html{scroll-behavior:smooth;scroll-padding-top:84px}
body{font-size:16px;line-height:1.72}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline;text-underline-offset:3px}
p code,li code,td code,.takeaway code,h2 code{font-size:.86em;background:var(--code-bg);color:var(--code-text);padding:.12em .38em;border-radius:5px;border:1px solid color-mix(in srgb,var(--border) 70%,transparent);white-space:nowrap}
strong{font-weight:650;color:var(--text)}
.wrap{max-width:1480px;margin:0 auto;padding:0 32px}

/* top bar */
.topbar{position:sticky;top:0;z-index:50;background:color-mix(in srgb,var(--bg) 78%,transparent);backdrop-filter:saturate(1.6) blur(14px);-webkit-backdrop-filter:saturate(1.6) blur(14px);border-bottom:1px solid var(--border)}
.topbar .wrap{display:flex;align-items:center;gap:20px;height:60px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;color:var(--text);letter-spacing:-.01em;font-size:15px;white-space:nowrap}
.brand:hover{text-decoration:none}
.logo{width:28px;height:28px;border-radius:8px;display:grid;place-items:center;color:#fff;font:700 17px/1 "Inter",serif;background:conic-gradient(from 200deg,#8b5cf6,#3b82f6,#10b981,#f59e0b,#ec4899,#8b5cf6);box-shadow:inset 0 0 0 1px rgba(255,255,255,.25)}
.logo span{display:grid;place-items:center;width:22px;height:22px;border-radius:6px;background:#0b0d12}
.brand small{font:500 12px var(--mono);color:var(--text-3);padding:3px 7px;border:1px solid var(--border);border-radius:6px}
.topnav{display:flex;gap:4px;margin-left:8px}
.topnav a{color:var(--text-2);font-size:14px;font-weight:500;padding:6px 10px;border-radius:8px}
.topnav a:hover{color:var(--text);background:var(--bg-2);text-decoration:none}
.spacer{flex:1}
.tools{display:flex;align-items:center;gap:8px}
.seg{display:inline-flex;padding:3px;border:1px solid var(--border);border-radius:10px;background:var(--bg-2)}
.seg button{border:0;background:transparent;padding:4px 10px;font-size:13px;font-weight:600;border-radius:7px;cursor:pointer;color:var(--text-3)}
.seg button[aria-pressed=true]{background:var(--surface);color:var(--text);box-shadow:0 1px 2px rgba(0,0,0,.08),0 0 0 1px var(--border)}
.iconbtn{width:36px;height:36px;display:grid;place-items:center;border:1px solid var(--border);background:var(--surface);border-radius:10px;cursor:pointer;color:var(--text-2)}
.iconbtn:hover{color:var(--text);border-color:var(--border-2)}
.iconbtn svg{width:18px;height:18px}
.btn{display:inline-flex;align-items:center;gap:8px;height:42px;padding:0 18px;border-radius:11px;font-size:15px;font-weight:600;border:1px solid var(--border-2);color:var(--text);background:var(--surface);white-space:nowrap}
.btn:hover{text-decoration:none;border-color:var(--text-3)}
.btn.primary{background:var(--text);color:var(--bg);border-color:var(--text)}
.btn.primary:hover{opacity:.9}
.btn.sm{height:34px;padding:0 12px;font-size:13.5px;border-radius:9px}
.progress{position:absolute;left:0;bottom:-1px;height:2px;width:0;background:linear-gradient(90deg,var(--coding),var(--agent),var(--ai));transition:width .1s linear}
.only-mobile{display:none}

