/* TradeLabs Learn: the docs site at learn.tradelabsai.com. Same colours and type as tradelabsai.com (doc2.css tokens). */
/* IBM Plex, served from this site (SIL Open Font License): no outside request before the first paint */
@font-face{font-family:'IBM Plex Sans';font-style:normal;font-weight:400 700;font-display:swap;src:url(/assets/fonts/plex-sans.woff2) format('woff2')}
@font-face{font-family:'IBM Plex Mono';font-style:normal;font-weight:400;font-display:swap;src:url(/assets/fonts/plex-mono-400.woff2) format('woff2')}
@font-face{font-family:'IBM Plex Mono';font-style:normal;font-weight:500;font-display:swap;src:url(/assets/fonts/plex-mono-500.woff2) format('woff2')}
:root{
  --bg:#ffffff;--bg2:#f7f8fa;--card:#ffffff;--text:#14171f;--dim:#5b6270;--faint:#8a90a0;--line:#e6e8ef;--line2:#d5d8e2;
  --accent:#007a43;--accent-bg:rgba(0,181,101,.09);--neon:#00fe87;--red:#c81f42;--up:#089981;--down:#f23645;
  --code-bg:#0f1117;--code-text:#e6e7ec;--shadow:0 1px 2px rgba(16,24,40,.05),0 8px 24px rgba(16,24,40,.06);
  --sans:'IBM Plex Sans',ui-sans-serif,system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;
  --mono:'IBM Plex Mono',ui-monospace,'SF Mono',Menlo,Consolas,monospace;
  --ease:cubic-bezier(.23,1,.32,1);--top:64px;
}
html[data-theme="dark"]{
  --bg:#0a0a0f;--bg2:#0e0e15;--card:#111118;--text:#e6e7ec;--dim:#a3a8b5;--faint:#6f7586;--line:#1a1a2e;--line2:#252540;
  --accent:#00ff88;--accent-bg:rgba(0,255,136,.08);--red:#ff4466;--up:#26d9a6;--down:#ff5a6e;
  --code-bg:#07070b;--shadow:0 1px 2px rgba(0,0,0,.4),0 8px 28px rgba(0,0,0,.35);
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-padding-top:calc(var(--top) + 16px);-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--text);font:16px/1.7 var(--sans);-webkit-font-smoothing:antialiased;transition:background .25s,color .25s}
a{color:inherit}
svg{fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
.skip{position:absolute;left:-999px;top:8px;z-index:200;background:var(--neon);color:#000;padding:8px 14px;border-radius:8px}
.skip:focus{left:8px}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:6px}

/* ── top bar and area tabs ── */
.top{position:fixed;top:0;left:0;right:0;z-index:50;background:color-mix(in srgb,var(--bg) 88%,transparent);
  backdrop-filter:saturate(1.6) blur(14px);-webkit-backdrop-filter:saturate(1.6) blur(14px);border-bottom:1px solid var(--line)}
.top-in{height:64px;display:flex;align-items:center;gap:16px;padding:0 24px;max-width:1600px;margin:0 auto}
.brand{display:inline-flex;align-items:flex-end;gap:6px;text-decoration:none;font-weight:600;font-size:19px;letter-spacing:-.02em;line-height:1}
.brand .mark{width:15px;height:20px}
.mark rect{fill:var(--text);stroke:none}
.brand em{font-style:normal;font-size:11px;font-weight:600;letter-spacing:.04em;text-transform:uppercase;color:var(--accent);
  background:var(--accent-bg);border:1px solid color-mix(in srgb,var(--accent) 30%,transparent);border-radius:999px;padding:3px 8px;margin-left:4px;line-height:1}
kbd{font:500 11px var(--mono);border:1px solid var(--line2);border-bottom-width:2px;border-radius:5px;padding:1px 6px;color:var(--dim);background:var(--card)}
.top-r{margin-left:auto;display:flex;align-items:center;gap:10px}
.main-link{font-size:14px;color:var(--dim);text-decoration:none;padding:6px 8px;border-radius:8px;transition:color .2s}
.main-link:hover{color:var(--text)}
.top-nav{display:flex;align-items:center;gap:2px;margin-left:18px}
.top-nav>a{position:relative;font-size:14px;font-weight:500;color:var(--dim);text-decoration:none;padding:8px 12px;border-radius:9px;transition:color .2s var(--ease),background .2s var(--ease)}
.top-nav>a:hover{color:var(--text);background:var(--bg2)}
.top-nav>a.on{color:var(--text)}
.top-nav>a.on::after{content:"";position:absolute;left:12px;right:12px;bottom:2px;height:2px;border-radius:2px;background:var(--accent);animation:navin .5s var(--ease) both}
@keyframes navin{from{transform:scaleX(0)}to{transform:scaleX(1)}}
.acct{display:flex;align-items:center;gap:8px}
.acct-in{font-size:14px;font-weight:500;color:var(--text);text-decoration:none;padding:8px 12px;border-radius:9px;transition:background .2s var(--ease)}
.acct-in:hover{background:var(--bg2)}
.acct-me{display:inline-flex;align-items:center;gap:8px;height:38px;padding:0 12px 0 6px;border:1px solid var(--line);border-radius:999px;color:var(--text);text-decoration:none;font-size:14px;font-weight:500;transition:border-color .2s var(--ease)}
.acct-me:hover{border-color:var(--accent)}
.acct-me i{width:26px;height:26px;border-radius:50%;display:grid;place-items:center;background:var(--accent-bg);color:var(--accent);font-style:normal;font-weight:700;font-size:13px}
.side-links{display:none}
.icon-btn{width:38px;height:38px;display:inline-grid;place-items:center;border-radius:10px;border:1px solid var(--line);background:transparent;color:var(--dim);cursor:pointer;transition:color .2s,border-color .2s,transform .2s var(--ease)}
