
.miles{list-style:none;padding:0;margin:0;display:grid;gap:6px;counter-reset:m}
.miles li{display:flex;gap:10px;align-items:flex-start;border:1px solid var(--line);border-radius:7px;padding:8px 10px;background:var(--card)}
.miles input{margin-top:4px;accent-color:var(--ok);width:16px;height:16px;flex:none}
.miles label{cursor:pointer;font-size:14px}
.miles li:has(input:checked){border-color:color-mix(in srgb,var(--ok) 50%,var(--line));background:color-mix(in srgb,var(--ok) 7%,var(--card))}
.pbar.big{height:6px;border-radius:3px;background:var(--line);overflow:hidden;margin-top:8px}.pbar.big i{display:block;height:100%;width:0;background:var(--c4);transition:width .3s}
.stretch{margin-top:12px;font-size:14px}.stretch summary{cursor:pointer;font-weight:600}
/* Run button while Python downloads or code runs */
.btn.loading{display:inline-flex;align-items:center;gap:8px;cursor:progress}
.btn.loading::before{content:"";width:13px;height:13px;border-radius:50%;border:2px solid currentColor;border-right-color:transparent;animation:spin .8s linear infinite;flex:none}
.load-note{font:500 12px var(--f-mono);color:var(--muted);margin:8px 2px 0}
@keyframes spin{to{transform:rotate(360deg)}}
@media (prefers-reduced-motion:reduce){.btn.loading::before{animation-duration:2.4s}}

/* ================================================================
   The garden. Every chapter grows a pixel flower (learn/garden.js).
   Track home: a poster, keycaps for the ladder, beds of flowers.
   Chapter: a stepped cover with its flower, and a rail of steps.
   ================================================================ */
.dark{--ink:#f2efe6;--muted:#b2b2a6;--line:#30332b;color:var(--ink)}
.col.wide{max-width:1040px}

/* a stepped mark, like the pink pixel marks on the posters */
.step-mark{display:inline-block;width:12px;height:12px;flex:none;
  background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 3 3'%3E%3Cpath fill='%23ff6fb5' d='M0 0h1v1H0zM1 1h2v1H1zM2 2h1v1H2z'/%3E%3C/svg%3E") 0 0/100% 100%}

/* ---- poster */
.poster{position:relative;overflow:hidden;border-radius:6px;margin:0 0 34px;min-height:440px;padding:64px 40% 64px 36px;
  background:radial-gradient(70% 60% at 82% 100%,color-mix(in srgb,var(--kc,#ff6fb5) 26%,transparent),transparent 70%),#0e0f0c;isolation:isolate}
.poster::after{content:"";position:absolute;inset:0;pointer-events:none;opacity:.12;mix-blend-mode:screen;z-index:3;
  background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='200'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.75' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 .9 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E")}
.p-corner{position:absolute;font:500 11.5px/1.45 var(--f-mono);color:var(--muted);z-index:2;letter-spacing:.02em}
.p-corner b{color:var(--ink);font-weight:600;font-size:15px}
.p-corner.tl{top:18px;left:22px}.p-corner.tr{top:18px;right:22px;text-align:right}
.p-corner.bl{bottom:16px;left:22px}.p-corner.br{bottom:16px;right:22px;text-align:right}
.p-body{position:relative;z-index:2}
.hero .poster h1{font:400 clamp(38px,5.4vw,66px)/.98 var(--f-serif);letter-spacing:-.01em;margin:0 0 14px;color:#fff}
.p-code{font:500 13px var(--f-mono);color:#ffd21f;margin:0 0 18px}.p-code i{font-style:normal;color:var(--pink)}
.hero .poster p.lede{font-size:15.5px;color:#cfcdc2;max-width:520px;margin:0 0 22px}
.p-cta{display:flex;flex-wrap:wrap;gap:10px}
.p-art{position:absolute;right:3%;bottom:38px;width:34%;height:76%;z-index:1}
.p-art canvas{position:absolute;inset:0;width:100%;height:100%}
.p-ghost{opacity:.2}
.p-glow{position:absolute;left:12%;right:12%;bottom:6%;height:30%;
  background:radial-gradient(closest-side,color-mix(in srgb,var(--pink) 32%,transparent),transparent);filter:blur(10px)}

