:root{
  --paper:#faf8f3; --paper-soft:#f2eee4; --paper-deep:#ece6d8;
  --ink:#0f0e0c; --ink-mute:#4c4843; --ink-faint:#938d81;
  --vermilion:#b43a2f; --vermilion-bright:#d9594b; --seal:#8c2f2a;
  --line:rgba(15,14,12,.12); --line-soft:rgba(15,14,12,.07);
  --bg:var(--paper); --fg:var(--ink);
  --mono:'Space Mono',ui-monospace,monospace;
  --serif:'Fraunces',Georgia,serif;
  --sans:'Hanken Grotesk',system-ui,sans-serif;
  --maxw:1180px;
}
[data-theme="dark"]{
  --paper:#0e0d0c; --paper-soft:#151311; --paper-deep:#1c1916;
  --ink:#f4efe6; --ink-mute:#aaa295; --ink-faint:#6f685d;
  --vermilion:#e0675a; --vermilion-bright:#ef8576; --seal:#c2554a;
  --line:rgba(244,239,230,.14); --line-soft:rgba(244,239,230,.07);
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  background:var(--bg); color:var(--fg);
  font-family:var(--sans); font-size:17px; line-height:1.6;
  -webkit-font-smoothing:antialiased; overflow-x:hidden;
  transition:background .5s ease,color .5s ease;
}
/* paper grain */
body::before{
  content:""; position:fixed; inset:0; z-index:1; pointer-events:none;
  background-image: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='0.8' numOctaves='2'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.4'/%3E%3C/svg%3E");
  opacity:.035; mix-blend-mode:multiply;
}
[data-theme="dark"] body::before{mix-blend-mode:screen;opacity:.05}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 28px;position:relative;z-index:2}
a{color:inherit;text-decoration:none}
::selection{background:var(--vermilion);color:var(--paper)}

/* ---------- top bar ---------- */
header.bar{position:fixed;top:0;left:0;right:0;z-index:50;
  backdrop-filter:blur(10px);background:color-mix(in srgb,var(--bg) 78%,transparent);
  border-bottom:1px solid var(--line-soft)}
.bar .wrap{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{display:flex;align-items:center;gap:11px;font-family:var(--mono);font-weight:700;letter-spacing:.02em}
.brand svg{width:30px;height:30px;display:block}
.navlinks{display:flex;gap:26px;align-items:center;font-family:var(--mono);font-size:12.5px;letter-spacing:.04em;text-transform:uppercase}
.navlinks a{color:var(--ink-mute);transition:color .2s}
.navlinks a:hover{color:var(--vermilion)}
.tbtn{cursor:pointer;border:1px solid var(--line);background:transparent;color:var(--ink-mute);
  width:34px;height:34px;border-radius:50%;display:grid;place-items:center;font-size:14px;transition:.2s}
.tbtn:hover{border-color:var(--vermilion);color:var(--vermilion)}
@media(max-width:720px){.navlinks a:not(.ghub):not(.lang){display:none}.navlinks{gap:18px}}

/* ---------- shared section ---------- */
section{padding:120px 0;position:relative}
.eyebrow{font-family:var(--mono);font-size:12px;letter-spacing:.28em;text-transform:uppercase;color:var(--vermilion);margin-bottom:22px;display:flex;align-items:center;gap:12px}
.eyebrow::before{content:"";width:26px;height:1px;background:var(--vermilion);display:inline-block}
h2.big{font-family:var(--serif);font-weight:400;font-size:clamp(2.1rem,4.6vw,3.6rem);line-height:1.06;letter-spacing:-.015em;max-width:18ch}
.lead{font-size:clamp(1.05rem,1.5vw,1.28rem);color:var(--ink-mute);max-width:62ch;margin-top:26px;line-height:1.65}
.reveal{transition:opacity .9s cubic-bezier(.2,.7,.2,1),transform .9s cubic-bezier(.2,.7,.2,1)}
html.js .reveal{opacity:0;transform:translateY(26px)}
html.js .reveal.in{opacity:1;transform:none}