.icon-btn:hover{color:var(--text);border-color:var(--line2)}
.icon-btn:active{transform:scale(.94)}
.icon-btn svg{width:18px;height:18px}
html[data-theme="dark"] .i-moon,html:not([data-theme="dark"]) .i-sun{display:none}
.menu-btn{display:none}
.search-sm{display:none}
.cta{display:inline-flex;align-items:center;gap:8px;height:38px;padding:0 16px;border-radius:999px;background:var(--neon);color:#000;
  font-weight:600;font-size:14px;text-decoration:none;box-shadow:0 0 0 0 rgba(0,254,135,.5);transition:transform .2s var(--ease),box-shadow .3s}
.cta:hover{transform:translateY(-1px);box-shadow:0 6px 20px -6px rgba(0,254,135,.7)}
.cta svg{width:16px;height:16px}
/* ── layout ── */
.wrap{display:grid;grid-template-columns:280px minmax(0,1fr);max-width:1600px;margin:0 auto;padding-top:var(--top)}
.wrap.wide{grid-template-columns:280px minmax(0,1fr)}
.side{position:sticky;top:var(--top);height:calc(100vh - var(--top));border-right:1px solid var(--line)}
.side-in{height:100%;overflow-y:auto;padding:28px 18px 60px 24px}
.side-in{padding-top:18px}
.side-search{position:sticky;top:0;z-index:2;width:100%;display:flex;align-items:center;gap:10px;height:40px;padding:0 10px 0 12px;margin:0 0 18px;
  border-radius:10px;border:1px solid var(--line);background:var(--bg2);color:var(--faint);font:inherit;font-size:14px;cursor:pointer;
  box-shadow:0 -18px 0 var(--bg);transition:border-color .2s,box-shadow .2s}
.side-search:hover{border-color:var(--line2)}
.side-search svg{width:16px;height:16px}
.side-search span{flex:1;text-align:left}
.area-h{font-size:11px;font-weight:600;letter-spacing:.08em;text-transform:uppercase;color:var(--faint);margin:22px 0 6px 10px}
.area-h:first-of-type{margin-top:4px}
.grp{margin:0 0 2px}
.grp summary{display:flex;align-items:center;gap:8px;list-style:none;cursor:pointer;font-size:14px;font-weight:500;color:var(--text);
  padding:7px 10px;border-radius:8px;transition:background .15s;user-select:none}
.grp summary::-webkit-details-marker{display:none}
.grp summary:hover{background:var(--bg2)}
.grp summary span{flex:1}
.grp summary small{font-size:11px;color:var(--faint);font-weight:500;border:1px solid var(--line);border-radius:999px;padding:0 7px;line-height:18px}
.chev{width:14px;height:14px;flex:0 0 14px;color:var(--faint);transition:transform .2s var(--ease)}
.grp[open] > summary .chev{transform:rotate(90deg)}
.grp ul{list-style:none;margin:2px 0 10px 16px;padding:0 0 0 8px;border-left:1px solid var(--line)}
.grp[open] ul{animation:rise .25s var(--ease) both}
.grp li.sec{font-size:10.5px;font-weight:600;letter-spacing:.07em;text-transform:uppercase;color:var(--faint);margin:12px 0 3px 10px}
.grp li a{display:block;font-size:13.5px;line-height:1.45;color:var(--dim);text-decoration:none;padding:6px 10px;border-radius:8px;transition:color .15s,background .15s}
.grp li a:hover{color:var(--text);background:var(--bg2)}
.grp li a.on{color:var(--accent);background:var(--accent-bg);font-weight:500}
.main{display:grid;grid-template-columns:minmax(0,760px) 220px;gap:56px;justify-content:center;padding:44px 40px 80px;min-width:0}
.main.home,.main:has(> .doc:only-child){grid-template-columns:minmax(0,1040px)}
.scrim{display:none}

/* ── the lesson ── */
.doc{min-width:0;animation:rise .5s var(--ease) both}
@keyframes rise{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}
.crumbs{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--accent);font-weight:500;margin-bottom:10px}
.crumbs a{text-decoration:none}.crumbs a:hover{text-decoration:underline}
.crumbs i{font-style:normal;color:var(--faint)}
.crumbs span{color:var(--dim)}
.doc h1{font-size:clamp(30px,4vw,40px);line-height:1.15;letter-spacing:-.025em;font-weight:700;margin:0 0 12px}
.lede{font-size:18px;line-height:1.6;color:var(--dim);margin:0 0 18px}
.meta{display:flex;flex-wrap:wrap;align-items:center;gap:8px 16px;font-size:13px;color:var(--faint);padding-bottom:22px;border-bottom:1px solid var(--line);margin-bottom:8px}
.lvl{display:inline-flex;align-items:center;font-size:11px;font-weight:600;letter-spacing:.05em;text-transform:uppercase;border-radius:999px;padding:3px 9px;border:1px solid}
.lvl.beginner{color:var(--accent);border-color:color-mix(in srgb,var(--accent) 35%,transparent);background:var(--accent-bg)}
.lvl.intermediate{color:#b26b00;border-color:rgba(214,140,0,.35);background:rgba(214,140,0,.08)}
.lvl.advanced{color:#8a3ffc;border-color:rgba(138,63,252,.35);background:rgba(138,63,252,.08)}
html[data-theme="dark"] .lvl.intermediate{color:#f5b84a}
html[data-theme="dark"] .lvl.advanced{color:#b78cff}
.before{display:flex;flex-wrap:wrap;align-items:center;gap:8px;margin:18px 0 0;font-size:13px}
.before span{color:var(--faint);margin-right:2px}
.before a{text-decoration:none;color:var(--text);border:1px solid var(--line);border-radius:999px;padding:4px 12px;transition:border-color .2s,color .2s}
.before a:hover{border-color:var(--accent);color:var(--accent)}