/* hero */
.hero{position:relative;overflow:hidden;border-bottom:1px solid var(--border)}
.hero::before{content:"";position:absolute;inset:-40% -10% auto -10%;height:900px;pointer-events:none;
  background:radial-gradient(600px 340px at 18% 30%,color-mix(in srgb,var(--coding) 16%,transparent),transparent 70%),
  radial-gradient(520px 320px at 62% 10%,color-mix(in srgb,var(--agent) 13%,transparent),transparent 70%),
  radial-gradient(480px 300px at 88% 46%,color-mix(in srgb,var(--ai) 12%,transparent),transparent 70%)}
.hero::after{content:"";position:absolute;inset:0;pointer-events:none;opacity:.5;
  background-image:linear-gradient(var(--border) 1px,transparent 1px),linear-gradient(90deg,var(--border) 1px,transparent 1px);background-size:56px 56px;
  -webkit-mask-image:radial-gradient(ellipse 70% 60% at 50% 0%,#000 30%,transparent 75%);mask-image:radial-gradient(ellipse 70% 60% at 50% 0%,#000 30%,transparent 75%)}
.hero .wrap{position:relative;z-index:1;padding-top:76px;padding-bottom:64px;display:grid;grid-template-columns:minmax(0,1.15fr) minmax(0,.85fr);gap:56px;align-items:center}
.eyebrow{display:inline-flex;align-items:center;gap:10px;font-size:13px;font-weight:500;color:var(--text-2);padding:5px 12px 5px 6px;border:1px solid var(--border);border-radius:999px;background:color-mix(in srgb,var(--surface) 80%,transparent)}
.eyebrow b{font:600 11.5px var(--mono);color:var(--accent);background:var(--accent-soft);padding:3px 8px;border-radius:999px}
.hero h1{font-size:clamp(38px,5.4vw,64px);line-height:1.06;letter-spacing:-.035em;font-weight:750;margin:22px 0 18px}
.hero h1 .grad{background:linear-gradient(100deg,var(--coding) 0%,var(--agent) 45%,var(--ai) 90%);-webkit-background-clip:text;background-clip:text;color:transparent}
.lead{font-size:clamp(17px,1.6vw,19.5px);line-height:1.65;color:var(--text-2);max-width:620px;margin:0 0 30px}
.cta{display:flex;gap:12px;flex-wrap:wrap}
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--border);border:1px solid var(--border);border-radius:16px;overflow:hidden;margin-top:44px;box-shadow:var(--shadow)}
.stat{background:var(--surface);padding:18px 18px 16px}
.stat .n{font-size:28px;font-weight:700;letter-spacing:-.03em;font-variant-numeric:tabular-nums;line-height:1.1}
.stat .k{font-size:13px;color:var(--text-3);margin-top:6px;line-height:1.35}
.stack{position:relative;display:grid;gap:10px;padding:22px;border:1px solid var(--border);border-radius:20px;background:color-mix(in srgb,var(--surface) 86%,transparent);box-shadow:var(--shadow)}
.stack-h{display:flex;justify-content:space-between;align-items:center;font-size:12px;color:var(--text-3);font-weight:600;letter-spacing:.08em;text-transform:uppercase;margin-bottom:2px}
.tier{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:14px 16px;border-radius:12px;background:var(--l-bg);border:1px solid color-mix(in srgb,var(--l) 40%,transparent);color:var(--l-fg);transition:transform .2s ease}
.tier:hover{transform:translateX(4px);text-decoration:none}
.tier b{font-size:15px;font-weight:650;letter-spacing:-.01em}
.tier span{font:500 12px var(--mono);opacity:.8;text-align:right}
.tier-row{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.tier-row .tier{flex-direction:column;align-items:flex-start;gap:4px}
.tier-row .tier span{text-align:left}
:root[data-theme=dark] .th-moon,:root:not([data-theme=dark]) .th-sun{display:none}
.stack-arrow{display:flex;justify-content:center;color:var(--text-3);font-size:12px;margin:-4px 0}

/* layout */
.layout{display:grid;grid-template-columns:236px minmax(0,1fr);gap:48px;align-items:start}
.toc{position:sticky;top:60px;max-height:calc(100vh - 60px);overflow:auto;padding:32px 4px 40px 0;scrollbar-width:thin}
.toc-g{font-size:11.5px;font-weight:650;letter-spacing:.09em;text-transform:uppercase;color:var(--text-3);margin:20px 0 6px 12px}
.toc-g:first-child{margin-top:0}
.toc a{position:relative;display:flex;gap:10px;align-items:baseline;padding:6px 12px;border-radius:8px;color:var(--text-2);font-size:14px;line-height:1.4}
.toc a:hover{background:var(--bg-2);color:var(--text);text-decoration:none}
.toc a .no{font:500 11.5px var(--mono);color:var(--text-3);min-width:18px}
.toc a.active{color:var(--text);background:var(--bg-2);font-weight:600}
.toc a.active::before{content:"";position:absolute;left:0;top:7px;bottom:7px;width:2.5px;border-radius:2px;background:var(--l,var(--accent))}
.toc a .dot{width:6px;height:6px;border-radius:50%;background:var(--l);margin-left:auto;align-self:center;opacity:.9}
.toc-foot{margin:22px 12px 0;padding-top:18px;border-top:1px solid var(--border);display:grid;gap:8px;font-size:13px}
.toc-foot a{padding:0;color:var(--text-2)}
main{min-width:0;padding:40px 0 80px}

