/* ================================================================
   虾塘 — 深色编辑级设计系统
   ================================================================ */

:root {
  /* Depth layers */
  --bg-root: #070d17;
  --bg-primary: #0b1426;
  --bg-card: #101e37;
  --bg-card-hover: #172844;
  --bg-card-alt: #0f1b30;

  /* Text */
  --text-primary: #e6eef7;
  --text-secondary: #8493ac;
  --text-muted: #566077;

  /* Accent — warm coral (lobster red) */
  --accent: #ff5c3a;
  --accent-soft: #ff7d61;
  --accent-glow: rgba(255, 92, 58, 0.18);

  /* Secondary accents */
  --amber: #f0a548;
  --amber-glow: rgba(240, 165, 72, 0.14);
  --blue: #5b9cf5;
  --blue-glow: rgba(91, 156, 245, 0.12);
  --mint: #3dd6a4;
  --mint-glow: rgba(61, 214, 164, 0.12);
  --violet: #a78bfa;
  --violet-glow: rgba(167, 139, 250, 0.12);

  /* Borders */
  --border: rgba(255, 255, 255, 0.06);
  --border-strong: rgba(255, 255, 255, 0.10);

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 20px 48px rgba(0, 0, 0, 0.5);

  /* Radii */
  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
}

/* ================================================================
   RESET & BASE
   ================================================================ */

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

html {
  scroll-behavior: smooth;
  background: var(--bg-root);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text-primary);
  background: var(--bg-primary);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Subtle grain overlay */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: -1;
  opacity: 0.35;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.08'/%3E%3C/svg%3E");
  pointer-events: none;
}

a { color: inherit; text-decoration: none; }

.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 28px;
}

/* ================================================================
   HEADER
   ================================================================ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(11, 20, 38, 0.88);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
}

.nav {
  max-width: 1140px;
  margin: 0 auto;
  height: 64px;
  padding: 0 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 20px;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.2px;
}

.brand-mark {
  width: 34px;
  height: 34px;
  display: block;
  object-fit: contain;
  flex: 0 0 auto;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link {
  padding: 7px 16px;
  border-radius: 999px;
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 600;
  transition: all 0.2s ease;
}

.nav-link:hover { color: var(--text-primary); background: rgba(255,255,255,0.04); }

.nav-link.active {
  color: var(--accent-soft);
  background: rgba(255, 92, 58, 0.10);
}

.nav-action {
  padding: 8px 18px;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  font-size: 14px;
  transition: all 0.2s ease;
  box-shadow: 0 4px 16px rgba(255, 92, 58, 0.3);
}

.nav-action:hover {
  background: #ff7b56;
  box-shadow: 0 8px 24px rgba(255, 92, 58, 0.42);
  transform: translateY(-1px);
}

/* Hamburger */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  color: var(--text-primary);
  line-height: 1;
}

.nav-toggle svg {
  display: block;
  width: 24px;
  height: 24px;
}

.nav-toggle .icon-close { display: none; }
.nav.open .nav-toggle .icon-menu { display: none; }
.nav.open .nav-toggle .icon-close { display: block; }

/* ================================================================
   SECTIONS
   ================================================================ */

.section { padding: 96px 0; }
.section.alt { background: var(--bg-root); }

.eyebrow {
  display: inline-block;
  margin: 0 0 16px;
  color: var(--accent-soft);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.section-title {
  margin: 0;
  font-size: 44px;
  line-height: 1.16;
  color: var(--text-primary);
  letter-spacing: -0.5px;
  font-weight: 800;
}

.section-lead {
  margin: 18px 0 0;
  max-width: 680px;
  color: var(--text-secondary);
  font-size: 18px;
  line-height: 1.75;
}

/* ================================================================
   HERO
   ================================================================ */

.hero {
  min-height: calc(100vh - 64px);
  display: flex;
  align-items: center;
  padding: 72px 0 80px;
  position: relative;
  overflow: hidden;
}