.prose{font-size:16.5px;padding-top:20px}
.prose h2{font-size:24px;line-height:1.3;letter-spacing:-.015em;margin:44px 0 12px;font-weight:650}
.prose h3{font-size:19px;line-height:1.35;margin:30px 0 8px;font-weight:600}
.prose h2,.prose h3{position:relative}
.anchor{opacity:0;margin-left:8px;color:var(--faint);text-decoration:none;font-weight:400;transition:opacity .15s}
.prose h2:hover .anchor,.prose h3:hover .anchor{opacity:1}
.prose p{margin:0 0 18px}
.prose ul,.prose ol{margin:0 0 20px;padding-left:22px}
.prose li{margin:6px 0;padding-left:4px}
.prose li::marker{color:var(--accent)}
.prose strong{font-weight:600;color:var(--text)}
.prose a:not(.next-card):not(.ext):not(.tl-link){color:var(--accent);text-decoration:underline;text-decoration-thickness:1px;text-underline-offset:3px;text-decoration-color:color-mix(in srgb,var(--accent) 40%,transparent)}
.prose a:hover{text-decoration-color:currentColor}
.prose a.ext,.prose a.tl-link{color:var(--accent);text-decoration:underline;text-underline-offset:3px;text-decoration-thickness:1px;text-decoration-color:color-mix(in srgb,var(--accent) 40%,transparent)}
.ext svg{width:12px;height:12px;margin-left:2px;vertical-align:1px;opacity:.7}
.prose code{font:500 .86em var(--mono);background:var(--bg2);border:1px solid var(--line);border-radius:6px;padding:1px 6px}
.prose pre{background:var(--code-bg);color:var(--code-text);border-radius:12px;padding:18px 20px;overflow-x:auto;margin:0 0 22px;border:1px solid var(--line)}
.prose pre code{background:none;border:0;padding:0;color:inherit;font-size:14px;line-height:1.65}
.prose pre.formula{background:var(--accent-bg);color:var(--text);border-color:color-mix(in srgb,var(--accent) 25%,transparent);text-align:center}
.prose pre.formula code{font-size:16px;font-weight:500}
.prose blockquote{margin:0 0 20px;padding:4px 0 4px 18px;border-left:3px solid var(--accent);color:var(--dim)}
.prose blockquote p{margin:0}
.table{overflow-x:auto;margin:0 0 24px;border:1px solid var(--line);border-radius:12px}
.prose table{width:100%;border-collapse:collapse;font-size:14.5px}
.prose th{text-align:left;font-weight:600;background:var(--bg2);padding:11px 14px;border-bottom:1px solid var(--line);white-space:nowrap}
.prose td{padding:11px 14px;border-bottom:1px solid var(--line);vertical-align:top}
.prose tr:last-child td{border-bottom:0}
.callout{display:flex;gap:12px;margin:0 0 22px;padding:14px 16px;border-radius:12px;border:1px solid var(--line);background:var(--bg2)}
.callout .ci{flex:0 0 22px;padding-top:2px}
.callout .ci svg{width:20px;height:20px}
.callout .cb{min-width:0}
.callout .ct{font-weight:600;font-size:15px;margin-bottom:2px}
.callout .cb p:last-child,.callout .cb ul:last-child{margin-bottom:0}
.callout.tip{border-color:color-mix(in srgb,var(--accent) 30%,transparent);background:var(--accent-bg)}
.callout.tip .ci{color:var(--accent)}
.callout.note .ci{color:#2f7cf6}
.callout.note{border-color:rgba(47,124,246,.28);background:rgba(47,124,246,.06)}
.callout.warning{border-color:rgba(214,140,0,.32);background:rgba(214,140,0,.07)}
.callout.warning .ci{color:#d68c00}
.callout.example .ci{color:var(--dim)}
.progress{display:flex;align-items:center;gap:12px;margin:0 0 22px;font-size:12.5px;color:var(--faint)}
.progress i{flex:1;max-width:220px;height:4px;border-radius:4px;background:var(--line);overflow:hidden}
.progress b{display:block;height:100%;background:var(--accent);border-radius:4px;animation:progin .9s var(--ease) both}
@keyframes progin{from{transform:scaleX(0);transform-origin:left}to{transform:scaleX(1);transform-origin:left}}
.paths{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:16px;margin:28px 0 8px}
.paths div{border:1px solid var(--line);border-radius:12px;padding:16px 18px;background:var(--bg2)}
.paths h3{margin:0 0 10px;font-size:13px;text-transform:uppercase;letter-spacing:.05em;color:var(--faint)}
.paths ul{list-style:none;margin:0;padding:0}
.paths li{padding:7px 0;border-top:1px solid var(--line)}
.paths li:first-child{border-top:0}
.paths a{color:var(--text);text-decoration:none;font-weight:500;transition:color .2s var(--ease)}
.paths a:hover{color:var(--accent)}
.paths small{display:block;font-size:12px;color:var(--faint)}
@media (prefers-reduced-motion:reduce){.progress b{animation:none}}
.page-tools{display:flex;flex-wrap:wrap;gap:8px;margin:-6px 0 22px}
.pt-btn{display:inline-flex;align-items:center;height:30px;padding:0 12px;border:1px solid var(--line2);border-radius:8px;background:var(--card);color:var(--dim);font:500 13px var(--sans);text-decoration:none;cursor:pointer;transition:color .2s var(--ease),border-color .2s var(--ease),background .2s var(--ease),transform .15s var(--ease)}
.pt-btn:hover{color:var(--text);border-color:var(--accent)}
.pt-btn:active{transform:scale(.97)}
.pt-btn.ok,.copy-btn.ok{color:var(--accent);border-color:var(--accent);background:var(--accent-bg)}
.prose pre{position:relative}
