:root {
  --brand: #1f3a5f;
  --brand-soft: #eef3f8;
  --brand-border: #d7e1ee;
  --text-main: #1f2a37;
  --text-sub: #4b5563;
  --card-shadow: 0 8px 24px rgba(18, 38, 63, 0.06);
}

body {
  color: var(--text-main);
  background: #f8fafc;
  font-family: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

.navbar-custom .navbar-brand {
  font-weight: 700;
  letter-spacing: 0.02em;
}

.page-section {
  margin: 36px 0;
}

.section-title {
  margin: 0 0 16px;
  color: var(--brand);
  font-weight: 700;
}

.section-desc {
  color: var(--text-sub);
  margin-bottom: 18px;
}

.hero-panel {
  background: linear-gradient(135deg, #f5f8fc 0%, #edf3fa 100%);
  border: 1px solid var(--brand-border);
  border-radius: 12px;
  box-shadow: var(--card-shadow);
  padding: 28px;
}

.hero-panel h1 {
  margin-top: 0;
  margin-bottom: 12px;
  color: #16283f;
  font-size: 34px;
  font-weight: 800;
}

.hero-panel .hero-subtitle {
  margin-bottom: 12px;
  color: #1f3a5f;
  font-size: 18px;
  line-height: 1.8;
}

.hero-panel .hero-meta {
  color: var(--text-sub);
  margin-bottom: 20px;
}

.btn-brand {
  border-radius: 8px;
  padding: 10px 18px;
  font-weight: 600;
  border: 1px solid var(--brand);
  transition: all 0.2s ease;
}

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

.btn-brand-primary:hover,
.btn-brand-primary:focus {
  color: #fff;
  background: #172f4d;
  border-color: #172f4d;
}

.btn-brand-secondary {
  background: #fff;
  color: var(--brand);
}

.btn-brand-secondary:hover,
.btn-brand-secondary:focus {
  color: #172f4d;
  border-color: #172f4d;
}

.grid-cards {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 16px;
}

.grid-col-4 {
  grid-column: span 4;
}

.grid-col-6 {
  grid-column: span 6;
}

.grid-col-3 {
  grid-column: span 3;
}

.info-card {
  background: #fff;
  border: 1px solid #e5eaf1;
  border-radius: 12px;
  box-shadow: var(--card-shadow);
  padding: 18px;
  height: 100%;
}

.info-card h3,
.info-card h4 {
  margin-top: 0;
  margin-bottom: 8px;
  color: #1f3a5f;
  font-weight: 700;
}

.info-card p {
  margin: 0;
  color: var(--text-sub);
  line-height: 1.75;
}

.badge-soft {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 99px;
  background: #edf3fb;
  border: 1px solid #d2e0f1;
  color: #274a74;
  font-size: 12px;
  margin-right: 6px;
  margin-bottom: 6px;
}

.post-card {
  background: #fff;
  border: 1px solid #e5eaf1;
  border-radius: 12px;
  padding: 18px;
  box-shadow: var(--card-shadow);
  margin-bottom: 14px;
}

.post-card h3 {
  margin-top: 0;
  margin-bottom: 8px;
  font-size: 22px;
}

.post-card .meta {
  color: #6b7280;
  font-size: 13px;
  margin-bottom: 10px;
}

.post-card .excerpt {
  color: #334155;
  line-height: 1.8;
}

.note-filter {
  margin-bottom: 18px;
}

.note-filter .tag {
  display: inline-block;
  padding: 6px 12px;
  border-radius: 20px;
  border: 1px solid #d9e2ef;
  color: #334155;
  margin-right: 8px;
  margin-bottom: 8px;
  text-decoration: none;
}

.note-filter .tag:hover,
.note-filter .tag.active {
  border-color: var(--brand);
  color: var(--brand);
}

.post-container {
  max-width: 860px;
  line-height: 1.9;
  font-size: 16px;
}

.post-container h1,
.post-container h2,
.post-container h3,
.post-container h4 {
  margin-top: 1.6em;
  margin-bottom: 0.6em;
  color: #1f3a5f;
}

.post-container pre {
  position: relative;
  border-radius: 10px;
  border: 1px solid #e2e8f0;
  background: #f8fafc;
  padding-top: 34px;
}

.copy-code-btn {
  position: absolute;
  top: 6px;
  right: 8px;
  border: 1px solid #d7e1ee;
  background: #fff;
  border-radius: 6px;
  padding: 2px 8px;
  font-size: 12px;
  color: #334155;
}

.post-meta-extra {
  margin-top: 12px;
  color: #64748b;
  font-size: 13px;
}

.related-posts {
  margin-top: 28px;
  padding-top: 14px;
  border-top: 1px solid #e5eaf1;
}

.related-posts ul {
  padding-left: 18px;
}

.related-posts li {
  margin-bottom: 8px;
}

.archive-block {
  margin-bottom: 24px;
}

.archive-block h3 {
  margin-top: 0;
  color: var(--brand);
}

.coming-soon {
  color: #64748b;
  font-style: italic;
}

@media (max-width: 992px) {
  .grid-col-4,
  .grid-col-3,
  .grid-col-6 {
    grid-column: span 6;
  }
}

@media (max-width: 768px) {
  .hero-panel {
    padding: 18px;
  }

  .hero-panel h1 {
    font-size: 28px;
  }

  .grid-col-4,
  .grid-col-3,
  .grid-col-6 {
    grid-column: span 12;
  }

  .post-container {
    font-size: 15px;
  }
}