/* AI 工具对比站 - 全局样式 */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #dbeafe;
  --success: #16a34a;
  --success-light: #dcfce7;
  --warning: #f59e0b;
  --warning-light: #fef3c7;
  --danger: #dc2626;
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
  --radius: 8px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);
  --max-width: 1320px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  color: var(--gray-800);
  background: #fff;
  line-height: 1.6;
  font-size: 16px;
}

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

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* Header */
.site-header {
  border-bottom: 1px solid var(--gray-200);
  padding: 16px 0;
  position: sticky;
  top: 0;
  background: #fff;
  z-index: 100;
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.site-logo { font-size: 20px; font-weight: 700; color: var(--gray-900); }
.site-logo:hover { text-decoration: none; color: var(--primary); }
.site-nav { display: flex; gap: 24px; align-items: center; }
.site-nav a { color: var(--gray-600); font-size: 15px; }
.site-nav a:hover { color: var(--primary); text-decoration: none; }

/* Hero */
.hero {
  background: linear-gradient(135deg, var(--primary) 0%, #7c3aed 100%);
  color: #fff;
  padding: 64px 0;
  text-align: center;
}
.hero h1 { font-size: 36px; margin-bottom: 16px; }
.hero p { font-size: 18px; opacity: 0.9; max-width: 600px; margin: 0 auto 32px; }
.hero-search {
  max-width: 480px;
  margin: 0 auto;
  position: relative;
}
.hero-search input {
  width: 100%;
  padding: 14px 20px;
  border: none;
  border-radius: 40px;
  font-size: 16px;
  outline: none;
  box-shadow: var(--shadow-lg);
}
.hero-search input::placeholder { color: var(--gray-400); }

/* Section */
.section { padding: 48px 0; }
.section-title {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 24px;
  color: var(--gray-900);
}

/* Tool Cards */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
}
.tool-card {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 20px;
  transition: box-shadow 0.2s, transform 0.2s;
  display: flex;
  flex-direction: column;
}
.tool-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.tool-card-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}
.tool-card-logo {
  width: 40px;
  height: 40px;
  border-radius: 8px;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: var(--primary);
  font-size: 16px;
}
.tool-card-name { font-size: 18px; font-weight: 600; }
.tool-card-company { font-size: 13px; color: var(--gray-500); }
.tool-card-tagline {
  font-size: 14px;
  color: var(--gray-600);
  margin-bottom: 12px;
  flex: 1;
}
.tool-card-tags { display: flex; gap: 8px; flex-wrap: wrap; }
.tag {
  font-size: 12px;
  padding: 3px 10px;
  border-radius: 20px;
  background: var(--gray-100);
  color: var(--gray-600);
}
.tag-free { background: var(--success-light); color: var(--success); }
.tag-category { background: var(--primary-light); color: var(--primary); }

/* Comparison Cards */
.compare-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 16px;
}
.compare-card {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  transition: box-shadow 0.2s;
}
.compare-card:hover {
  box-shadow: var(--shadow-md);
  text-decoration: none;
}
.compare-vs {
  font-weight: 700;
  color: var(--primary);
  font-size: 14px;
  white-space: nowrap;
}
.compare-card-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--gray-800);
}

/* Category Cards */
.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}
.category-card {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
  transition: box-shadow 0.2s, border-color 0.2s;
}
.category-card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
  text-decoration: none;
}
.category-card-icon { font-size: 32px; margin-bottom: 12px; }
.category-card-name { font-size: 18px; font-weight: 600; color: var(--gray-900); margin-bottom: 8px; }
.category-card-desc { font-size: 14px; color: var(--gray-500); }
.category-card-count { font-size: 13px; color: var(--primary); margin-top: 8px; }

/* Tool Detail Page */
.tool-detail { padding: 40px 0; }
.tool-detail-header {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--gray-200);
}
.tool-detail-logo {
  width: 64px;
  height: 64px;
  border-radius: 12px;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: var(--primary);
  font-size: 24px;
  flex-shrink: 0;
}
.tool-detail-info h1 { font-size: 28px; margin-bottom: 4px; }
.tool-detail-info .company { color: var(--gray-500); font-size: 15px; margin-bottom: 8px; }
.tool-detail-info .tagline { font-size: 16px; color: var(--gray-600); }
.tool-detail-actions { margin-left: auto; display: flex; gap: 12px; }
.btn {
  display: inline-block;
  padding: 10px 20px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  border: none;
  transition: background 0.2s;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); color: #fff; text-decoration: none; }
.btn-outline { border: 1px solid var(--gray-300); color: var(--gray-700); background: #fff; }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); text-decoration: none; }