/* Ambient glow behind hero */
.hero::after {
  content: '';
  position: absolute;
  inset: -40% 0 -20%;
  background:
    radial-gradient(ellipse at 30% 20%, rgba(255, 92, 58, 0.10) 0%, transparent 50%),
    radial-gradient(ellipse at 75% 50%, rgba(91, 156, 245, 0.06) 0%, transparent 45%),
    radial-gradient(ellipse at 50% 80%, rgba(240, 165, 72, 0.05) 0%, transparent 40%);
  pointer-events: none;
  z-index: 0;
}

.hero > .container { position: relative; z-index: 1; }

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(360px, 0.8fr);
  gap: 60px;
  align-items: center;
}

.hero h1 {
  margin: 0;
  font-size: 62px;
  line-height: 1.1;
  color: #fff;
  letter-spacing: -0.8px;
  font-weight: 800;
}

.hero h1 span {
  background: linear-gradient(135deg, var(--accent-soft), var(--amber));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  margin: 28px 0 0;
  color: var(--text-secondary);
  font-size: 20px;
  line-height: 1.7;
  max-width: 580px;
}

.hero-actions,
.cta-actions {
  margin-top: 36px;
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 50px;
  padding: 0 28px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 15px;
  border: 1px solid transparent;
  transition: all 0.25s ease;
  cursor: pointer;
  letter-spacing: 0.01em;
}

.button.primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 8px 28px rgba(255, 92, 58, 0.36);
}

.button.primary:hover {
  background: #ff7b56;
  box-shadow: 0 14px 36px rgba(255, 92, 58, 0.48);
  transform: translateY(-2px);
}

.button.secondary {
  background: transparent;
  color: var(--text-primary);
  border-color: var(--border-strong);
}

.button.secondary:hover {
  border-color: rgba(255,255,255,0.22);
  background: rgba(255,255,255,0.04);
}

.hero-tags {
  margin-top: 32px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 0 14px;
  border-radius: 999px;
  color: var(--text-secondary);
  background: var(--bg-card);
  border: 1px solid var(--border);
  font-size: 13px;
  font-weight: 600;
}

/* ================================================================
   HERO PANEL (visual card)
   ================================================================ */

.hero-panel {
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  box-shadow: var(--shadow-lg), 0 0 80px rgba(255, 92, 58, 0.06);
  padding: 24px;
  position: relative;
  overflow: hidden;
}

.hero-panel::before {
  content: '';
  position: absolute;
  top: -40px;
  right: -40px;
  width: 120px;
  height: 120px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-glow), transparent 70%);
  pointer-events: none;
}

.expert-card {
  padding: 16px 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card-alt);
  transition: all 0.25s ease;
}

.expert-card:hover {
  border-color: var(--border-strong);
  box-shadow: 0 0 30px var(--accent-glow);
}

.expert-card + .expert-card { margin-top: 12px; }

.expert-head {
  display: flex;
  align-items: center;
  gap: 14px;
}

.expert-avatar {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border-radius: 13px;
  color: #fff;
  font-weight: 900;
  font-size: 18px;
  flex-shrink: 0;
  background: linear-gradient(135deg, var(--accent), #e04e2e);
  box-shadow: 0 4px 16px var(--accent-glow);
}

.expert-avatar.amber {
  background: linear-gradient(135deg, #f0a548, #d4882e);
  box-shadow: 0 4px 16px var(--amber-glow);
}

.expert-avatar.green {
  background: linear-gradient(135deg, #3dd6a4, #28a87d);
  box-shadow: 0 4px 16px var(--mint-glow);
}

.expert-avatar.purple {
  background: linear-gradient(135deg, #a78bfa, #7c3aed);
  box-shadow: 0 4px 16px var(--violet-glow);
}

.expert-avatar.rose {
  background: linear-gradient(135deg, #fb7185, #e11d48);
  box-shadow: 0 4px 16px rgba(251, 113, 133, 0.2);
}

.expert-card h3 {
  margin: 0;
  font-size: 16px;
  font-weight: 700;
  color: var(--text-primary);
}

.expert-card p {
  margin: 6px 0 0;
  color: var(--text-secondary);
  font-size: 13px;
  line-height: 1.55;
}