.copy-btn{position:absolute;top:8px;right:8px;height:26px;padding:0 10px;border:1px solid rgba(255,255,255,.14);border-radius:7px;background:rgba(255,255,255,.06);color:var(--code-text);font:500 12px var(--sans);cursor:pointer;opacity:.7;transition:opacity .2s var(--ease),background .2s var(--ease)}
.prose pre:hover .copy-btn,.copy-btn:focus{opacity:1}
.calc-bar{display:flex;justify-content:flex-end;padding:10px 18px;border-top:1px solid var(--line);background:var(--card)}
.calc{margin:6px 0 28px;border:1px solid var(--line);border-radius:14px;background:var(--card);box-shadow:var(--shadow);overflow:hidden}
.calc-in{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:14px;padding:18px}
.calc label{display:flex;flex-direction:column;gap:6px;font-size:13px;font-weight:500;color:var(--dim)}
.calc input,.calc select,.calc textarea{width:100%;box-sizing:border-box;height:40px;padding:0 12px;border:1px solid var(--line2);border-radius:9px;background:var(--bg);color:var(--text);font:15px var(--mono);transition:border-color .2s var(--ease),box-shadow .2s var(--ease)}
.calc textarea{height:72px;padding:9px 12px;resize:vertical}
.calc label.wide{grid-column:1/-1}
.calc input:focus,.calc select:focus,.calc textarea:focus{outline:0;border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-bg)}
.calc-out{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:1px;margin:0;background:var(--line);border-top:1px solid var(--line)}
.calc-out div{background:var(--bg2);padding:14px 18px}
.calc-out dt{font-size:12px;color:var(--faint);text-transform:uppercase;letter-spacing:.04em}
.calc-out dd{margin:4px 0 0;font:600 19px var(--mono);color:var(--text);transition:color .25s var(--ease)}
.calc-out dd.pos{color:var(--up)}
.calc-out dd.neg{color:var(--down)}
.calc-out .flash{animation:calcflash .5s var(--ease)}
@keyframes calcflash{from{background:var(--accent-bg)}to{background:var(--bg2)}}
.calc-note{margin:0;padding:12px 18px;font-size:13px;color:var(--faint);border-top:1px solid var(--line)}
.calc-table{width:100%;border-collapse:collapse;font:14px var(--mono)}
.calc-table td,.calc-table th{padding:8px 18px;border-top:1px solid var(--line);text-align:right}
.calc-table th{font:600 12px var(--sans);color:var(--faint);text-transform:uppercase;letter-spacing:.04em;background:var(--bg2)}
.calc-table td:first-child,.calc-table th:first-child{text-align:left}
@media (prefers-reduced-motion:reduce){.calc-out .flash{animation:none}}
figure.fig{margin:6px 0 26px;border:1px solid var(--line);border-radius:14px;background:var(--card);padding:18px;overflow-x:auto}
figure.fig svg{display:block;width:100%;height:auto;max-width:680px;margin:0 auto;stroke-width:1.5}
figure.fig figcaption{font-size:13px;color:var(--faint);text-align:center;margin-top:10px}
.fig .t{fill:var(--text);stroke:none;font:500 12px var(--sans)}
.fig .d{fill:var(--dim);stroke:none;font:400 11px var(--sans)}
.fig .ln{stroke:var(--line2)}
.fig .up{fill:var(--up);stroke:var(--up)}
.fig .dn{fill:var(--down);stroke:var(--down)}
.fig .upo{fill:none;stroke:var(--up)}
.fig .acc{stroke:var(--accent)}
.fig .accf{fill:var(--accent);stroke:none}
.fig .box{fill:var(--bg2);stroke:var(--line2)}

/* ── after the lesson ── */
.next-card{position:relative;display:block;margin:40px 0 0;padding:20px 56px 20px 22px;border-radius:14px;border:1px solid var(--line);
  text-decoration:none;background:linear-gradient(135deg,var(--accent-bg),transparent 70%);transition:border-color .2s,transform .25s var(--ease),box-shadow .25s}
.next-card:hover{border-color:color-mix(in srgb,var(--accent) 50%,transparent);transform:translateY(-2px);box-shadow:var(--shadow)}
.next-card span{display:block;font-size:12px;font-weight:600;letter-spacing:.06em;text-transform:uppercase;color:var(--accent)}
.next-card b{display:block;font-size:19px;margin:4px 0 2px}
.next-card small{display:block;font-size:14px;color:var(--dim);line-height:1.5}
.next-card svg{position:absolute;right:20px;top:50%;width:22px;height:22px;margin-top:-11px;color:var(--accent);transition:transform .25s var(--ease)}
.next-card:hover svg{transform:translateX(4px)}
.related{margin-top:40px}
.rel-h{font-size:15px;font-weight:600;margin:0 0 12px}
.rel-g,.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:12px}
.rel-g a,.card{display:block;padding:15px 16px;border:1px solid var(--line);border-radius:12px;text-decoration:none;background:var(--card);transition:border-color .2s,transform .25s var(--ease),box-shadow .25s}
.rel-g a:hover,.card:hover{border-color:color-mix(in srgb,var(--accent) 45%,transparent);transform:translateY(-2px);box-shadow:var(--shadow)}
.rel-g b,.card b{display:block;font-size:15px;line-height:1.35;margin-bottom:4px}
.card .lvl{margin-bottom:10px}
.rel-g small,.card small{display:block;font-size:13px;color:var(--dim);line-height:1.5}
.prose .cards{margin-bottom:10px}
.pager{display:flex;justify-content:space-between;gap:12px;margin-top:40px;padding-top:24px;border-top:1px solid var(--line)}