/* keycaps: buttons and the ladder */
.key{display:inline-flex;align-items:center;gap:8px;text-decoration:none;font:600 14px var(--f-body);color:var(--ink);
  background:var(--card);border:1px solid var(--line);border-radius:8px;padding:10px 16px;
  box-shadow:0 3px 0 color-mix(in srgb,var(--ink) 22%,transparent);transition:transform .08s,box-shadow .08s}
.key:hover{transform:translateY(-1px);box-shadow:0 4px 0 color-mix(in srgb,var(--ink) 22%,transparent)}
.key:active{transform:translateY(3px);box-shadow:0 0 0 transparent}
.poster .key{background:#1b1d18;border-color:#34372f;color:#f2efe6;box-shadow:0 3px 0 #000}
.poster .key.primary,.key.primary{background:var(--pink);border-color:var(--pink);color:#2a0b1b;box-shadow:0 3px 0 #a3336c}

.sec-h{display:flex;align-items:baseline;flex-wrap:wrap;gap:4px 10px;font:400 30px/1.1 var(--f-serif);margin:40px 0 14px}
.sec-h small{font:500 12px var(--f-mono);color:var(--muted);flex-basis:100%;margin-left:42px}
.tree{font:500 15px var(--f-mono);color:var(--kc,var(--c2));letter-spacing:-.05em;flex:none}
.hero .ladder{grid-template-columns:repeat(auto-fit,minmax(132px,1fr));gap:10px;margin:8px 0 22px}
.hero .ladder li{position:relative;background:var(--card);border:1px solid var(--line);border-radius:10px;padding:34px 12px 12px;font-size:12.5px;color:var(--muted);line-height:1.45;
  box-shadow:0 4px 0 color-mix(in srgb,var(--ink) 12%,transparent)}
.hero .ladder li b{color:var(--ink);font-size:13.5px}
.hero .ladder li b::before{content:counter(l);position:absolute;top:10px;left:12px;font:700 15px var(--f-display);color:var(--kc,var(--c2))}
.hero .ladder li::after{content:"";position:absolute;top:12px;right:12px;width:6px;height:6px;border-radius:1px;background:var(--line)}
/* on wide screens the ladder is a staircase: each rung a step higher and a shade deeper in the track colour */
@media (min-width:1100px){
  .hero .ladder{grid-template-columns:repeat(7,minmax(0,1fr));align-items:end;gap:8px}
  .hero .ladder li{min-height:calc(150px + var(--n) * 16px);background:color-mix(in srgb,var(--kc,var(--c2)) calc(var(--n) * 2.4%),var(--card))}
  .hero .ladder li::after{width:calc(6px + var(--n) * 2px);background:color-mix(in srgb,var(--kc,var(--c2)) calc(15% + var(--n) * 12%),var(--line))}
}
.hero p a,.note a{color:color-mix(in srgb,var(--kc,var(--c2)) 70%,var(--ink));text-decoration-thickness:2px;text-underline-offset:3px;font-weight:600}