/* Pricing Table */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 16px;
  margin-bottom: 32px;
}
.pricing-card {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 20px;
  text-align: center;
}
.pricing-card.featured { border-color: var(--primary); box-shadow: 0 0 0 1px var(--primary); }
.pricing-plan { font-size: 16px; font-weight: 600; margin-bottom: 8px; }
.pricing-price { font-size: 28px; font-weight: 700; color: var(--primary); }
.pricing-price span { font-size: 14px; color: var(--gray-500); font-weight: 400; }
.pricing-features { list-style: none; margin-top: 16px; text-align: left; }
.pricing-features li {
  font-size: 13px;
  padding: 4px 0;
  color: var(--gray-600);
  padding-left: 18px;
  position: relative;
}
.pricing-features li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--success);
  font-weight: 700;
}

/* Pros/Cons */
.pros-cons {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 32px;
}
.pros-list, .cons-list { list-style: none; }
.pros-list li, .cons-list li {
  padding: 8px 0 8px 24px;
  position: relative;
  font-size: 14px;
}
.pros-list li::before { content: "✓"; position: absolute; left: 0; color: var(--success); font-weight: 700; }
.cons-list li::before { content: "✗"; position: absolute; left: 0; color: var(--danger); font-weight: 700; }

/* Comparison Page */
.compare-table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 32px;
}
.compare-table th, .compare-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--gray-200);
  font-size: 14px;
}
.compare-table th { background: var(--gray-50); font-weight: 600; color: var(--gray-700); }
.compare-table .winner-cell { background: var(--success-light); }
.compare-table .dimension-cell { font-weight: 600; color: var(--gray-700); width: 120px; }
.compare-table-wrapper { overflow-x: auto; -webkit-overflow-scrolling: touch; }

.verdict-box {
  background: var(--primary-light);
  border-left: 4px solid var(--primary);
  padding: 16px 20px;
  border-radius: 0 var(--radius) var(--radius) 0;
  margin-bottom: 32px;
  font-size: 15px;
}

.best-for-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 32px;
}
.best-for-card {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 20px;
}
.best-for-card h3 { font-size: 16px; margin-bottom: 8px; color: var(--primary); }
.best-for-card p { font-size: 14px; color: var(--gray-600); }

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
  margin-bottom: 32px;
}
.feature-item {
  padding: 16px;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
}
.feature-item h4 { font-size: 14px; font-weight: 600; margin-bottom: 6px; color: var(--gray-800); }
.feature-item p { font-size: 13px; color: var(--gray-600); }

/* Alternatives Page */
.alt-list { display: flex; flex-direction: column; gap: 16px; }
.alt-card {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 20px;
}
.alt-card h3 { font-size: 17px; margin-bottom: 8px; }
.alt-card .alt-reason { font-size: 14px; color: var(--gray-600); margin-bottom: 12px; }
.alt-card .alt-pros-cons { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }

/* FAQ */
.faq-list { max-width: 800px; }
.faq-item { border-bottom: 1px solid var(--gray-200); padding: 16px 0; }
.faq-item h3 { font-size: 15px; font-weight: 600; margin-bottom: 8px; cursor: pointer; }
.faq-item p { font-size: 14px; color: var(--gray-600); }

/* Footer */
.site-footer {
  border-top: 1px solid var(--gray-200);
  padding: 32px 0;
  margin-top: 48px;
  color: var(--gray-500);
  font-size: 14px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 32px;
}
.footer-brand p { margin-top: 8px; }
.footer-links h4 { font-size: 14px; font-weight: 600; color: var(--gray-700); margin-bottom: 12px; }
.footer-links ul { list-style: none; }
.footer-links li { margin-bottom: 8px; }
.footer-links a { color: var(--gray-500); font-size: 13px; }
.footer-links a:hover { color: var(--primary); }
.footer-bottom {
  margin-top: 24px;
  padding-top: 16px;
  border-top: 1px solid var(--gray-200);
  text-align: center;
  font-size: 13px;
}

/* Breadcrumb */
.breadcrumb {
  padding: 12px 0;
  font-size: 13px;
  color: var(--gray-500);
}
.breadcrumb a { color: var(--gray-500); }
.breadcrumb a:hover { color: var(--primary); }
.breadcrumb span { margin: 0 6px; }

/* Responsive */
@media (max-width: 768px) {
  .hero { padding: 40px 0; }
  .hero h1 { font-size: 26px; }
  .hero p { font-size: 15px; }
  .tool-grid { grid-template-columns: 1fr; }
  .compare-grid { grid-template-columns: 1fr; }
  .pros-cons { grid-template-columns: 1fr; }
  .best-for-grid { grid-template-columns: 1fr; }
  .pricing-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 24px; }
  .tool-detail-header { flex-direction: column; }
  .tool-detail-actions { margin-left: 0; }
  .site-nav { gap: 16px; }
  .category-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr; }
  .alt-card .alt-pros-cons { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .site-nav { gap: 12px; }
  .site-nav a { font-size: 13px; }
  .footer-grid { grid-template-columns: 1fr; }
}