:root {
  --bg: #fafaf7;
  --fg: #1f2937;
  --muted: #6b7280;
  --accent: #2563eb;
  --accent-soft: #dbeafe;
  --border: #e5e7eb;
  --card-bg: #ffffff;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
  --radius: 8px;
}

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

html, body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  line-height: 1.55;
  color: var(--fg);
  background: var(--bg);
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

.container {
  max-width: 920px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ---------- Header ---------- */
.site-header {
  background: var(--card-bg);
  border-bottom: 1px solid var(--border);
  padding: 22px 0;
  margin-bottom: 36px;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--fg);
}
.brand:hover {
  text-decoration: none;
}

.brand-mark {
  font-size: 22px;
  line-height: 1;
  color: var(--accent);
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-name {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.3px;
}

.brand-tagline {
  font-size: 11px;
  color: var(--muted);
  letter-spacing: 0.4px;
  margin-top: 1px;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  font-size: 13px;
}

.site-nav a {
  color: var(--muted);
  font-weight: 500;
  transition: color 0.15s;
}
.site-nav a:hover {
  color: var(--accent);
  text-decoration: none;
}

/* ---------- Section ---------- */
.section {
  margin-bottom: 44px;
}

.section-head {
  margin-bottom: 16px;
}

.section-title {
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.4px;
  color: var(--muted);
}

.section-sub {
  font-size: 13px;
  color: var(--muted);
  margin-top: 4px;
}

/* ---------- Card Grid (responsive) ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 12px;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  transition: transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease;
}

.card:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
  border-color: var(--accent-soft);
}

.card-head {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.card-icon {
  font-size: 15px;
  flex-shrink: 0;
  width: 22px;
  text-align: center;
}

.card-title {
  font-size: 15px;
  font-weight: 600;
  flex: 1;
  min-width: 0;
}

.card-title a {
  color: var(--fg);
}
.card-title a:hover {
  color: var(--accent);
  text-decoration: underline;
}

.card-tag {
  font-size: 10px;
  font-weight: 600;
  color: var(--muted);
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 2px 8px;
  border-radius: 999px;
  letter-spacing: 0.4px;
  text-transform: uppercase;
  flex-shrink: 0;
  white-space: nowrap;
}

.card-desc {
  font-size: 13px;
  color: var(--muted);
  margin-top: 6px;
  margin-left: 30px;
  line-height: 1.55;
}

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 24px 0;
  margin-top: 48px;
  text-align: center;
  font-size: 12px;
  color: var(--muted);
}

/* ---------- Responsive ---------- */
@media (max-width: 600px) {
  .container {
    padding: 0 16px;
  }
  .site-header {
    padding: 18px 0;
    margin-bottom: 28px;
  }
  .site-header .container {
    align-items: flex-start;
  }
  .brand-name {
    font-size: 16px;
  }
  .site-nav {
    gap: 14px;
    font-size: 12px;
  }
  .card-desc {
    margin-left: 0;
  }
  .card-head {
    align-items: flex-start;
  }
}

@media (min-width: 720px) {
  .container {
    padding: 0 24px;
  }
}