/* legend */
.legend{border:1px solid var(--border);border-radius:16px;padding:22px 24px;background:var(--surface-2);margin-bottom:24px}
.legend h2{font-size:15px;margin:0 0 12px;letter-spacing:-.01em}
.legend .chips{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:14px}
.legend ul{margin:0;padding-left:18px;color:var(--text-2);font-size:14px;display:grid;grid-template-columns:1fr 1fr;gap:4px 28px}

/* sections */
.sec{padding:56px 0 28px;border-top:1px solid var(--border)}
.sec:first-of-type{border-top:0}
.sec-meta{display:flex;align-items:center;gap:12px;margin-bottom:12px}
.sec-no{font:600 13px var(--mono);color:var(--text-3)}
.sec h2{font-size:clamp(26px,2.6vw,34px);line-height:1.2;letter-spacing:-.025em;font-weight:720;margin:0 0 14px}
.sec h2 a.anchor{color:var(--text-3);opacity:0;margin-left:10px;font-weight:500;font-size:.7em;transition:opacity .15s}
.sec h2:hover a.anchor{opacity:1}
.takeaway{position:relative;font-size:18.5px;line-height:1.66;color:var(--text);margin:0 0 26px;padding:16px 20px 16px 22px;border-radius:12px;background:linear-gradient(90deg,color-mix(in srgb,var(--l) 10%,transparent),transparent 80%);border:1px solid color-mix(in srgb,var(--l) 20%,var(--border))}
.takeaway::before{content:"";position:absolute;left:0;top:12px;bottom:12px;width:3px;border-radius:3px;background:var(--l)}
.takeaway .tl{display:block;font-size:11.5px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;color:var(--l-fg);opacity:.75;margin-bottom:4px}
:root[data-theme=dark] .takeaway .tl{color:var(--l)}
figure.diagram{margin:0 0 26px;border:1px solid var(--border);border-radius:16px;background:var(--surface);box-shadow:var(--shadow);overflow:hidden}
figure.diagram figcaption{display:flex;align-items:center;gap:10px;padding:10px 12px 10px 18px;border-bottom:1px solid var(--border);font-size:13px;color:var(--text-3);background:var(--surface-2)}
figure.diagram figcaption .cap{flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
figure.diagram figcaption .dir{font:600 11px var(--mono);padding:3px 7px;border-radius:6px;border:1px solid var(--border);color:var(--text-3)}
.diagram-body{position:relative;padding:28px 20px;overflow-x:auto;cursor:zoom-in;-webkit-overflow-scrolling:touch}
.diagram-body .mmd{min-height:120px}
.diagram-body .mmd:not(.is-rendered){display:grid;place-items:center;color:var(--text-3);font-size:13px}
.swipe-hint{display:none;position:sticky;left:0;font-size:12px;color:var(--text-3);padding:0 0 10px}
.diagram-body.scrolls .swipe-hint{display:block}
.grid2{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:18px;margin-bottom:22px}
.grid2>*,.layout>*,.split>*{min-width:0}
.card{border:1px solid var(--border);border-radius:14px;padding:20px 22px 18px;background:var(--surface)}
.card h3,.files h3{display:flex;align-items:center;gap:8px;font-size:12.5px;font-weight:700;letter-spacing:.09em;text-transform:uppercase;color:var(--text-3);margin:0 0 12px}
.card h3 svg,.files h3 svg{width:15px;height:15px;color:var(--l)}
.card ul,.card ol{margin:0;padding:0;list-style:none;display:grid;gap:10px}
.card li{position:relative;padding-left:20px;font-size:15px;line-height:1.68;color:var(--text-2)}
.card ul li::before{content:"";position:absolute;left:3px;top:.72em;width:6px;height:6px;border-radius:2px;background:var(--l);transform:rotate(45deg)}
.card ol{counter-reset:s}
.card ol li{counter-increment:s;padding-left:30px}
.card ol li::before{content:counter(s);position:absolute;left:0;top:.2em;width:20px;height:20px;border-radius:6px;display:grid;place-items:center;font:600 11.5px/1 var(--mono);background:var(--l-bg);color:var(--l-fg);border:1px solid color-mix(in srgb,var(--l) 35%,transparent)}
.files{margin-bottom:8px}
.tbl{border:1px solid var(--border);border-radius:14px;overflow:hidden;overflow-x:auto;background:var(--surface)}
.tbl table{width:100%;border-collapse:collapse;font-size:14px}
.tbl th{font-size:12px;text-align:left;font-weight:600;color:var(--text-3);background:var(--surface-2);padding:9px 16px;border-bottom:1px solid var(--border)}
.tbl td{padding:11px 16px;border-bottom:1px solid var(--border);vertical-align:top;color:var(--text-2)}
.tbl tr:last-child td{border-bottom:0}
.tbl tbody tr:hover td{background:var(--surface-2)}
.tbl a.f{display:inline-flex;align-items:center;gap:6px;font:500 13px var(--mono);color:var(--text);word-break:break-all}
.tbl a.f .dir{color:var(--text-3)}
.tbl a.f .ln{color:var(--accent);font-size:12px}
.tbl a.f:hover{color:var(--accent);text-decoration:none}
.tbl td.sym code{font-size:12.5px;white-space:nowrap}

