:root {
  --bg: #081018;
  --panel: #101d2d;
  --panel-2: #142338;
  --line: #243750;
  --text: #e7f0fb;
  --muted: #9db3c8;
  --blue: #78d8ff;
  --gold: #f6d27c;
  --cyan: #8ef4df;
  --red: #ff8b7a;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "Segoe UI", "Hiragino Sans", "Yu Gothic UI", sans-serif;
  background: radial-gradient(circle at top, #142741 0%, var(--bg) 45%);
  color: var(--text);
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
code { background: rgba(255,255,255,0.08); padding: 2px 6px; border-radius: 6px; }
.shell { display: grid; grid-template-columns: 320px 1fr; min-height: 100vh; }
.sidebar {
  position: sticky; top: 0; align-self: start; height: 100vh; overflow: auto;
  padding: 20px; border-right: 1px solid var(--line);
  background: rgba(9, 17, 28, 0.92); backdrop-filter: blur(12px);
}
.brand { display: flex; gap: 14px; align-items: center; margin-bottom: 18px; }
.brand-logo {
  width: 46px; height: 46px; display: inline-grid; place-items: center; border-radius: 14px;
  background: linear-gradient(135deg, #6dd7ff, #2b507f); color: white; font-weight: 800;
  box-shadow: 0 10px 20px rgba(0,0,0,.25);
}
.brand small, .nav-link small, .summary, .eyebrow, .gallery-meta { color: var(--muted); }
.search { display: grid; grid-template-columns: 1fr auto; gap: 8px; margin-bottom: 18px; }
.search input, .search button {
  border: 1px solid var(--line); border-radius: 12px; padding: 11px 12px; font: inherit;
}
.search input { background: #091320; color: var(--text); }
.search button { background: linear-gradient(135deg, #25466a, #15283d); color: #fff; cursor: pointer; }
.nav-group { margin-top: 18px; }
.nav-group h2 { font-size: 12px; text-transform: uppercase; letter-spacing: .12em; color: var(--muted); margin: 0 0 10px; }
.nav-links { display: grid; gap: 8px; }
.nav-link {
  padding: 10px 12px; border: 1px solid var(--line); border-radius: 14px; background: rgba(255,255,255,0.02);
}
.nav-link.active { border-color: #74cfff; background: rgba(116,207,255,0.1); box-shadow: inset 0 0 0 1px rgba(116,207,255,.18); }
.nav-main { display: block; font-weight: 700; margin-bottom: 4px; }
.main { padding: 28px; }
.hero {
  display: grid; grid-template-columns: 1.35fr minmax(220px, 360px); gap: 18px; align-items: stretch; margin-bottom: 24px;
}
.hero, .panel, .sidebar-card {
  background: linear-gradient(180deg, rgba(19,32,49,.96), rgba(15,26,40,.96));
  border: 1px solid var(--line); border-radius: 24px; box-shadow: 0 18px 40px rgba(0,0,0,.18);
}
.hero { padding: 22px; }
.hero h1 { margin: 6px 0 10px; font-size: clamp(28px, 4vw, 42px); }
.hero-figure { margin: 0; border-radius: 18px; overflow: hidden; border: 1px solid rgba(255,255,255,0.08); background: #0b1524; }
.hero-figure img { width: 100%; height: 100%; object-fit: cover; }
.tag-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.tag { padding: 6px 10px; border-radius: 999px; background: rgba(255,255,255,0.06); border: 1px solid rgba(255,255,255,0.08); font-size: 12px; }
.section-space { margin-bottom: 22px; }
.chapter-grid, .mini-grid { display: grid; gap: 16px; }
.chapter-grid { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.chapter-card, .mini-card, .gallery-card {
  border: 1px solid var(--line); border-radius: 18px; padding: 16px; background: var(--panel-2);
}
.chapter-card strong, .mini-card strong, .gallery-body strong { display: block; margin: 6px 0 8px; font-size: 18px; }
.chapter-kicker { display: inline-block; font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: .12em; }
.accent-blue { box-shadow: inset 0 0 0 1px rgba(120,216,255,.22); }
.accent-gold { box-shadow: inset 0 0 0 1px rgba(246,210,124,.22); }
.accent-cyan { box-shadow: inset 0 0 0 1px rgba(142,244,223,.22); }
.accent-red { box-shadow: inset 0 0 0 1px rgba(255,139,122,.22); }
.content-grid { display: grid; grid-template-columns: minmax(0, 1fr) 280px; gap: 18px; }
.panel { padding: 20px; margin-bottom: 18px; }
.panel-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 14px; }
.panel-header h2 { margin: 0; font-size: 22px; }
.content-image { margin: 0 0 14px; overflow: hidden; border-radius: 18px; border: 1px solid rgba(255,255,255,.08); }
.content-image img { width: 100%; background: #0d1827; }
.bullet-list, .step-list { padding-left: 22px; display: grid; gap: 10px; }
.table-wrap { overflow: auto; }
table { width: 100%; border-collapse: collapse; }
th, td { padding: 12px; border-bottom: 1px solid rgba(255,255,255,0.08); text-align: left; vertical-align: top; }
th { color: var(--muted); font-weight: 700; }
.qa-list { display: grid; gap: 12px; }
.qa-item { border: 1px solid rgba(255,255,255,0.08); border-radius: 16px; padding: 14px; background: rgba(255,255,255,0.03); }
.gallery-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; }
.gallery-card { padding: 0; overflow: hidden; }
.gallery-card img { width: 100%; aspect-ratio: 1 / 1; object-fit: cover; background: #0c1521; }
.gallery-body { padding: 14px; }
.gallery-meta { font-size: 12px; text-transform: uppercase; letter-spacing: .08em; margin-bottom: 4px; }
.sidebar-card { padding: 16px; }
.sidebar-card.compact { margin-top: 18px; }
.toc-wrap { position: sticky; top: 20px; align-self: start; }
.toc-links { display: grid; gap: 8px; }
.toc-link {
  padding: 10px 12px; border-radius: 12px; background: rgba(255,255,255,0.04); border: 1px solid rgba(255,255,255,0.06);
}
.toc-link.current { background: rgba(116,207,255,0.10); border-color: rgba(116,207,255,.22); }
.pager { display: flex; justify-content: space-between; gap: 14px; margin-top: 12px; }
.pager a, .pager span { padding: 10px 14px; border: 1px solid var(--line); border-radius: 12px; background: rgba(255,255,255,0.03); }
@media (max-width: 1200px) {
  .content-grid { grid-template-columns: 1fr; }
  .toc-wrap { position: static; }
}
@media (max-width: 960px) {
  .shell { grid-template-columns: 1fr; }
  .sidebar { position: static; height: auto; border-right: 0; border-bottom: 1px solid var(--line); }
  .main { padding: 18px; }
  .hero { grid-template-columns: 1fr; }
}