/* ---------- hero ---------- */
.hero{padding:150px 0 90px;min-height:100vh;display:flex;flex-direction:column;justify-content:center;position:relative}
.hero .eyebrow{justify-content:flex-start}
.hero .eyebrow,.hero h1,.hero .sub,.hero .cta{position:relative;z-index:2}
.hero h1{font-family:var(--serif);font-weight:300;font-size:clamp(2.6rem,7vw,5.6rem);line-height:1.0;letter-spacing:-.02em;max-width:15ch}
.hero h1 em{font-style:italic;color:var(--vermilion)}
.hero .sub{font-size:clamp(1.1rem,1.7vw,1.4rem);color:var(--ink-mute);max-width:54ch;margin-top:34px;line-height:1.55}
.hero .cta{margin-top:46px;display:flex;gap:16px;flex-wrap:wrap;align-items:center}
.btn{font-family:var(--mono);font-size:13.5px;letter-spacing:.02em;padding:14px 22px;border-radius:2px;border:1px solid var(--ink);background:var(--ink);color:var(--paper);transition:.25s;cursor:pointer}
.btn:hover{background:var(--vermilion);border-color:var(--vermilion);color:#fff;transform:translateY(-2px)}
.btn.ghost{background:transparent;color:var(--fg)}
.btn.ghost:hover{background:transparent;color:var(--vermilion);border-color:var(--vermilion)}
.fluxwrap{position:absolute;right:-30px;top:44%;transform:translateY(-50%);width:min(44vw,540px);opacity:.9;pointer-events:none;z-index:1}
@media(max-width:900px){.fluxwrap{position:relative;right:auto;top:auto;transform:none;width:260px;margin:40px 0 0;opacity:.85}.hero{min-height:auto;padding-top:120px}}
.flux-path{fill:none;stroke:var(--ink);stroke-width:2.4;stroke-linecap:round;stroke-dasharray:1;stroke-dashoffset:1;animation:draw 2.6s ease forwards .3s}
@keyframes draw{to{stroke-dashoffset:0}}
.flux-flow{fill:none;stroke:var(--vermilion);stroke-width:2.4;stroke-linecap:round;stroke-dasharray:14 220;opacity:.0;animation:flow 4s linear 2.6s infinite, fadein .8s ease 2.6s forwards}
@keyframes flow{to{stroke-dashoffset:-234}}
@keyframes fadein{to{opacity:.85}}
.seal{animation:pulse 3.4s ease-in-out 2.4s infinite}
@keyframes pulse{0%,100%{opacity:.85}50%{opacity:1}}

/* ---------- terminal ---------- */
.term{background:#100f0d;border-radius:8px;overflow:hidden;border:1px solid var(--line);
  box-shadow:0 30px 80px -30px rgba(0,0,0,.45);font-family:var(--mono);max-width:680px}
.term .tt{display:flex;align-items:center;gap:8px;padding:13px 16px;border-bottom:1px solid rgba(255,255,255,.08)}
.term .tt i{width:11px;height:11px;border-radius:50%;display:block;background:#3a3733}
.term .tt i.r{background:var(--vermilion)}
.term .tt span{margin-left:10px;color:#6f6a63;font-size:12px}
.term .body{padding:22px 20px;font-size:14px;line-height:1.95;color:#e9e4da;min-height:230px}
.term .ln{white-space:pre-wrap}
.term .p{color:var(--vermilion-bright)}
.term .who{color:#8a857c}
.term .ai{color:#7fb0a8}
.term .ok{color:#9bbf6b}
.term .cur{display:inline-block;width:8px;height:16px;background:var(--vermilion);vertical-align:-3px;animation:blink 1s steps(2) infinite}
@keyframes blink{50%{opacity:0}}

/* ---------- two-col ---------- */
.grid2{display:grid;grid-template-columns:1.05fr .95fr;gap:60px;align-items:start}
@media(max-width:900px){.grid2{grid-template-columns:1fr;gap:40px}}

/* ---------- terminals cards ---------- */
.cards{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;margin-top:54px;background:var(--line);border:1px solid var(--line)}
@media(max-width:860px){.cards{grid-template-columns:repeat(2,1fr)}}
@media(max-width:520px){.cards{grid-template-columns:1fr}}
.card{background:var(--bg);padding:30px 26px;min-height:210px;display:flex;flex-direction:column;transition:background .3s}
.card:hover{background:var(--paper-soft)}
.card .k{font-family:var(--mono);font-size:12px;letter-spacing:.16em;text-transform:uppercase;color:var(--vermilion)}
.card h3{font-family:var(--serif);font-weight:500;font-size:1.45rem;line-height:1.25;margin:14px 0 10px}
.card p{font-size:14.5px;color:var(--ink-mute);line-height:1.6}
.card .tag{margin-top:auto;font-family:var(--mono);font-size:11px;color:var(--ink-faint);letter-spacing:.05em}
.spectrum{display:flex;flex-wrap:wrap;gap:10px;margin-top:36px}
.spectrum span{font-family:var(--mono);font-size:12px;letter-spacing:.03em;padding:7px 14px;border:1px solid var(--line);border-radius:100px;color:var(--ink-mute);transition:.2s}
.spectrum span:hover{border-color:var(--vermilion);color:var(--vermilion)}
.spectrum span.hot{border-color:var(--vermilion);color:var(--vermilion)}
.spectrum-note{font-family:var(--mono);font-size:12.5px;color:var(--ink-faint);margin-top:20px;max-width:60ch;line-height:1.6}

