:root {
  --bg: #0b1220;
  --surface: #111b2d;
  --surface-2: #16243a;
  --border: #24364d;
  --text: #e8eef6;
  --text-2: #9fb1c5;
  --accent: #60a5fa;
  --accent-dark: #93c5fd;
  --shadow: 0 14px 36px rgba(0, 0, 0, 0.35);
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  padding: 14px 20px;
  background: rgba(11,18,32,0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.back-link {
  color: var(--accent-dark);
  text-decoration: none;
  font-weight: 600;
}

.page {
  max-width: 1180px;
  margin: 0 auto;
  padding: 24px 20px 48px;
}

.hero {
  display: grid;
  grid-template-columns: 1.35fr 0.95fr;
  gap: 24px;
  align-items: center;
  padding: 28px;
  background: linear-gradient(135deg, #111b2d 0%, #0f172a 58%);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.hero-meta {
  color: var(--accent-dark);
  font-size: 0.92rem;
  font-weight: 700;
  margin-bottom: 8px;
}

#page-title {
  margin: 0;
  font-size: 2rem;
  line-height: 1.2;
}

.hero-subtitle {
  margin: 10px 0 0;
  color: var(--text-2);
  font-size: 1rem;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 14px;
  border-radius: 10px;
  text-decoration: none;
  font-weight: 600;
  transition: transform 0.12s ease, filter 0.12s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-secondary {
  background: #1c2c45;
  color: var(--accent-dark);
}

.hero-image-wrap {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 260px;
  padding: 10px;
  background: rgba(15,23,42,0.72);
  border: 1px solid rgba(96,165,250,0.18);
  border-radius: 16px;
}

#hero-image {
  display: block;
  max-width: 100%;
  max-height: 360px;
  object-fit: contain;
}

.layout {
  display: grid;
  grid-template-columns: minmax(0, 2fr) minmax(280px, 0.95fr);
  gap: 20px;
  margin-top: 22px;
}

.content-card,
.side-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: var(--shadow);
}

.content-card {
  padding: 24px;
}

.content-card h2,
.side-card h2 {
  margin: 0 0 14px;
  font-size: 1.08rem;
}

.lead {
  margin: 0 0 18px;
  color: var(--text-2);
  line-height: 1.8;
  font-size: 1rem;
}

.paragraphs p {
  margin: 0 0 14px;
  line-height: 1.9;
  font-size: 1rem;
}

.source-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.source-sections {
  margin-top: 22px;
  display: grid;
  gap: 18px;
}

.source-section {
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

.source-section h3 {
  margin: 0 0 10px;
  font-size: 1.06rem;
}

.source-section p {
  margin: 0 0 12px;
  line-height: 1.9;
}

.sidebar {
  display: grid;
  gap: 20px;
  align-content: start;
}

.side-card {
  padding: 18px;
}

.facts-list {
  display: grid;
  grid-template-columns: minmax(86px, 110px) 1fr;
  gap: 10px 12px;
  margin: 0;
}

.facts-list dt {
  color: var(--text-2);
  font-weight: 600;
}

.facts-list dd {
  margin: 0;
  font-weight: 500;
  word-break: break-word;
}

.muted {
  color: var(--text-2);
  line-height: 1.7;
}

.text-link {
  color: var(--accent-dark);
  text-decoration: none;
  font-weight: 600;
}

.model-card {
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  background: linear-gradient(180deg, #0f172a 0%, #111827 100%);
}

.nav-links {
  display: grid;
  gap: 10px;
}

.nav-link {
  display: block;
  padding: 10px 12px;
  border-radius: 10px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--accent-dark);
  text-decoration: none;
  font-weight: 600;
}

.empty-state {
  padding: 40px 24px;
  text-align: center;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: var(--shadow);
}

@media (max-width: 920px) {
  .hero,
  .layout {
    grid-template-columns: 1fr;
  }

  #page-title {
    font-size: 1.6rem;
  }
}