.pager a{display:flex;align-items:center;gap:12px;max-width:48%;text-decoration:none;padding:10px 12px;border-radius:10px;transition:background .2s}
.pager a:hover{background:var(--bg2)}
.pager .nx{text-align:right;margin-left:auto}
.pager small{display:block;font-size:12px;color:var(--faint)}
.pager span{font-size:15px;font-weight:500;line-height:1.35}
.pager svg{width:18px;height:18px;flex:0 0 18px;color:var(--faint)}

/* ── on this page ── */
.toc{position:sticky;top:calc(var(--top) + 44px);align-self:start;max-height:calc(100vh - var(--top) - 80px);overflow-y:auto;font-size:13px}
.toc-h{font-weight:600;color:var(--text);margin-bottom:10px}
.toc ul{list-style:none;margin:0;padding:0;border-left:1px solid var(--line)}
.toc li a{display:block;padding:5px 0 5px 14px;margin-left:-1px;border-left:2px solid transparent;color:var(--dim);text-decoration:none;line-height:1.45;transition:color .15s,border-color .15s}
.toc li.l3 a{padding-left:26px}
.toc li a:hover{color:var(--text)}
.toc li a.on{color:var(--accent);border-left-color:var(--accent)}

/* ── home ── */
.hero{padding:20px 0 30px;border-bottom:1px solid var(--line);margin-bottom:34px;position:relative}
.hero::before{content:"";position:absolute;inset:-60px -40px auto auto;width:420px;height:300px;pointer-events:none;
  background:radial-gradient(closest-side,rgba(0,254,135,.18),transparent);filter:blur(10px);animation:glow 9s ease-in-out infinite alternate}
@keyframes glow{from{transform:translate(0,0)}to{transform:translate(-60px,30px)}}
.eyebrow{font-size:12px;font-weight:600;letter-spacing:.08em;text-transform:uppercase;color:var(--accent);margin-bottom:12px}
.hero h1{font-size:clamp(34px,5vw,52px);line-height:1.08;letter-spacing:-.03em;margin:0 0 16px;max-width:760px}
.hero .lede{max-width:680px}
.hero-a{display:flex;flex-wrap:wrap;gap:10px;margin-top:22px}
.btn{display:inline-flex;align-items:center;gap:8px;height:44px;padding:0 20px;border-radius:999px;background:var(--neon);color:#000;font:600 15px var(--sans);text-decoration:none;border:0;cursor:pointer;transition:transform .2s var(--ease),box-shadow .3s}
.btn:hover{transform:translateY(-1px);box-shadow:0 8px 24px -8px rgba(0,254,135,.8)}
.btn svg{width:17px;height:17px}
.btn.ghost{background:transparent;color:var(--text);border:1px solid var(--line2)}
.btn.ghost:hover{box-shadow:none;border-color:var(--accent)}
.area{margin-bottom:36px}
.area h2{font-size:13px;font-weight:600;letter-spacing:.07em;text-transform:uppercase;color:var(--faint);margin:0 0 12px}
.trks{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:12px}
.trk{display:flex;flex-direction:column;gap:4px;padding:16px;border:1px solid var(--line);border-radius:12px;text-decoration:none;background:var(--card);transition:border-color .2s,transform .25s var(--ease),box-shadow .25s}
.trk:hover{border-color:color-mix(in srgb,var(--accent) 45%,transparent);transform:translateY(-2px);box-shadow:var(--shadow)}
.trk b{font-size:16px}
.trk small{font-size:13px;color:var(--dim)}
.nf{padding:40px 0}

/* ── footer ── */
.n3-foot{--n3-bg:#f7f7fb;--n3-bg-2:#eef0f5;--n3-ink:#14171f;--n3-ink-2:#4b5563;--n3-ink-3:#6b7280;--n3-line:#e6e8ef;
  padding:64px 0 40px;border-top:1px solid var(--n3-line);background:var(--n3-bg);font-family:var(--sans)}
html[data-theme="dark"] .n3-foot{--n3-bg:#0a0a0f;--n3-bg-2:#0e0e15;--n3-ink:#e6e6ef;--n3-ink-2:#a8a8b8;--n3-ink-3:#7c7c92;--n3-line:#1a1a2e}
.n3-wrap{width:100%;max-width:calc(1200px + clamp(18px,4vw,40px)*2);margin:0 auto;padding:0 clamp(18px,4vw,40px);box-sizing:border-box}
.n3-foot-grid{display:grid;grid-template-columns:minmax(0,4fr) repeat(4,minmax(0,2fr));gap:36px 28px}
.n3-tn-brand{display:inline-flex;align-items:center;gap:9px;text-decoration:none;color:var(--n3-ink)}
.n3-tn-brand svg{width:22px;height:22px}
.n3-tn-brand span{font-size:17px;font-weight:600;letter-spacing:-.02em}
.n3-foot-brand p{margin:14px 0 0;font-size:14px;color:var(--n3-ink-3);max-width:24em;line-height:1.55}
.n3-foot h2{font-size:13px;font-family:var(--mono);font-weight:500;color:var(--n3-ink-3);margin:0 0 12px;letter-spacing:0}
.n3-foot ul{list-style:none;margin:0;padding:0;display:grid;gap:2px}
.n3-foot ul a{display:inline-flex;align-items:center;min-height:32px;color:var(--n3-ink-2);text-decoration:none;font-size:14.5px}
.n3-foot ul a:hover,.n3-foot ul a[aria-current]{color:var(--n3-ink);text-decoration:underline;text-underline-offset:3px}
.n3-foot-risk{max-width:56em;margin:28px auto 0;font-size:12px;line-height:1.6;color:var(--n3-ink-3);text-align:center}
.n3-foot-risk a{color:var(--n3-ink-2)}
.n3-foot-base{display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:16px;margin-top:48px;padding-top:24px;border-top:1px solid var(--n3-line);font-size:13.5px;color:var(--n3-ink-3)}
.n3-tl-socials{display:flex;gap:2px}
.n3-tl-social{display:inline-grid;place-items:center;width:40px;height:40px;border-radius:8px;color:var(--n3-ink-3);transition:color .2s,background .2s}