/* ---- beds of flowers */
.bed{margin:0 0 26px}
.bed-h{display:flex;align-items:baseline;gap:10px;font:600 14px var(--f-body);margin:0 0 10px}
.bed-h small{margin-left:auto;font:500 11.5px var(--f-mono);color:var(--muted)}
.plots{display:grid;grid-template-columns:repeat(auto-fill,minmax(176px,1fr));gap:12px}
.plot{position:relative;display:flex;flex-direction:column;text-decoration:none;color:inherit;background:var(--card);border:1px solid var(--line);border-radius:10px;overflow:hidden;transition:transform .15s,border-color .15s}
.plot:hover{transform:translateY(-2px);border-color:var(--kc,var(--c2))}
.plot .soil{height:118px;background:linear-gradient(to bottom,color-mix(in srgb,var(--kc,var(--c2)) 7%,var(--soft)),var(--soft));border-bottom:1px solid var(--line);position:relative}
.plot .soil canvas{position:absolute;inset:6px 0 4px;width:100%;height:calc(100% - 10px)}
.plot:hover .soil canvas{animation:sway 1.6s ease-in-out infinite;transform-origin:50% 100%}
@keyframes sway{50%{transform:rotate(1.6deg)}}
.plot .num{position:absolute;top:8px;left:10px;font:700 12px var(--f-display);color:transparent}
/* a big faint chapter number sits in the soil behind the flower, so an unplanted bed isn't blank */
.plot .ghost{position:absolute;right:8px;bottom:-14px;font:400 84px/1 var(--f-serif);letter-spacing:-.04em;color:color-mix(in srgb,var(--kc,var(--c2)) 16%,transparent);pointer-events:none;transition:color .2s}
.plot:hover .ghost{color:color-mix(in srgb,var(--kc,var(--c2)) 30%,transparent)}
.plot.bloomed .ghost{color:color-mix(in srgb,var(--pink) 14%,transparent)}
/* the chapter to do next: a pink ring and a tag */
.plot.next{border-color:var(--pink);box-shadow:0 0 0 3px color-mix(in srgb,var(--pink) 22%,transparent)}
.next-tag{position:absolute;top:7px;right:8px;font:600 10.5px var(--f-mono);letter-spacing:.04em;color:#2a0b1b;background:var(--pink);padding:2px 7px;border-radius:4px;box-shadow:inset 0 -2px 0 #c2357a}
.plot.bloomed .num::after{content:"×";display:inline-grid;place-items:center;width:14px;height:14px;margin-left:6px;border-radius:50%;background:var(--pink);color:#fff;font:700 10px/1 var(--f-body);vertical-align:1px}
.plot b{font-size:14px;line-height:1.3;margin:10px 12px 2px}
.plot small{color:var(--muted);font-size:12px;line-height:1.4;margin:0 12px 12px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.plot .pbar{margin-top:auto;height:3px;background:var(--line)}.plot .pbar i{display:block;height:100%;background:var(--pink)}

/* ---- chapter cover: a stepped wash, deep track colour at the top, glowing pink-white at its heart */
.ch-head.cover{position:relative;display:grid;grid-template-columns:minmax(0,1fr) 170px;gap:12px;align-items:end;
  padding:30px 26px 34px;margin:0 0 16px;border-radius:6px 6px 0 0;overflow:hidden;isolation:isolate;
  background:radial-gradient(60% 75% at 80% 115%,#fff3ee 0,color-mix(in srgb,var(--pink) 75%,transparent) 22%,transparent 62%),
    linear-gradient(170deg,color-mix(in srgb,var(--kc,var(--c2)) 70%,#0b0c0a),color-mix(in srgb,var(--kc,var(--c2)) 88%,#3b7fe0));
  /* stepped lower edge, like the stepped bowls */
  clip-path:polygon(0 0,100% 0,100% calc(100% - 40px),calc(100% - 14px) calc(100% - 40px),calc(100% - 14px) calc(100% - 28px),calc(100% - 28px) calc(100% - 28px),calc(100% - 28px) calc(100% - 14px),calc(100% - 42px) calc(100% - 14px),calc(100% - 42px) 100%,42px 100%,42px calc(100% - 14px),28px calc(100% - 14px),28px calc(100% - 28px),14px calc(100% - 28px),14px calc(100% - 40px),0 calc(100% - 40px))}
.ch-head.cover::after{content:"";position:absolute;inset:0;pointer-events:none;opacity:.16;mix-blend-mode:overlay;z-index:-1;
  background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='200'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.8' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E")}
.ch-head.cover .eyebrow{font:500 12px var(--f-mono);color:rgba(255,255,255,.78);letter-spacing:.04em}
.ch-head.cover h1{font:400 clamp(32px,4.4vw,48px)/1.02 var(--f-serif);color:#fff;margin:8px 0 8px;letter-spacing:-.005em}
.ch-head.cover .tag{color:rgba(255,255,255,.86);font-size:15.5px;margin:0 0 16px}
.ch-head.cover .meta{margin:0 0 6px}
.ch-head.cover .pill{background:rgba(10,10,8,.32);border-color:rgba(255,255,255,.18);color:#fff;backdrop-filter:blur(4px)}
.ch-head.cover a.pill{background:#fff;color:#1d1b17;border-color:#fff}
.cv-art{position:relative;height:190px;align-self:end;margin-bottom:-10px}
.cv-art canvas{position:absolute;inset:0;width:100%;height:100%}
.cv-ghost{opacity:.18}
.goals{border-radius:0 0 10px 10px}
.goals li::marker{content:"✚  ";color:var(--pink);font-size:.8em}

