:root {
  --paper: #f4ede0;
  --paper-deep: #ebddc8;
  --card: rgba(255, 250, 243, 0.92);
  --ink: #1d2430;
  --muted: #5b6471;
  --accent: #934b30;
  --accent-dark: #6d301d;
  --gold: #c79a44;
  --line: #dccdb8;
  --water: #7ea5c8;
  --shadow: rgba(77, 56, 34, 0.14);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  font-family: "Noto Serif SC", "Source Han Serif SC", serif;
  background:
    radial-gradient(circle at top left, rgba(199, 154, 68, 0.12), transparent 25%),
    radial-gradient(circle at bottom right, rgba(126, 165, 200, 0.12), transparent 22%),
    linear-gradient(180deg, #fbf6ed 0%, var(--paper) 52%, var(--paper-deep) 100%);
}
a { color: inherit; text-decoration: none; }
.site-shell { display: flex; min-height: 100vh; }
.sidebar {
  width: 320px;
  padding: 28px 22px 36px;
  border-right: 1px solid var(--line);
  background: rgba(248, 241, 229, 0.96);
  position: sticky;
  top: 0;
  align-self: flex-start;
  height: 100vh;
  overflow-y: auto;
  box-shadow: 10px 0 24px rgba(80, 59, 34, 0.06);
}
.sidebar h1 { margin: 0 0 8px; font-size: 34px; }
.sidebar p { margin: 0 0 18px; color: var(--muted); line-height: 1.8; }
.sidebar .group-title { margin: 22px 0 10px; font-size: 13px; letter-spacing: 0.12em; color: var(--accent); }
.sidebar nav a {
  display: block;
  padding: 10px 12px;
  border-radius: 14px;
  margin-bottom: 6px;
  color: var(--ink);
  transition: .18s ease;
}
.sidebar nav a:hover, .sidebar nav a.active {
  background: rgba(147, 75, 48, 0.10);
  color: var(--accent-dark);
  transform: translateX(4px);
}
.sidebar .subnav { padding-left: 14px; }
.sidebar .subnav a { font-size: 14px; color: var(--muted); }
.sidebar-toggle {
  display: none;
  position: fixed;
  left: 14px;
  top: 14px;
  z-index: 40;
  width: 54px;
  height: 54px;
  border: 0;
  border-radius: 50%;
  color: #fff;
  background: linear-gradient(145deg, #a85c3c, #71301e);
  box-shadow: 0 18px 32px rgba(113, 48, 30, 0.32);
}
.content { flex: 1; padding: 32px 34px 72px; }
.page-hero, .card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 28px;
  box-shadow: 0 18px 40px var(--shadow);
}
.page-hero { padding: 30px; margin-bottom: 24px; }
.eyebrow { color: var(--accent); font-size: 13px; letter-spacing: 0.18em; margin-bottom: 12px; }
.hero-grid { display: grid; grid-template-columns: 1.15fr 1fr; gap: 24px; align-items: start; }
.hero-title { margin: 0 0 10px; font-size: 54px; line-height: 1.08; }
.hero-subtitle { margin: 0 0 16px; font-size: 24px; color: var(--accent); }
.hero-text { font-size: 17px; color: var(--muted); line-height: 1.9; margin: 0 0 16px; }
.hero-media img, .hero-media object, .hero-media canvas, .page-image {
  width: 100%;
  display: block;
  border-radius: 22px;
  border: 1px solid var(--line);
  background: #fff;
}
.stat-grid, .grid-2, .grid-3, .grid-4 { display: grid; gap: 18px; }
.stat-grid { grid-template-columns: repeat(4, 1fr); margin-top: 18px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.stat-box, .mini-card, .info-card, .formula-card, .case-detail, .gallery-panel, .section-panel {
  background: rgba(255, 249, 240, 0.92);
  border: 1px solid var(--line);
  border-radius: 22px;
  padding: 20px;
  box-shadow: 0 12px 24px rgba(100, 75, 45, .07);
}
.stat-box span { display: block; color: var(--muted); font-size: 13px; margin-bottom: 6px; }
.stat-box strong { font-size: 30px; color: var(--accent); }
.chip-row { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 14px; }
.chip-row span, .metric-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 12px;
  border-radius: 999px;
  background: #f6ead9;
  border: 1px solid rgba(147, 75, 48, 0.10);
  color: var(--ink);
  font-size: 14px;
}
.section-head { margin: 26px 0 16px; }
.section-head h2 { margin: 0 0 8px; font-size: 34px; }
.section-head p { margin: 0; color: var(--muted); line-height: 1.85; font-size: 17px; }
.section-tag {
  display: inline-block;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(147, 75, 48, 0.08);
  color: var(--accent);
  font-size: 12px;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}
.page-footer {
  margin-top: 30px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}
.lightbox {
  position: fixed;
  inset: 0;
  display: none;
  place-items: center;
  background: rgba(16, 20, 26, 0.82);
  z-index: 90;
  padding: 20px;
}
.lightbox.open { display: grid; }
.lightbox img {
  max-width: min(94vw, 1500px);
  max-height: 88vh;
  border-radius: 18px;
  box-shadow: 0 18px 36px rgba(0, 0, 0, 0.35);
}
.lightbox .caption {
  color: #f7f1e8;
  margin-top: 12px;
  text-align: center;
  font-size: 15px;
}
.lightbox-close {
  position: absolute;
  top: 18px;
  right: 18px;
  width: 48px;
  height: 48px;
  border: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.14);
  color: #fff;
  font-size: 26px;
}
@media (max-width: 980px) {
  .sidebar-toggle { display: block; }
  .sidebar {
    position: fixed;
    left: 0;
    top: 0;
    z-index: 50;
    transform: translateX(-100%);
    transition: transform .24s ease;
  }
  body.nav-open .sidebar { transform: translateX(0); }
  .content { padding: 80px 16px 56px; }
  .hero-grid, .grid-2, .grid-3, .grid-4, .stat-grid { grid-template-columns: 1fr; }
  .hero-title { font-size: 40px; }
}