.n3-tl-social:hover{color:var(--n3-ink);background:var(--n3-bg-2)}
.n3-tl-social svg{width:18px;height:18px;fill:currentColor}
@media (max-width:900px){.n3-foot-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.n3-foot-brand{grid-column:1/-1}}

/* ── search ── */
.sm{position:fixed;inset:0;z-index:100;background:rgba(5,6,10,.45);backdrop-filter:blur(4px);display:flex;justify-content:center;align-items:flex-start;padding:12vh 16px 16px}
.sm[hidden]{display:none}
.sm-box{width:100%;max-width:620px;background:var(--card);border:1px solid var(--line);border-radius:16px;box-shadow:0 24px 60px rgba(0,0,0,.3);overflow:hidden;animation:pop .2s var(--ease)}
@keyframes pop{from{opacity:0;transform:translateY(-6px) scale(.98)}to{opacity:1;transform:none}}
.sm-in{display:flex;align-items:center;gap:10px;padding:0 16px;border-bottom:1px solid var(--line)}
.sm-in svg{width:18px;height:18px;color:var(--faint)}
.sm-in input{flex:1;height:56px;border:0;outline:0;background:transparent;color:var(--text);font:16px var(--sans)}
.sm-res{max-height:56vh;overflow-y:auto;padding:8px}
.sm-res a{display:block;padding:10px 12px;border-radius:10px;text-decoration:none}
.sm-res a.on,.sm-res a:hover{background:var(--accent-bg)}
.sm-res b{display:block;font-size:15px;font-weight:600}
.sm-res small{display:block;font-size:13px;color:var(--dim);line-height:1.45}
.sm-res i{font-style:normal;font-size:11px;color:var(--accent);font-weight:600;letter-spacing:.05em;text-transform:uppercase}
.sm-empty{padding:22px;text-align:center;color:var(--faint);font-size:14px}

/* ── narrower screens ── */
@media (max-width:1180px){.main{grid-template-columns:minmax(0,760px)}.toc{display:none}}
@media (max-width:900px){
  :root{--top:60px}
  .wrap,.wrap.wide{grid-template-columns:minmax(0,1fr)}
  .menu-btn{display:inline-grid}
  .side{position:fixed;top:var(--top);left:0;bottom:0;width:300px;max-width:85vw;height:auto;z-index:40;background:var(--bg);transform:translateX(-102%);transition:transform .3s var(--ease);border-right:1px solid var(--line)}
  body.menu-open .side{transform:none}
  body.menu-open .scrim{display:block;position:fixed;inset:var(--top) 0 0 0;z-index:30;background:rgba(5,6,10,.4)}
  .main{padding:28px 16px 64px}
  .search-sm{display:inline-grid}
  .main-link{display:none}
  .top-nav{display:none}.acct-in{display:none}.acct-me b{display:none}.acct-me{padding:0 6px}
  .side-links{display:grid;grid-template-columns:1fr 1fr;gap:6px;margin:0 0 14px}
  .side-links a{padding:9px 12px;border:1px solid var(--line);border-radius:9px;color:var(--text);text-decoration:none;font-size:14px;font-weight:500;text-align:center}
  .top-in{padding:0 16px;gap:10px;height:60px}
  .cta{padding:0 14px;font-size:13.5px}
  .cta[data-signup] span{font-size:0}.cta[data-signup] span::after{content:"Sign up";font-size:13.5px}
}
@media (max-width:520px){.brand em{display:none}.pager a{max-width:100%}.pager{flex-direction:column}.pager .nx{margin-left:0}}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}}
/* quiz, finishing a lesson, progress and the sign-in reminder */
.quiz{margin:34px 0 0;border:1px solid var(--line);border-radius:14px;background:var(--card);padding:20px 22px;box-shadow:var(--shadow)}
.quiz-h{font-size:20px;font-weight:600;letter-spacing:-.01em}
.quiz-sub{margin:4px 0 14px;color:var(--dim);font-size:14px}
.qz{padding:14px 0;border-top:1px solid var(--line)}
.qz-q{margin:0 0 10px;font-weight:600}
.qz-o{display:block;width:100%;text-align:left;margin:0 0 8px;padding:11px 14px;border:1px solid var(--line2);border-radius:10px;background:var(--bg);color:var(--text);font:14.5px/1.5 var(--sans);cursor:pointer;transition:border-color .2s var(--ease),background .2s var(--ease),transform .15s var(--ease)}
.qz-o:hover:not(:disabled){border-color:var(--accent);transform:translateX(3px)}
.qz-o:disabled{cursor:default}
.qz-o.right{border-color:var(--up);background:color-mix(in srgb,var(--up) 12%,transparent);animation:qzpop .35s var(--ease)}
.qz-o.wrong{border-color:var(--down);background:color-mix(in srgb,var(--down) 10%,transparent);animation:qzshake .35s var(--ease)}
@keyframes qzpop{50%{transform:scale(1.015)}}
@keyframes qzshake{25%{transform:translateX(-4px)}75%{transform:translateX(4px)}}
.qz-res{display:flex;flex-wrap:wrap;align-items:center;gap:10px;padding-top:14px;border-top:1px solid var(--line)}
.finish{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:14px;margin:22px 0 0;padding:16px 20px;border:1px dashed var(--line2);border-radius:14px;transition:border-color .3s var(--ease),background .3s var(--ease)}
.finish-t{display:flex;flex-direction:column;gap:2px}
.finish-t span{font-size:13.5px;color:var(--dim)}
.finish.is-done{border-style:solid;border-color:var(--accent);background:var(--accent-bg)}
.finish.is-done .finish-btn{color:var(--accent);border-color:var(--accent)}