.flow-line {
  margin-top: 16px;
  padding: 14px 16px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  border-radius: var(--radius);
  background: var(--bg-root);
  border: 1px solid var(--border);
}

.flow-step {
  padding: 10px;
  border-radius: 9px;
  background: var(--bg-card);
  color: var(--text-primary);
  font-weight: 700;
  font-size: 13px;
  text-align: center;
}

/* ================================================================
   GRID & CARDS
   ================================================================ */

.grid { display: grid; gap: 20px; }
.grid.three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid.two { grid-template-columns: repeat(2, minmax(0, 1fr)); }

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 30px;
  transition: all 0.3s ease;
  position: relative;
}

.card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
  box-shadow: var(--shadow);
  transform: translateY(-3px);
}

.card h3 {
  margin: 0 0 10px;
  color: var(--text-primary);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.2px;
}

.card p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.7;
}

.card ul {
  margin: 14px 0 0;
  padding-left: 20px;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.8;
}

.card ul li { margin-bottom: 4px; }
.card ul li::marker { color: var(--accent); }

/* ================================================================
   ICON CIRCLES
   ================================================================ */

.icon-circle {
  width: 48px;
  height: 48px;
  margin-bottom: 18px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  font-size: 22px;
  flex-shrink: 0;
}

.icon-circle.coral  { background: rgba(255,92,58,0.12);  color: var(--accent-soft); }
.icon-circle.amber  { background: rgba(240,165,72,0.12); color: var(--amber); }
.icon-circle.blue   { background: rgba(91,156,245,0.10); color: var(--blue); }
.icon-circle.mint   { background: rgba(61,214,164,0.10); color: var(--mint); }
.icon-circle.violet { background: rgba(167,139,250,0.10); color: var(--violet); }

/* ================================================================
   CAPABILITY LIST
   ================================================================ */

.capability-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 36px;
}

.capability {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 24px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: all 0.25s ease;
}

.capability:hover {
  border-color: var(--border-strong);
  background: var(--bg-card-hover);
  box-shadow: var(--shadow-sm);
}

.capability strong {
  display: block;
  margin-bottom: 6px;
  color: var(--text-primary);
  font-size: 16px;
  font-weight: 700;
}

.capability span {
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.65;
}

/* ================================================================
   SCENARIO CARDS
   ================================================================ */

.scenario {
  display: grid;
  grid-template-columns: 130px minmax(0, 1fr);
  gap: 20px;
  align-items: start;
}

.scenario-label {
  padding: 8px 12px;
  border-radius: 9px;
  text-align: center;
  font-weight: 700;
  font-size: 13px;
}

.scenario-label {
  background: rgba(255,92,58,0.10);
  color: var(--accent-soft);
  border: 1px solid rgba(255,92,58,0.15);
}

.scenario-label.amber {
  background: rgba(240,165,72,0.10);
  color: var(--amber);
  border: 1px solid rgba(240,165,72,0.15);
}

.scenario-label.green {
  background: rgba(61,214,164,0.10);
  color: var(--mint);
  border: 1px solid rgba(61,214,164,0.15);
}

.scenario-label.purple {
  background: rgba(167,139,250,0.10);
  color: var(--violet);
  border: 1px solid rgba(167,139,250,0.15);
}

/* ================================================================
   SCENARIO DETAIL CARDS (scenarios.html)
   ================================================================ */

.scenario-detail {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.scenario-detail .scenario-header {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.scenario-detail .scenario-header h3 {
  margin: 0 0 4px;
}

.scenario-tagline {
  margin: 0;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.55;
}

.scenario-flow {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 18px;
  border-radius: var(--radius);
  background: var(--bg-root);
  border: 1px solid var(--border);
}

.flow-item strong {
  display: block;
  margin-bottom: 4px;
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 700;
}

.flow-item span {
  color: var(--text-secondary);
  font-size: 13px;
  line-height: 1.6;
}

.flow-item + .flow-item {
  padding-top: 14px;
  border-top: 1px solid var(--border);
}