/* ---- chapter grid with the step rail */
.chgrid{display:block}
.rail{display:none}
@media (min-width:1320px){
  .chgrid{display:grid;grid-template-columns:minmax(0,780px) 210px;gap:40px;justify-content:center}
  .chgrid .col{margin:0}
  .rail{display:block;position:sticky;top:calc(var(--top-h,53px) + 20px);align-self:start;max-height:calc(100vh - var(--top-h,53px) - 40px);overflow:auto;scrollbar-width:none}
  .chgrid .dots{display:none}
}
.rail-fl{height:130px;position:relative;background:var(--soft);border:1px solid var(--line);border-radius:10px;margin-bottom:14px}
.rail-fl canvas{position:absolute;inset:8px 0 4px;width:100%;height:calc(100% - 12px)}
.rail-h{font:600 10.5px var(--f-mono);letter-spacing:.08em;text-transform:uppercase;color:var(--muted);margin:0 0 6px}
.rail-steps{list-style:none;margin:0 0 12px;padding:0 0 0 6px;border-left:1px dashed var(--line)}
.rail-steps li{position:relative}
.rail-steps li::before{content:"";position:absolute;left:-6px;top:50%;width:8px;border-top:1px dashed var(--line)}
.rail-steps button{display:flex;gap:8px;align-items:center;width:100%;text-align:left;background:none;border:0;padding:5px 6px 5px 8px;border-radius:6px;cursor:pointer;font-size:13px;line-height:1.3;color:var(--ink)}
.rail-steps button:hover:not([disabled]){background:var(--soft)}
.rail-steps li.now button{background:color-mix(in srgb,var(--kc,var(--c2)) 13%,var(--card));font-weight:600}
.rail-steps li.locked button{color:var(--muted);cursor:default}
.rail-note{font:12px/1.5 var(--f-mono);color:var(--muted);margin:0}

/* step headings and the step dots as tiny keycaps */
.stepno{display:flex;align-items:center;gap:8px;color:var(--kc,var(--c2))}
.stepno::before{content:"";width:10px;height:10px;background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 3 3'%3E%3Cpath fill='%23ff6fb5' d='M0 0h1v1H0zM1 1h2v1H1zM2 2h1v1H2z'/%3E%3C/svg%3E") 0 0/100% 100%}
section.sec>h2{font:400 30px/1.1 var(--f-serif);border-top:1px dashed var(--line);padding-top:16px;letter-spacing:-.005em}
.dot{height:12px;border-radius:3px;box-shadow:0 2px 0 color-mix(in srgb,var(--ink) 15%,transparent)}
.dot.done{background:var(--pink)}.dot.now{background:var(--kc,var(--c2))}
.stepfill{background:linear-gradient(90deg,var(--kc,var(--c3)),var(--pink))}
.btn.primary{background:var(--ink);border-color:var(--ink);color:var(--bg)}
.btn.primary.big{background:var(--pink);border-color:var(--pink);color:#2a0b1b;box-shadow:0 3px 0 #a3336c;border-radius:8px}
.btn.primary.big[disabled]{background:var(--soft);border-color:var(--line);color:var(--muted);box-shadow:none;opacity:1}
.gate{border-radius:6px}

/* ---- finale: the flower grows from seed, on black paper */
.finale{display:grid;grid-template-columns:200px minmax(0,1fr);column-gap:24px;border-color:var(--pink)}
.finale>*:not(.fin-art){grid-column:2}
.fin-art{grid-row:1/span 9;align-self:start;position:relative;min-height:230px;border-radius:8px;background:radial-gradient(70% 50% at 50% 100%,color-mix(in srgb,var(--pink) 25%,transparent),transparent),#0e0f0c}
.fin-art canvas{position:absolute;inset:10px 0 6px;width:100%;height:calc(100% - 16px)}
.finale .eyebrow{color:var(--pink)}
.finale h2{font:400 32px/1.1 var(--f-serif)}

@media (max-width:860px){
  .poster{padding:84px 18px 250px;min-height:0}
  .p-corner.tl,.p-corner.tr{top:16px}
  .p-art{width:70%;height:230px;left:15%;right:auto}
  .p-corner.br{display:none}
  .ch-head.cover{grid-template-columns:1fr 92px;padding:24px 16px 34px}
  .cv-art{height:120px}
  .finale{grid-template-columns:1fr}
  .finale>*:not(.fin-art){grid-column:1}
  .fin-art{grid-row:auto;margin-bottom:14px;min-height:200px}
  .sec-h small{margin-left:0}
}
@media (prefers-reduced-motion:reduce){.plot:hover .soil canvas{animation:none}}