.side a.done::after,.card.done b::after,.rel-g a.done b::after,.paths a.done::after{content:"";display:inline-block;width:7px;height:12px;margin-left:8px;border:solid var(--accent);border-width:0 2px 2px 0;transform:rotate(45deg) translateY(-2px)}
.next-card.done{border-color:var(--accent)}
.side summary small.some{color:var(--accent)}
i.bar{display:block;height:6px;border-radius:6px;background:var(--line);overflow:hidden}
i.bar b{display:block;height:100%;border-radius:6px;background:var(--accent);animation:progin .9s var(--ease) both}
.tp{margin:-4px 0 24px;padding:14px 18px;border:1px solid var(--line);border-radius:12px;background:var(--bg2)}
.tp-row{display:flex;align-items:center;gap:14px}.tp-row i.bar{flex:1}
.tp-next{display:inline-block;margin-top:10px;font-size:14px;color:var(--accent);text-decoration:none}
.tp-sign{font-size:14px;color:var(--dim);text-decoration:none}.tp-sign:hover{color:var(--accent)}
.yp{margin:8px 0 34px;padding:22px 24px;border:1px solid var(--line);border-radius:16px;background:var(--card);box-shadow:var(--shadow)}
.yp-h{display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:space-between;gap:14px;margin-bottom:14px}
.yp-h h2{margin:4px 0 0;font-size:24px}
.yp-g{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:12px;margin-top:18px}
.yp-t{display:flex;flex-direction:column;gap:6px;padding:14px;border:1px solid var(--line);border-radius:12px;color:var(--text);text-decoration:none;transition:border-color .2s var(--ease),transform .2s var(--ease)}
.yp-t:hover{border-color:var(--accent);transform:translateY(-2px)}
.yp-t small{color:var(--faint)}
.yp-empty{margin:14px 0 0;color:var(--dim)}
.nudge{position:fixed;right:20px;bottom:20px;z-index:80;width:min(460px,calc(100vw - 40px));padding:18px 20px 12px;border:1px solid var(--line2);border-radius:14px;background:var(--card);box-shadow:0 16px 48px -18px rgba(0,0,0,.35);opacity:0;transform:translateY(16px);transition:opacity .3s var(--ease),transform .3s var(--ease)}
.nudge.in{opacity:1;transform:none}
.nudge-h{padding-right:28px}
.nudge-list i{display:none;font-style:normal}
.nudge-h{display:block;font-size:16px;font-weight:600}
.nudge p{margin:4px 0 8px;font-size:14px;color:var(--dim);line-height:1.5}
.nudge-list{list-style:none;margin:0;padding:0;display:flex;flex-wrap:nowrap;white-space:nowrap;overflow:hidden;font-size:12.5px;color:var(--faint)}
.nudge-list li{white-space:nowrap}
.nudge-list li:not(:last-child)::after{content:"\00B7";margin:0 7px;color:var(--line2)}
.nudge-a{display:flex;gap:8px;margin-top:14px}
.nudge-go,.nudge-in{display:inline-flex;align-items:center;justify-content:center;height:34px;padding:0 16px;border-radius:9px;font:600 13.5px var(--sans);text-decoration:none;white-space:nowrap;transition:background .2s var(--ease),border-color .2s var(--ease),transform .15s var(--ease)}
.nudge-go{flex:1.4;background:var(--neon);color:#04120b}
.nudge-go:hover{background:#00e577}
.nudge-in{flex:1;border:1px solid var(--line2);color:var(--text)}
.nudge-in:hover{border-color:var(--text)}
.nudge-go:active,.nudge-in:active{transform:scale(.98)}
.nudge-skip{display:block;width:100%;margin:10px 0 0;padding:2px 0;border:0;background:none;font:400 12.5px/1.45 var(--sans);white-space:nowrap;overflow:hidden;text-overflow:ellipsis;color:var(--faint);text-align:center;text-decoration:underline;text-underline-offset:3px;cursor:pointer}
.nudge-skip:hover{color:var(--text)}
.nudge-x{position:absolute;top:12px;right:12px;width:28px;height:28px;border:0;border-radius:7px;background:transparent;color:var(--faint);font-size:19px;cursor:pointer}
.nudge-x:hover{color:var(--text);background:var(--bg2)}
@media (max-width:700px){.nudge{right:16px;bottom:16px;width:calc(100vw - 32px);padding:18px 18px 12px}}
@media (max-width:480px){.nudge-list span{display:none}.nudge-list i{display:inline}.nudge-skip{font-size:12px}}
/* header menus: the tradelabsai.com menus (site-nav.css, "nav1" compact panels), same markup and look */
.top-nav .tn-item{position:relative;display:flex;align-items:center}
.top-nav .tn-link{display:inline-flex;align-items:center;font:500 14px var(--sans);color:var(--dim);background:none;border:0;padding:8px 12px;border-radius:9px;cursor:pointer;white-space:nowrap;transition:color .2s var(--ease),background .2s var(--ease)}
.top-nav .tn-item.open>.tn-link,.top-nav .tn-link:hover{color:var(--text);background:var(--bg2)}
.tn-caret{display:inline-block;width:0;height:0;border-left:3.5px solid transparent;border-right:3.5px solid transparent;border-top:4.5px solid currentColor;margin-left:.4rem;opacity:.7;transition:transform .2s}
.tn-item.open .tn-caret{transform:rotate(180deg)}
.tn-mega{position:fixed;top:var(--top);left:0;display:none;flex-direction:column;align-items:stretch;width:auto;max-width:calc(100vw - 32px);margin-top:6px;padding:0;border:1px solid #e5e7eb;border-radius:14px;box-shadow:0 18px 50px -12px rgba(16,19,18,.24);background:#fff;z-index:999;text-align:left;font-family:-apple-system,BlinkMacSystemFont,'Inter','Segoe UI',sans-serif;animation:tnin .18s var(--ease)}
