:root {
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-card: #1c2128;
  --bg-hover: #21262d;
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --accent: #58a6ff;
  --accent-hover: #79c0ff;
  --border: #30363d;
  --success: #3fb950;
  --warning: #d29922;
  --danger: #f85149;
  --radius: 8px;
  --shadow: 0 4px 12px rgba(0,0,0,0.3);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  font-size: 16px;
}

a { color: var(--accent); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent-hover); }

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* Header */
.site-header {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon {
  width: 32px; height: 32px;
  background: linear-gradient(135deg, var(--accent), #a371f7);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1rem;
}

.main-nav { display: flex; gap: 28px; }
.main-nav a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
}
.main-nav a:hover, .main-nav a.active {
  color: var(--text-primary);
  border-bottom-color: var(--accent);
}

/* Hero */
.hero {
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
  border-bottom: 1px solid var(--border);
  padding: 80px 0 60px;
  text-align: center;
}

.hero h1 {
  font-size: 2.8rem;
  font-weight: 800;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--accent), #a371f7);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.2rem;
  color: var(--text-secondary);
  max-width: 700px;
  margin: 0 auto 32px;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  margin-top: 40px;
}

.stat-item { text-align: center; }
.stat-number {
  font-size: 2rem;
  font-weight: 700;
  color: var(--accent);
}
.stat-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 4px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  border: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), #a371f7);
  color: #fff;
}
.btn-primary:hover { opacity: 0.9; transform: translateY(-1px); }

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border);
}
.btn-secondary:hover { background: var(--bg-hover); }

/* Section */
.section { padding: 60px 0; }
.section-title {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.section-desc {
  color: var(--text-secondary);
  margin-bottom: 32px;
}

/* Cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 20px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: all 0.2s;
}
.card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.card-badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  margin-bottom: 12px;
}
.badge-case { background: rgba(88,166,255,0.15); color: var(--accent); }
.badge-guide { background: rgba(63,185,80,0.15); color: var(--success); }
.badge-solution { background: rgba(210,153,34,0.15); color: var(--warning); }
.badge-review { background: rgba(168,85,247,0.15); color: #a855f7; }

.card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text-primary);
}
.card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
}

.card-meta {
  display: flex;
  gap: 16px;
  margin-top: 16px;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

/* Tags */
.tag-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.tag {
  padding: 3px 10px;
  background: var(--bg-hover);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

/* CTA Section */
.cta-section {
  background: linear-gradient(135deg, rgba(88,166,255,0.1), rgba(163,113,247,0.1));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 48px;
  text-align: center;
  margin: 40px 0;
}
.cta-section h2 { font-size: 1.6rem; margin-bottom: 12px; }
.cta-section p { color: var(--text-secondary); margin-bottom: 24px; }

/* Footer */
.site-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 40px 0 24px;
  margin-top: 60px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 32px;
}
.footer-brand p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-top: 8px;
}
.footer-links h4 {
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 12px;
}
.footer-links a {
  display: block;
  color: var(--text-secondary);
  font-size: 0.85rem;
  padding: 4px 0;
}
.footer-links a:hover { color: var(--accent); }
.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 20px;
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.85rem;
}

/* Content Page */
.page-header {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  padding: 48px 0 32px;
}
.page-header h1 { font-size: 2.2rem; margin-bottom: 8px; }
.page-header .meta { color: var(--text-secondary); font-size: 0.9rem; }

.content-body {
  max-width: 800px;
  margin: 0 auto;
  padding: 40px 24px;
}

.content-body h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin: 40px 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}
.content-body h3 {
  font-size: 1.2rem;
  font-weight: 600;
  margin: 28px 0 12px;
  color: var(--accent);
}
.content-body p {
  margin-bottom: 16px;
  color: var(--text-secondary);
}
.content-body ul, .content-body ol {
  margin: 0 0 16px 24px;
  color: var(--text-secondary);
}
.content-body li { margin-bottom: 8px; }
.content-body strong { color: var(--text-primary); }
.content-body code {
  background: var(--bg-hover);
  padding: 2px 8px;
  border-radius: 4px;
  font-family: "SF Mono", Monaco, monospace;
  font-size: 0.9em;
}
.content-body pre {
  background: var(--bg-secondary);
  padding: 16px;
  border-radius: var(--radius);
  overflow-x: auto;
  margin: 16px 0;
}
.content-body blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 16px;
  margin: 20px 0;
  color: var(--text-secondary);
  font-style: italic;
}

/* Table */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  font-size: 0.9rem;
}
th, td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
th {
  background: var(--bg-secondary);
  font-weight: 600;
  color: var(--text-primary);
}
tr:hover { background: var(--bg-hover); }

/* Breadcrumb */
.breadcrumb {
  display: flex;
  gap: 8px;
  align-items: center;
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 16px;
}
.breadcrumb a { color: var(--text-secondary); }
.breadcrumb a:hover { color: var(--accent); }

/* Ad container */
.ad-container {
  background: var(--bg-card);
  border: 1px dashed var(--border);
  border-radius: var(--radius);
  padding: 20px;
  margin: 24px 0;
  text-align: center;
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  font-size: 0.85rem;
}

/* Responsive */
@media (max-width: 768px) {
  .hero h1 { font-size: 1.8rem; }
  .hero-stats { flex-direction: column; gap: 20px; }
  .card-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .main-nav { display: none; }
}