.split{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:18px;align-items:start;margin-bottom:22px}
.split figure.diagram{margin:0;position:sticky;top:84px}
.split .grid2{grid-template-columns:1fr;margin:0}
@media (max-width:1180px){.split{display:block}.split figure.diagram{position:static;margin-bottom:22px}.split .grid2{grid-template-columns:1fr 1fr;margin-bottom:22px}}
@media (max-width:960px){.split .grid2{grid-template-columns:1fr}}
/* stats */
.bars{display:grid;gap:8px;margin:6px 0 24px}
.bar{display:grid;grid-template-columns:120px 1fr 92px;gap:14px;align-items:center;font-size:13.5px}
.bar .nm{font:500 13px var(--mono);color:var(--text-2);text-align:right}
.bar .tr{height:22px;border-radius:6px;background:var(--bg-2);overflow:hidden;display:flex}
.bar .s{height:100%;background:var(--l);border-radius:6px 0 0 6px}
.bar .t{height:100%;background:color-mix(in srgb,var(--l) 35%,transparent)}
.bar .v{font-variant-numeric:tabular-nums;color:var(--text-2);font-size:13px}
.bars-key{display:flex;gap:18px;font-size:12.5px;color:var(--text-3);margin:0 0 8px 134px}
.bars-key i{display:inline-block;width:10px;height:10px;border-radius:3px;margin-right:6px;vertical-align:-1px;background:var(--text-3)}
.bars-key i.t{opacity:.35}
.tbl td.num,.tbl th.num{text-align:right;font-variant-numeric:tabular-nums}
.tbl tr.tot td{font-weight:650;color:var(--text);background:var(--surface-2)}
.note{font-size:13.5px;color:var(--text-3);margin:0 0 16px}

footer.foot{border-top:1px solid var(--border);padding:28px 0 48px;font-size:13px;color:var(--text-3);display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap}

/* responsive */
@media (max-width:1180px){.hero .wrap{grid-template-columns:1fr;gap:40px}.stack{max-width:620px}.layout{grid-template-columns:220px minmax(0,1fr);gap:36px}}
@media (max-width:960px){
  .wrap{padding:0 20px}
  .layout{grid-template-columns:minmax(0,1fr)}
  .toc{position:fixed;z-index:60;top:60px;left:0;bottom:0;width:min(320px,86vw);max-height:none;background:var(--bg);border-right:1px solid var(--border);padding:20px 12px;transform:translateX(-102%);transition:transform .22s ease;box-shadow:var(--shadow)}
  body.toc-open .toc{transform:none}
  body.toc-open::after{content:"";position:fixed;inset:60px 0 0;background:rgba(0,0,0,.3);z-index:55}
  .only-mobile{display:grid}
  .topnav{display:none}
  .grid2{grid-template-columns:1fr}
  .legend ul{grid-template-columns:1fr}
  .stats{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:560px){
  body{font-size:15.5px}
  .tools .btn.sm .t2,.tools .gh{display:none}
  .tools{gap:6px}
  p code,li code,td code,.takeaway code{white-space:normal;word-break:break-word}
  .brand .t{display:none}
  .hero .wrap{padding-top:44px;padding-bottom:40px}
  .stat .n{font-size:23px}
  .diagram-body{padding:18px 12px}
  .takeaway{font-size:16.5px;padding:14px 14px 14px 18px}
  .card{padding:16px}
  .tbl td,.tbl th{padding:9px 10px}
  .tbl .col-role{display:none}
  .bar{grid-template-columns:86px 1fr 64px;gap:8px}
  .bars-key{margin-left:94px}
  .tier span{display:none}
  .sec{padding-top:40px}
}
@media print{.topbar,.toc,.cta{display:none}.layout{display:block}}

h1,h2,h3,.takeaway,.lead,.sub{text-wrap:balance}
li,p{text-wrap:pretty}