/* ---- lesson text: a highlighter under new words, square bullets, numbered keycaps, pixel-stepped notes */
.prose .term{background:linear-gradient(transparent 60%,color-mix(in srgb,var(--pink) 26%,transparent) 0);padding:0 1px;border-radius:1px}
.prose .term.flash{animation:flash 1.6s ease-out}
@keyframes flash{0%,30%{background-color:color-mix(in srgb,var(--pink) 45%,transparent);box-shadow:0 0 0 4px color-mix(in srgb,var(--pink) 30%,transparent)}100%{background-color:transparent;box-shadow:none}}
.prose ul{list-style:none;padding-left:20px}
.prose ul>li{position:relative}
.prose ul>li::before{content:"";position:absolute;left:-16px;top:.62em;width:6px;height:6px;background:var(--kc,var(--c2));box-shadow:2px 2px 0 color-mix(in srgb,var(--pink) 55%,transparent)}
.prose ol{list-style:none;counter-reset:o;padding-left:30px}
.prose ol>li{position:relative;counter-increment:o;margin-bottom:4px}
.prose ol>li::before{content:counter(o);position:absolute;left:-30px;top:.15em;min-width:20px;height:20px;padding:0 4px;display:grid;place-items:center;
  font:700 11px/1 var(--f-display);color:var(--ink);background:var(--card);border:1px solid var(--line);border-radius:4px;box-shadow:inset 0 -2px 0 var(--line)}
.prose blockquote{margin:0 0 14px;padding:4px 0 4px 18px;border-left:2px dashed color-mix(in srgb,var(--kc,var(--c2)) 60%,var(--line));font:400 21px/1.35 var(--f-serif);color:var(--ink)}
.prose blockquote p{margin:0}
.prose h3{font:400 23px/1.15 var(--f-serif);margin:22px 0 6px}
.prose h3::before{content:"└── ";font:13px var(--f-mono);color:var(--kc,var(--c2));vertical-align:3px}
.prose hr{border:0;height:10px;margin:22px 0;background:radial-gradient(circle,var(--line) 1.5px,transparent 2px) 0 50%/14px 10px repeat-x}
.note{position:relative;border-left:0;border-radius:6px;padding-left:34px;background:color-mix(in srgb,var(--c4) 12%,var(--card));box-shadow:inset 0 0 0 1px color-mix(in srgb,var(--c4) 28%,transparent)}
.note::before{content:"";position:absolute;left:12px;top:13px;width:12px;height:12px;background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 3 3'%3E%3Cpath fill='%23d99a12' d='M0 0h1v1H0zM1 1h2v1H1zM2 2h1v1H2z'/%3E%3C/svg%3E") 0 0/100% 100%}
th{font:600 11.5px var(--f-mono);letter-spacing:.04em;text-transform:uppercase;color:var(--muted)}
tbody tr:nth-child(even) td{background:color-mix(in srgb,var(--soft) 45%,transparent)}

/* ---- words you met, in the rail */
.rail-words{margin-top:18px}
.chips{display:flex;flex-wrap:wrap;gap:5px}
.word{font:500 12px var(--f-body);color:var(--ink);background:var(--card);border:1px solid var(--line);border-radius:5px;padding:3px 7px;cursor:pointer;box-shadow:inset 0 -2px 0 color-mix(in srgb,var(--pink) 35%,var(--line))}
.word:hover{border-color:var(--pink)}

/* ---- say it in your own words */
.own{margin:4px 0 0;border:1px dashed var(--line);border-radius:8px;background:color-mix(in srgb,var(--card) 60%,transparent)}
.own summary{list-style:none;display:flex;gap:8px;align-items:center;padding:9px 12px;cursor:pointer;font-size:13.5px}
.own summary::-webkit-details-marker{display:none}
.own summary code{color:var(--kc,var(--c2));font:12px var(--f-mono);background:none;padding:0}
.own summary small{margin-left:auto;font:600 11px var(--f-mono);color:var(--pink)}
.own[open]{border-style:solid;background:var(--card)}
.own textarea{display:block;width:calc(100% - 24px);margin:0 12px;font:400 19px/1.4 var(--f-serif);color:var(--ink);background:transparent;border:0;border-top:1px dashed var(--line);padding:10px 0;resize:vertical;min-height:64px}
.own textarea:focus{outline:none}
.own-s{display:block;font:11.5px var(--f-mono);color:var(--muted);padding:0 12px 9px;min-height:1em}