@keyframes tnin{from{opacity:0;transform:translateY(4px)}to{opacity:1;transform:none}}
.tn-mega::before{content:"";position:absolute;left:0;right:0;top:-10px;height:10px}
.tn-item.open .tn-mega{display:flex}
.tn-wrap{display:block}
.tn-side{display:none}
.tn-cols{display:grid;grid-auto-flow:column;grid-auto-columns:minmax(230px,270px);gap:0 .4rem;padding:.6rem .6rem .35rem}
.tn-col{display:flex;flex-direction:column}
.tn-h{color:#00b565;font-size:.6rem;font-weight:600;text-transform:uppercase;letter-spacing:.1em;padding:.4rem .6rem .2rem;margin:0}
.tn-dd-item{display:flex;align-items:flex-start;gap:.6rem;padding:.38rem .6rem;border-radius:8px;text-decoration:none;color:#000;transition:background .15s}
.tn-dd-item:hover{background:#f3f4f6}
.tn-ic{width:16px;height:16px;flex:0 0 16px;opacity:.7;margin-top:2px;color:#000}
.tn-dd-title{display:block;font-size:.84rem;font-weight:500;color:#000;line-height:1.25}
.tn-dd-desc{display:block;font-size:.72rem;color:#666;line-height:1.3;margin-top:1px}
.tn-strip{width:100%;margin:0;background:transparent;border-top:1px solid #eef0f3}
.tn-strip-in{display:flex;flex-wrap:wrap;gap:.2rem 1.25rem;padding:.55rem 1.25rem .65rem}
.tn-strip-label,.tn-strip-item span{display:none}
.tn-strip-item{text-decoration:none}
.tn-strip-item b{font-size:.8rem;font-weight:600;color:#007a43}
.tn-strip-item:hover b{color:#00b565;text-decoration:underline}
.tn-coins{display:flex;flex-direction:column;gap:.15rem;margin-bottom:.5rem}
.tn-coin{display:flex;align-items:center;gap:.6rem;padding:.3rem .6rem;text-decoration:none;color:#000;font-size:.85rem}
.tn-coin img{width:22px;height:22px;border-radius:50%}
html[data-theme="dark"] .tn-mega{background:#0d0d14;border-color:#1f1f33;box-shadow:0 18px 50px -12px rgba(0,0,0,.8)}
html[data-theme="dark"] .tn-dd-item,html[data-theme="dark"] .tn-dd-title,html[data-theme="dark"] .tn-ic,html[data-theme="dark"] .tn-coin{color:#fff}
html[data-theme="dark"] .tn-dd-item:hover{background:#16161f}
html[data-theme="dark"] .tn-dd-desc{color:#888}
html[data-theme="dark"] .tn-h{color:#00d9a3}
html[data-theme="dark"] .tn-strip{border-top-color:#1f1f33}
html[data-theme="dark"] .tn-strip-item b{color:#00d9a3}
.side-dd{grid-column:1/-1;border:1px solid var(--line);border-radius:9px}
.side-dd summary{padding:9px 12px;font-size:14px;font-weight:500;cursor:pointer;list-style:none;text-align:center}
.side-dd summary::-webkit-details-marker{display:none}
.side-dd a{display:block;padding:7px 14px;font-size:13.5px;color:var(--dim);text-decoration:none}
.side-dd[open]{padding-bottom:6px}
@media (max-width:1180px){.top-nav>a,.top-nav .tn-link{padding:8px 8px}.acct-in{display:none}}
@media (max-width:1023px){.top-nav{display:none}
  .side-links{display:grid;grid-template-columns:1fr 1fr;gap:6px;margin:0 0 14px}
  .side-links>a{padding:9px 12px;border:1px solid var(--line);border-radius:9px;color:var(--text);text-decoration:none;font-size:14px;font-weight:500;text-align:center}}

/* scrollbars: thin and quiet, with a rounded thumb that shows clearly while the menu is in use */
/* Firefox has only the standard properties; Chrome and Safari ignore their own ::-webkit-scrollbar styles when the
   standard ones are set, so those go to Firefox alone */
@supports not selector(::-webkit-scrollbar){
  html{scrollbar-width:thin;scrollbar-color:var(--line2) transparent}
  .side-in,.toc,.sm-res{scrollbar-width:thin;scrollbar-color:var(--line) transparent}
  .side-in:hover,.toc:hover,.sm-res:hover{scrollbar-color:var(--faint) transparent}
}
::-webkit-scrollbar{width:10px;height:10px}
::-webkit-scrollbar-button{display:none;width:0;height:0}
::-webkit-scrollbar-track{background:transparent}
::-webkit-scrollbar-thumb{background:var(--line2);border-radius:10px;border:3px solid transparent;background-clip:padding-box}
::-webkit-scrollbar-thumb:hover{background:var(--faint);background-clip:padding-box;border:3px solid transparent}
::-webkit-scrollbar-corner{background:transparent}
.side-in::-webkit-scrollbar,.toc::-webkit-scrollbar,.sm-res::-webkit-scrollbar{width:8px}
.side-in::-webkit-scrollbar-thumb,.toc::-webkit-scrollbar-thumb,.sm-res::-webkit-scrollbar-thumb{background:var(--line);border:2px solid transparent;background-clip:padding-box}
.side-in:hover::-webkit-scrollbar-thumb,.toc:hover::-webkit-scrollbar-thumb,.sm-res:hover::-webkit-scrollbar-thumb{background:var(--faint);background-clip:padding-box}
.side-in::-webkit-scrollbar-thumb:hover,.toc::-webkit-scrollbar-thumb:hover{background:var(--accent)!important;background-clip:padding-box!important}
.prose pre::-webkit-scrollbar-thumb{background:rgba(255,255,255,.18);background-clip:padding-box}
.brand span,.cta,.acct-me{white-space:nowrap}
@media (max-width:420px){.brand{font-size:16px}.top-in{gap:10px;padding:0 14px}.top-r{gap:6px}.top-r .icon-btn{width:34px;height:34px}}