/* 2Origin.org — 本象协议 / 2Origin Protocol
   From Shadow to Origin. 零依赖，纯静态。
   Design tokens: dark hero = shadow, light body = origin. */

:root {
  --ink: #111113;
  --ink-soft: #2a2a2f;
  --paper: #faf9f6;
  --paper-2: #f1efe9;
  --line: #e3e0d7;
  --gold: #c9a227;
  --gold-deep: #9a7c1c;
  --amber-glow: rgba(201, 162, 39, 0.35);
  --text: #232328;
  --text-soft: #5c5c66;
  --text-faint: #8a8a94;
  --serif: "Songti SC", "STSong", "Noto Serif SC", Georgia, "Times New Roman", serif;
  --sans: "Inter", "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, -apple-system, sans-serif;
  --mono: "JetBrains Mono", "SFMono-Regular", "Cascadia Code", Consolas, monospace;
  --radius: 14px;
  --shadow-card: 0 1px 2px rgba(17,17,19,.04), 0 8px 24px rgba(17,17,19,.05);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--sans);
  color: var(--text);
  background: var(--paper);
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

/* ---------- Nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(250,249,246,.86);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  max-width: 1080px; margin: 0 auto; padding: 14px 22px;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 700; color: var(--ink); text-decoration: none; font-size: 17px; letter-spacing: .2px;
}
.brand-mark {
  width: 30px; height: 30px; border-radius: 8px; flex-shrink: 0;
  background: linear-gradient(135deg, #111113 0%, #111113 48%, var(--gold) 100%);
  position: relative;
}
.brand-mark::after {
  content: ""; position: absolute; inset: 5px; border-radius: 5px;
  background: radial-gradient(circle at 80% 20%, var(--amber-glow), transparent 60%);
  opacity: .9;
}
.brand .zh-name { font-weight: 500; color: var(--text-soft); font-size: 15px; }
.nav-links { display: flex; align-items: center; gap: 22px; font-size: 14.5px; }
.nav-links a { color: var(--text-soft); text-decoration: none; transition: color .15s; }
.nav-links a:hover { color: var(--ink); }
.nav-links .gh { font-weight: 600; color: var(--ink); }
.nav-links .gh:hover { color: var(--gold-deep); }
.lang-switch {
  font-size: 13px; padding: 5px 12px; border: 1px solid var(--line);
  border-radius: 999px; color: var(--text-soft); text-decoration: none; transition: all .15s;
  white-space: nowrap;
}
.lang-switch:hover { border-color: var(--gold); color: var(--ink); }

/* ---------- Hero ---------- */
.hero {
  background:
    radial-gradient(ellipse 80% 60% at 70% -10%, var(--amber-glow), transparent 60%),
    radial-gradient(ellipse 50% 40% at 15% 110%, rgba(201,162,39,.12), transparent 60%),
    var(--ink);
  color: var(--paper);
  padding: 88px 22px 72px;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: ""; position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.028) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.028) 1px, transparent 1px);
  background-size: 44px 44px;
  pointer-events: none;
}
.hero-inner { max-width: 1080px; margin: 0 auto; position: relative; }
.eyebrow {
  font-family: var(--mono); font-size: 12.5px; letter-spacing: 2.5px;
  text-transform: uppercase; color: var(--gold); margin-bottom: 20px;
}
.hero h1 {
  font-family: var(--serif);
  font-size: clamp(38px, 6.4vw, 68px);
  line-height: 1.12; font-weight: 700; letter-spacing: .5px;
  max-width: 17em;
}
.hero h1 .grad {
  background: linear-gradient(100deg, var(--paper) 30%, var(--gold) 90%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero .sub {
  margin-top: 26px; font-size: clamp(17px, 2.2vw, 21px); line-height: 1.7;
  color: rgba(250,249,246,.82); max-width: 34em;
}
.hero .sub em { font-style: normal; color: var(--gold); }
.hero-cta { margin-top: 38px; display: flex; gap: 14px; flex-wrap: wrap; }
.btn {
  display: inline-block; padding: 12px 24px; border-radius: 10px;
  font-weight: 600; font-size: 15px; text-decoration: none; transition: all .15s;
}
.btn-primary { background: var(--gold); color: var(--ink); }
.btn-primary:hover { background: #d8b63a; transform: translateY(-1px); }
.btn-ghost { border: 1px solid rgba(250,249,246,.35); color: var(--paper); }
.btn-ghost:hover { border-color: var(--gold); color: var(--gold); }
.hero-metrics {
  margin-top: 56px; display: grid; grid-template-columns: repeat(4, 1fr);
  gap: 1px; background: rgba(250,249,246,.1); border: 1px solid rgba(250,249,246,.1);
  border-radius: var(--radius); overflow: hidden;
}
.metric { background: rgba(17,17,19,.5); padding: 18px 20px; }
.metric .num { font-size: 26px; font-weight: 700; font-family: var(--mono); color: var(--paper); }
.metric .num em { font-style: normal; color: var(--gold); }
.metric .lbl { font-size: 12.5px; color: rgba(250,249,246,.6); margin-top: 3px; }