/* ---- the build log, like a receipt from the bench */
.log{margin:14px 0;border:1px solid var(--line);border-radius:8px;background:var(--bg);padding:12px 14px;font-size:14px}
.log-h{display:flex;justify-content:space-between;gap:10px;font:600 11px var(--f-mono);letter-spacing:.06em;text-transform:uppercase;color:var(--muted);padding-bottom:8px;border-bottom:1px dashed var(--line);margin-bottom:8px}
.log-steps{list-style:none;margin:0;padding:0}
.log-steps li{display:grid;grid-template-columns:34px 1fr;column-gap:4px;padding:4px 0}
.log-steps code{font:13px var(--f-mono);color:var(--kc,var(--c2));background:none;padding:0;grid-row:span 2}
.log-steps q{font:400 18px/1.35 var(--f-serif);color:var(--ink);quotes:"“" "”"}
.log-steps .nope{font-size:12.5px;color:var(--muted);font-style:italic}
.log-words{margin-top:10px;border-top:1px dashed var(--line);padding-top:8px}
.log-words summary{cursor:pointer;font:600 11px var(--f-mono);letter-spacing:.06em;text-transform:uppercase;color:var(--muted)}
.log-words dl{display:grid;grid-template-columns:max-content 1fr;gap:6px 14px;margin:10px 0 0}
.log-words dt{font-weight:600;background:linear-gradient(transparent 60%,color-mix(in srgb,var(--pink) 26%,transparent) 0);align-self:start}
.log-words dd{margin:0;color:var(--muted);font-size:13.5px}
.log .btns{margin-top:10px}
@media (max-width:560px){.log-words dl{grid-template-columns:1fr}.log-words dd{margin-bottom:6px}}

/* Build X wiring map: keycaps on blueprint paper, wires light up when both ends are built */
.wiremap{margin:8px 0 26px}
.wm-scroll{overflow-x:auto;border:1px solid var(--line);border-radius:10px;padding:14px;
  background:linear-gradient(color-mix(in srgb,var(--kc,#e6a21a) 9%,transparent) 1px,transparent 1px) 0 0/16px 16px,
  linear-gradient(90deg,color-mix(in srgb,var(--kc,#e6a21a) 9%,transparent) 1px,transparent 1px) 0 0/16px 16px,var(--card)}
.wires{display:block;margin:0 auto;overflow:visible}
.wire{fill:none;stroke:var(--line);stroke-width:2;stroke-dasharray:3 4}
.wire.lit{stroke:var(--kc,#e6a21a);stroke-width:3;stroke-dasharray:10 6}
@media (prefers-reduced-motion:no-preference){.wire.lit{animation:wflow 1.2s linear infinite}}
@keyframes wflow{to{stroke-dashoffset:-16}}
.wnode .cap{fill:var(--panel);stroke:var(--line);stroke-width:1.5}
.wnode .wn{font:700 13px var(--f-display);fill:var(--muted)}
.wnode .wl{font:600 10.5px var(--f-body);fill:var(--ink)}
.wnode.s1 .cap{stroke:var(--kc,#e6a21a);stroke-width:2}
.wnode.s2 .cap{fill:var(--kc,#e6a21a);stroke:color-mix(in srgb,var(--kc,#e6a21a) 70%,#000)}
.wnode.s2 .wn,.wnode.s2 .wl{fill:#1b1a12}
.wnode:hover .cap{stroke:var(--kc,#e6a21a);stroke-width:2.5}
.wnode{transition:transform .15s}.wnode:hover{transform:translateY(-2px)}