.scenario-systems {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.system-tag {
  display: inline-flex;
  align-items: center;
  min-height: 26px;
  padding: 0 12px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  color: var(--blue);
  background: rgba(91, 156, 245, 0.08);
  border: 1px solid rgba(91, 156, 245, 0.14);
}

/* ================================================================
   CTA
   ================================================================ */

.cta {
  border-radius: var(--radius-xl);
  padding: 52px 56px;
  background: linear-gradient(160deg, #1a1035 0%, #1a0e28 40%, #0f1426 100%);
  border: 1px solid rgba(255,92,58,0.15);
  color: #fff;
  box-shadow: var(--shadow-lg), 0 0 100px rgba(255, 92, 58, 0.08);
  position: relative;
  overflow: hidden;
}

.cta::before {
  content: '';
  position: absolute;
  top: -80px;
  right: -60px;
  width: 220px;
  height: 220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255,92,58,0.12), transparent 70%);
  pointer-events: none;
}

.cta h2 {
  margin: 0;
  font-size: 36px;
  line-height: 1.22;
  font-weight: 800;
  letter-spacing: -0.4px;
  position: relative;
  z-index: 1;
}

.cta p {
  margin: 16px 0 0;
  max-width: 640px;
  color: rgba(255, 255, 255, 0.7);
  font-size: 17px;
  line-height: 1.7;
  position: relative;
  z-index: 1;
}

.cta-actions { position: relative; z-index: 1; }

.cta .button.primary {
  background: var(--accent);
}

.cta .button.secondary {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.2);
}

.cta .button.secondary:hover {
  background: rgba(255,255,255,0.08);
  border-color: rgba(255,255,255,0.35);
}

/* ================================================================
   FOOTER
   ================================================================ */

.site-footer {
  padding: 36px 0;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  background: var(--bg-root);
  font-size: 14px;
}

.footer-row {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.footer-links {
  display: flex;
  gap: 22px;
  flex-wrap: wrap;
}

.footer-links a {
  color: var(--text-muted);
  transition: color 0.2s ease;
}

.footer-links a:hover { color: var(--accent-soft); }

/* ================================================================
   LEGACY PAGES
   ================================================================ */

.legacy {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
  background: var(--bg-root);
}

.legacy-card {
  max-width: 640px;
  padding: 36px 40px;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  box-shadow: var(--shadow);
  text-align: center;
}

.legacy-card h1 {
  margin: 0 0 14px;
  color: var(--text-primary);
  font-size: 24px;
}

.legacy-card p {
  color: var(--text-secondary);
  margin-bottom: 20px;
}

/* ================================================================
   RESPONSIVE
   ================================================================ */

@media (max-width: 900px) {
  .nav {
    height: auto;
    min-height: 64px;
    flex-wrap: wrap;
    padding: 0 20px;
  }

  .nav-toggle { display: block; }

  .nav-links {
    display: none;
    width: 100%;
    flex-direction: column;
    gap: 2px;
    padding: 4px 0 14px;
    border-top: 1px solid var(--border);
  }

  .nav.open .nav-links { display: flex; }

  .nav-link {
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    font-size: 15px;
  }

  .nav-action {
    margin-top: 6px;
    text-align: center;
  }

  .hero { min-height: auto; }
  .hero-grid,
  .grid.three,
  .grid.two,
  .capability-list { grid-template-columns: 1fr; }
  .hero h1 { font-size: 42px; }
  .section-title { font-size: 32px; }
  .flow-line { grid-template-columns: 1fr; }
  .scenario { grid-template-columns: 1fr; }
  .cta { padding: 36px; }
  .cta h2 { font-size: 28px; }
}

@media (max-width: 560px) {
  .container { padding: 0 18px; }
  .nav { padding: 0 14px; }
  .hero h1 { font-size: 34px; }
  .hero-subtitle { font-size: 17px; }
  .section { padding: 60px 0; }
  .section-title { font-size: 28px; }
  .card { padding: 22px; }
  .capability { padding: 18px; }
}