/* ---------- Sections ---------- */
.section { max-width: 1080px; margin: 0 auto; padding: 72px 22px; }
.section.tight { padding-top: 48px; padding-bottom: 48px; }
.sec-kicker { font-family: var(--mono); font-size: 12px; letter-spacing: 2px; text-transform: uppercase; color: var(--gold-deep); margin-bottom: 12px; }
.sec-title { font-family: var(--serif); font-size: clamp(26px, 3.6vw, 38px); font-weight: 700; line-height: 1.25; color: var(--ink); }
.sec-title .zh { display: block; font-size: .55em; color: var(--text-soft); font-weight: 500; margin-top: 8px; }
.sec-lead { margin-top: 16px; font-size: 17.5px; color: var(--text-soft); max-width: 44em; line-height: 1.8; }

/* Problem cards */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 40px; }
.card {
  background: var(--paper-2); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 24px; box-shadow: var(--shadow-card);
}
.card .tag { font-family: var(--mono); font-size: 11.5px; letter-spacing: 1.5px; text-transform: uppercase; color: var(--gold-deep); }
.card h3 { margin-top: 10px; font-size: 19px; color: var(--ink); }
.card p { margin-top: 10px; font-size: 14.5px; color: var(--text-soft); line-height: 1.7; }

/* The origin statement */
.origin-block {
  background: var(--ink); color: var(--paper); border-radius: var(--radius);
  padding: 40px 36px; margin-top: 44px; position: relative; overflow: hidden;
}
.origin-block::after {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(ellipse 60% 50% at 80% 120%, var(--amber-glow), transparent 70%);
  pointer-events: none;
}
.origin-block .quote {
  font-family: var(--serif); font-size: clamp(20px, 2.6vw, 27px); line-height: 1.6; font-weight: 600;
  position: relative; z-index: 1;
}
.origin-block .quote em { font-style: normal; color: var(--gold); }
.origin-block .subnote { margin-top: 14px; font-size: 14px; color: rgba(250,249,246,.65); position: relative; z-index: 1; }

/* Pipeline diagram */
.pipeline { margin-top: 44px; font-family: var(--mono); font-size: 13px; line-height: 1.9; color: var(--text-soft); }
.pipeline .flow {
  background: var(--paper-2); border: 1px solid var(--line); border-radius: 10px;
  padding: 18px 22px; overflow-x: auto; white-space: pre; color: var(--text);
}

/* Data tables */
.data-table { margin-top: 34px; width: 100%; border-collapse: collapse; font-size: 14.5px; }
.data-table th, .data-table td { text-align: left; padding: 11px 14px; border-bottom: 1px solid var(--line); }
.data-table thead th { font-family: var(--mono); font-size: 11.5px; letter-spacing: 1px; text-transform: uppercase; color: var(--text-faint); }
.data-table td { color: var(--text); }
.data-table .hl { color: var(--gold-deep); font-weight: 700; }
.data-table .dim { color: var(--text-faint); }
.data-table caption { caption-side: top; text-align: left; font-size: 13px; color: var(--text-soft); padding-bottom: 10px; }
.note { margin-top: 14px; font-size: 13.5px; color: var(--text-soft); }
.note.strong { color: var(--ink); font-weight: 600; }
blockquote.pull {
  margin-top: 30px; padding: 20px 24px; border-left: 3px solid var(--gold);
  background: var(--paper-2); border-radius: 0 10px 10px 0; font-family: var(--serif);
  font-size: 18px; line-height: 1.7; color: var(--ink);
}
blockquote.pull .who { display: block; margin-top: 8px; font-family: var(--sans); font-size: 13px; color: var(--text-faint); }

/* Dialect chips */
.chips { margin-top: 40px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.chip {
  background: var(--paper-2); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px 20px; text-decoration: none; color: inherit; transition: all .15s;
}
.chip:hover { border-color: var(--gold); transform: translateY(-2px); box-shadow: var(--shadow-card); }
.chip .en { font-family: var(--mono); font-size: 11px; letter-spacing: 1.5px; text-transform: uppercase; color: var(--gold-deep); }
.chip h3 { margin-top: 8px; font-size: 18px; color: var(--ink); }
.chip p { margin-top: 8px; font-size: 13.5px; color: var(--text-soft); line-height: 1.65; }

/* Two column */
.two-col { display: grid; grid-template-columns: 1.2fr 1fr; gap: 40px; align-items: start; margin-top: 36px; }

/* ---------- Honesty panel ---------- */
.honesty {
  border: 1px solid var(--gold); background: #fdfaf0; border-radius: var(--radius);
  padding: 28px 30px; margin-top: 44px;
}
.honesty h3 { font-family: var(--serif); font-size: 20px; color: var(--ink); display: flex; align-items: center; gap: 8px; }
.honesty ul { margin-top: 14px; padding-left: 20px; font-size: 14.5px; color: var(--text-soft); line-height: 1.8; }
.honesty li::marker { color: var(--gold); }