/* ---------- flow ---------- */
.flow{display:flex;align-items:stretch;gap:0;margin-top:50px;border:1px solid var(--line);border-radius:6px;overflow:hidden;flex-wrap:wrap}
.flow .node{flex:1 1 0;min-width:150px;padding:26px 22px;border-right:1px solid var(--line);position:relative}
.flow .node:last-child{border-right:none}
.flow .node .n{font-family:var(--mono);font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--ink-faint)}
.flow .node strong{display:block;font-family:var(--serif);font-weight:500;font-size:1.2rem;margin:9px 0 6px}
.flow .node p{font-size:14px;color:var(--ink-mute);line-height:1.55}
.flow .node.enc strong,.flow .node.dec strong{color:var(--vermilion)}
.flow .pulse{position:absolute;bottom:0;left:0;height:2px;width:100%;background:linear-gradient(90deg,transparent,var(--vermilion),transparent);background-size:50% 100%;animation:slide 3.5s linear infinite}
@keyframes slide{from{background-position:-50% 0}to{background-position:150% 0}}

/* ---------- standards ---------- */
.std{display:grid;grid-template-columns:repeat(3,1fr);gap:26px;margin-top:54px}
@media(max-width:780px){.std{grid-template-columns:1fr}}
.std .s{border-top:2px solid var(--ink);padding-top:22px}
.std .s .num{font-family:var(--mono);font-size:12px;color:var(--vermilion);letter-spacing:.1em}
.std .s h4{font-family:var(--serif);font-weight:500;font-size:1.45rem;line-height:1.25;margin:12px 0}
.std .s p{font-size:14.5px;color:var(--ink-mute);line-height:1.6}
.std .s ul{list-style:none;font-size:14.5px;color:var(--ink-mute);line-height:1.5}
.std .s li{padding:7px 0;border-bottom:1px solid var(--line-soft);display:flex;gap:9px}
.std .s li::before{content:"›";color:var(--vermilion);font-family:var(--mono)}
.std .s li:last-child{border-bottom:none}

/* ---------- family ---------- */
.fam{margin-top:54px;display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
@media(max-width:860px){.fam{grid-template-columns:repeat(2,1fr)}}
.fam .f{border:1px solid var(--line);border-radius:6px;padding:26px 22px;position:relative;transition:.3s;background:var(--bg)}
.fam .f.me{border-color:var(--vermilion);background:color-mix(in srgb,var(--vermilion) 7%,var(--bg))}
.fam .f .role{font-family:var(--mono);font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--ink-faint)}
.fam .f h4{font-family:var(--serif);font-weight:600;font-size:1.45rem;line-height:1.2;margin:10px 0 8px}
.fam .f.me h4{color:var(--vermilion)}
.fam .f p{font-size:14.5px;color:var(--ink-mute);line-height:1.6}
.fam .chain{font-family:var(--mono);font-size:13px;color:var(--ink-faint);text-align:center;margin-top:30px;letter-spacing:.03em}
.fam .chain b{color:var(--vermilion)}

/* ---------- cta ---------- */
.final{text-align:center;padding:140px 0}
.final h2{font-family:var(--serif);font-weight:300;font-size:clamp(2.2rem,5.5vw,4.4rem);line-height:1.05;letter-spacing:-.02em}
.final h2 em{font-style:italic;color:var(--vermilion)}
.codeline{display:inline-flex;align-items:center;gap:12px;margin-top:38px;font-family:var(--mono);font-size:15px;background:#100f0d;color:#faf8f3;padding:16px 24px;border-radius:4px;flex-wrap:wrap;justify-content:center}
.codeline .pp{color:var(--vermilion-bright)}
.codeline .cp{cursor:pointer;color:#8a857c;border:none;background:none;font-family:inherit;font-size:13px}

/* ---------- footer ---------- */
footer{border-top:1px solid var(--line);padding:60px 0 70px;font-size:14px;color:var(--ink-mute)}
footer .wrap{display:flex;justify-content:space-between;gap:30px;flex-wrap:wrap}
footer .mono{font-family:var(--mono);font-size:12px;letter-spacing:.04em;color:var(--ink-faint);line-height:2}
footer a:hover{color:var(--vermilion)}
.lic{font-family:var(--mono);font-size:11.5px;color:var(--ink-faint);margin-top:8px}

/* ---------- responsive (tablet / mobile) ---------- */
@media(max-width:760px){
  body{font-size:16px}
  section{padding:78px 0}
  .wrap{padding:0 22px}
  .hero{padding:116px 0 64px}
  .final{padding:96px 0}
  .cards,.std,.fam,.flow,.spectrum{margin-top:34px}
  .lead{margin-top:22px}
  .eyebrow{margin-bottom:18px}
  footer .wrap{flex-direction:column;gap:18px}
}
@media(max-width:640px){
  .flow{flex-direction:column}
  .flow .node{flex:1 1 auto;min-width:0;border-right:none;border-bottom:1px solid var(--line)}
  .flow .node:last-child{border-bottom:none}
  .fam{grid-template-columns:1fr}
  .hero .cta{gap:12px}
  .btn{padding:13px 20px}
}
@media(max-width:420px){
  .wrap{padding:0 18px}
  .cards{grid-template-columns:1fr}
}