/* Build X blueprint: one voxel part per step stacks into the machine; reuses / unlocks on the side */
.bp{display:flex;gap:18px;align-items:center;margin:14px 0 18px;padding:14px 18px;border:1px solid var(--line);border-radius:10px;
  background:linear-gradient(color-mix(in srgb,var(--kc,#e6a21a) 10%,transparent) 1px,transparent 1px) 0 0/14px 14px,
  linear-gradient(90deg,color-mix(in srgb,var(--kc,#e6a21a) 10%,transparent) 1px,transparent 1px) 0 0/14px 14px,var(--card)}
.bp-art{flex:none}.bp-art svg{display:block;max-width:150px;height:auto}
.bp-c path{stroke:var(--card);stroke-width:1}
.bp-c.todo path{fill:none;stroke:var(--line);stroke-dasharray:2 2}
.bp-c.done .t{fill:color-mix(in srgb,var(--kc,#e6a21a) 55%,#fff)}.bp-c.done .l{fill:var(--kc,#e6a21a)}.bp-c.done .r{fill:color-mix(in srgb,var(--kc,#e6a21a) 68%,#000)}
.bp-c.now .t{fill:#ffc4e1}.bp-c.now .l{fill:#ff6fb5}.bp-c.now .r{fill:#c2407f}
@media (prefers-reduced-motion:no-preference){.bp-c.now{animation:bpnow 1.4s ease-in-out infinite}}
@keyframes bpnow{50%{opacity:.45}}
.bp-txt{min-width:0}
.bp-eye{font:11px var(--f-mono);color:var(--muted)}
.bp-name{font:400 26px/1.1 "Instrument Serif",Georgia,serif;margin:2px 0}
.bp-name i{font:600 12px var(--f-mono);font-style:normal;color:var(--kc,#e6a21a);margin-left:6px;vertical-align:middle}
.bp-sub{margin:0 0 6px;font-size:13.5px;color:var(--muted)}
.bp-row{display:flex;flex-wrap:wrap;gap:6px;align-items:center;margin-top:4px}
.bp-row>span{font:11px var(--f-mono);color:var(--faint,var(--muted));width:56px}
.bp-chip{font:12px var(--f-body);text-decoration:none;color:var(--ink);background:var(--panel);border:1px solid var(--line);border-radius:6px;padding:2px 8px;box-shadow:inset 0 -2px 0 var(--line)}
.bp-chip b{font:700 12px var(--f-display);color:var(--kc,#e6a21a)}
.bp-chip:hover{border-color:var(--kc,#e6a21a)}
@media (max-width:560px){.bp{flex-direction:column;align-items:flex-start}}
/* the shipped stamp on the build log */
.log{position:relative}
.shipped{position:absolute;right:14px;top:-14px;transform:rotate(-6deg);font:700 15px var(--f-display);letter-spacing:.12em;text-transform:uppercase;
  color:#2fb34a;border:2.5px solid #2fb34a;border-radius:6px;padding:3px 10px;background:var(--card);text-align:center;line-height:1.1}
.shipped small{display:block;font:600 10px var(--f-mono);letter-spacing:0;text-transform:none}

/* running: the output dims, three blocks hop; done: the result slides in with a pink edge that fades */
.out.pending{display:block;position:relative;min-height:40px;color:color-mix(in srgb,currentColor 35%,transparent)}
.out.pending::after{content:"";position:absolute;left:12px;bottom:12px;width:8px;height:8px;background:#ff6fb5;border-radius:1px;
  box-shadow:12px 0 0 #ffd21f,24px 0 0 var(--kc,#3faa52);animation:hop .9s steps(3) infinite}
.out.pending:empty::before{content:"running";font:11px var(--f-mono);color:var(--muted);margin-left:36px;line-height:16px}
@keyframes hop{0%{transform:translateY(0)}33%{transform:translateY(-4px)}66%{transform:translateY(0)}}
.out.fresh{animation:outin .38s cubic-bezier(.2,.8,.3,1)}
@keyframes outin{from{opacity:0;transform:translateY(6px);box-shadow:inset 3px 0 0 #ff6fb5}to{opacity:1;transform:none;box-shadow:inset 3px 0 0 transparent}}
@media (prefers-reduced-motion:reduce){.out.pending::after,.out.fresh{animation:none}}