/* ---------- Footer ---------- */
.footer {
  border-top: 1px solid var(--line); background: var(--paper-2); margin-top: 60px;
}
.footer-inner { max-width: 1080px; margin: 0 auto; padding: 40px 22px; display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 30px; }
.footer .brand-line { font-weight: 700; color: var(--ink); }
.footer .brand-line .zh { font-weight: 500; color: var(--text-soft); font-size: 14px; }
.footer p { margin-top: 10px; font-size: 13.5px; color: var(--text-soft); line-height: 1.7; }
.footer h4 { font-size: 13px; letter-spacing: 1px; text-transform: uppercase; color: var(--text-faint); margin-bottom: 10px; }
.footer a { display: block; color: var(--text-soft); text-decoration: none; font-size: 14px; padding: 3px 0; }
.footer a:hover { color: var(--gold-deep); }
.footer-bottom { border-top: 1px solid var(--line); }
.footer-bottom .in { max-width: 1080px; margin: 0 auto; padding: 16px 22px; font-size: 12.5px; color: var(--text-faint); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }

/* ---------- Page hero (subpages) ---------- */
.page-hero { background: var(--ink); color: var(--paper); padding: 64px 22px 52px; position: relative; overflow: hidden; }
.page-hero::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(ellipse 70% 55% at 75% -10%, var(--amber-glow), transparent 60%);
  pointer-events: none;
}
.page-hero-inner { max-width: 1080px; margin: 0 auto; position: relative; }
.page-hero h1 { font-family: var(--serif); font-size: clamp(30px, 4.4vw, 48px); font-weight: 700; line-height: 1.2; }
.page-hero .sub { margin-top: 16px; font-size: 17px; color: rgba(250,249,246,.78); max-width: 40em; line-height: 1.7; }
.breadcrumb { font-family: var(--mono); font-size: 12px; letter-spacing: 2px; text-transform: uppercase; color: var(--gold); margin-bottom: 16px; }
.breadcrumb a { color: var(--gold); text-decoration: none; }

/* Prose for long content */
.prose { max-width: 760px; }
.prose h2 { font-family: var(--serif); font-size: 26px; color: var(--ink); margin-top: 48px; margin-bottom: 14px; }
.prose h3 { font-size: 19px; color: var(--ink); margin-top: 32px; margin-bottom: 10px; }
.prose p { margin-bottom: 16px; color: var(--text); font-size: 16px; line-height: 1.85; }
.prose strong { color: var(--ink); }
.prose ul, .prose ol { margin: 0 0 16px 22px; color: var(--text); line-height: 1.85; }
.prose li { margin-bottom: 6px; }
.prose blockquote { border-left: 3px solid var(--gold); padding: 4px 0 4px 20px; margin: 22px 0; color: var(--text-soft); font-family: var(--serif); font-size: 17px; line-height: 1.7; }
.prose code { font-family: var(--mono); font-size: 13.5px; background: var(--paper-2); border: 1px solid var(--line); border-radius: 5px; padding: 1px 6px; }
.prose pre { background: var(--ink); color: var(--paper); border-radius: 10px; padding: 18px 20px; overflow-x: auto; margin: 20px 0; font-family: var(--mono); font-size: 13px; line-height: 1.7; }
.prose pre code { background: none; border: none; color: inherit; padding: 0; }

/* Timeline / milestones */
.milestones { margin-top: 40px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.milestone { border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; background: var(--paper); }
.milestone .dist { font-family: var(--mono); font-size: 13px; color: var(--gold-deep); }
.milestone h3 { font-size: 17px; color: var(--ink); margin-top: 6px; }
.milestone p { font-size: 13px; color: var(--text-soft); margin-top: 8px; }

/* ---------- Responsive ---------- */
@media (max-width: 820px) {
  .hero-metrics { grid-template-columns: repeat(2, 1fr); }
  .grid-3, .chips, .milestones { grid-template-columns: 1fr; }
  .two-col { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; }
  .nav-links .hide-sm { display: none; }
  .hero { padding: 64px 20px 52px; }
  .section { padding: 56px 20px; }
  .origin-block { padding: 30px 24px; }
  .data-table { font-size: 13px; }
  .data-table th, .data-table td { padding: 9px 10px; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #17171a; --paper-2: #1e1e23; --line: #2c2c33;
    --text: #e8e6e1; --text-soft: #b5b3ad; --text-faint: #7a7a84;
    --ink: #eceaf0; --ink-soft: #c9c7d0;
    --shadow-card: 0 1px 2px rgba(0,0,0,.4), 0 8px 24px rgba(0,0,0,.3);
  }
  body { background: var(--paper); }
  .nav { background: rgba(23,23,26,.85); border-bottom-color: var(--line); }
  .brand { color: var(--ink); }
  .card, .chip, .honesty, .data-table td { background: var(--paper-2); }
  .honesty { background: #26241c; }
  .footer { background: var(--paper-2); }
  .origin-block { background: #0e0e10; }
  .metric { background: rgba(23,23,26,.6); }
}