/* puzzle mode: Learn / Puzzle switch, keycap cells, stars */
.mode-sw{display:inline-flex;border:1px solid color-mix(in srgb,currentColor 35%,transparent);border-radius:999px;overflow:hidden;font-size:12.5px}
.mode-sw a{padding:3px 11px;color:inherit;text-decoration:none;opacity:.8}
.mode-sw a.on{background:var(--pink);color:#1d1b17;opacity:1;font-weight:600}
.badge.puzzle{background:var(--pink);color:#1d1b17}
.pboard{display:flex;flex-direction:column;gap:12px;align-items:flex-start;margin:6px 0 10px;overflow-x:auto;max-width:100%}
.prow{display:flex;gap:6px;align-items:center;flex-wrap:wrap}
.prow.goal{opacity:.75}
.plab{font:11px var(--f-mono);color:var(--muted);text-transform:uppercase;letter-spacing:.06em;min-width:34px}
.pgrid{display:grid;gap:3px}
.pc{min-width:38px;height:38px;padding:0 8px;border-radius:7px;border:1px solid var(--line);background:var(--card);box-shadow:0 3px 0 var(--line);display:inline-grid;place-items:center;font:600 14px var(--f-mono);color:var(--ink);cursor:pointer;transition:transform .08s,box-shadow .08s}
span.pc{cursor:default}
.pgrid .pc{min-width:30px;height:30px;padding:0 5px;font-size:12px;box-shadow:0 2px 0 var(--line)}
button.pc:active{transform:translateY(2px);box-shadow:0 1px 0 var(--line)}
.pc.e{background:var(--soft);box-shadow:none}
.pc.c1{background:var(--c1);border-color:var(--c1)}.pc.c2{background:var(--c2);border-color:var(--c2)}.pc.c3{background:var(--c3);border-color:var(--c3)}.pc.c4{background:var(--c4);border-color:var(--c4)}
.pc.sel{outline:3px solid var(--pink);outline-offset:1px}
.pc.mark{outline:3px solid var(--bad);outline-offset:1px}
.pc.good{border-color:var(--ok);box-shadow:0 3px 0 var(--ok)}
.pc.ghost{box-shadow:none;border-style:dashed}
.pnow{display:flex;gap:10px;align-items:center}
.popts{display:flex;gap:12px;flex-wrap:wrap}
.popt{display:flex;flex-direction:column;gap:6px;align-items:flex-start;padding:8px;border:1px solid var(--line);border-radius:10px;background:var(--card);cursor:pointer}
.popt:hover{border-color:var(--pink)}
.popt.right{border-color:var(--ok);box-shadow:0 0 0 2px var(--ok)}
.popt.wrong{border-color:var(--bad);opacity:.55}
.pcount{font:12px var(--f-mono);color:var(--muted);align-self:center}
.wrapln{white-space:normal!important}
.pslider{display:grid;grid-template-columns:minmax(120px,auto) minmax(140px,260px) 56px;gap:10px;align-items:center;font-size:14px}
.pslider output{font:13px var(--f-mono)}
.ptarget{width:min(100%,460px)}
.ptbar{position:relative;height:16px;border-radius:8px;background:var(--soft);border:1px solid var(--line)}
.ptbar .tgt{position:absolute;top:-1px;bottom:-1px;background:color-mix(in srgb,var(--ok) 35%,transparent);border-left:2px solid var(--ok);border-right:2px solid var(--ok)}
.ptbar b{position:absolute;top:-5px;width:6px;height:24px;margin-left:-3px;border-radius:3px;background:var(--c1);transition:left .12s}
.ptbar b.hit{background:var(--ok)}
.stars{display:inline-flex;gap:2px;vertical-align:-2px}
.stars i{width:12px;height:12px;background:var(--line);clip-path:polygon(50% 0,61% 35%,98% 35%,68% 57%,79% 91%,50% 70%,21% 91%,32% 57%,2% 35%,39% 35%)}
.stars i.on{background:var(--c4)}
.pstar{margin-left:auto}
.pwall{display:grid;grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:12px;margin-top:18px}
.pkey{display:flex;flex-direction:column;gap:6px;padding:12px;border:1px solid var(--line);border-radius:12px;background:var(--card);box-shadow:0 4px 0 var(--line);color:inherit;text-decoration:none}
.pkey:hover{border-color:var(--pink);box-shadow:0 4px 0 var(--pink)}
.pkey b{font:600 18px var(--f-display);color:var(--pink)}
.pkey span{font-size:13.5px;line-height:1.35}
@media (max-width:560px){.pslider{grid-template-columns:1fr 56px}.pslider span{grid-column:1/-1}.pc{min-width:34px;height:34px}}