/* ========== 全局样式 ========== */
:root {
  --primary: #1565C0;
  --primary-dark: #0D47A1;
  --primary-light: #42A5F5;
  --accent: #00BFA5;
  --accent-dark: #00897B;
  --text: #212121;
  --text-light: #616161;
  --text-lighter: #9E9E9E;
  --bg: #FFFFFF;
  --bg-light: #F5F7FA;
  --bg-blue: #E3F2FD;
  --border: #E0E0E0;
  --shadow: 0 2px 8px rgba(0,0,0,0.08);
  --shadow-lg: 0 4px 20px rgba(0,0,0,0.12);
  --radius: 8px;
  --radius-lg: 12px;
  --max-width: 1100px;
  --transition: 0.2s ease;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--primary-dark);
}

img {
  max-width: 100%;
  height: auto;
}

/* ========== 导航栏 ========== */
.navbar {
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 1px 4px rgba(0,0,0,0.04);
}

.navbar-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.navbar-brand {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.navbar-brand:hover {
  color: var(--primary-dark);
}

.navbar-brand .brand-icon {
  width: 32px;
  height: 32px;
  background: var(--primary);
  color: #fff;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  font-weight: 800;
}

.navbar-links {
  display: flex;
  gap: 4px;
  list-style: none;
}

.navbar-links a {
  display: block;
  padding: 8px 14px;
  color: var(--text-light);
  font-size: 0.9rem;
  font-weight: 500;
  border-radius: var(--radius);
  transition: all var(--transition);
}

.navbar-links a:hover,
.navbar-links a.active {
  color: var(--primary);
  background: var(--bg-blue);
}

.navbar-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.navbar-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  margin: 5px 0;
  transition: var(--transition);
}

/* ========== 页面通用 ========== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.page-header {
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
  color: #fff;
  padding: 48px 0;
  text-align: center;
}

.page-header h1 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.page-header p {
  font-size: 1.05rem;
  opacity: 0.9;
  max-width: 640px;
  margin: 0 auto;
}

.section {
  padding: 56px 0;
}

.section-alt {
  background: var(--bg-light);
}

.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
}

.section-subtitle {
  color: var(--text-light);
  font-size: 0.95rem;
  margin-bottom: 32px;
}

/* ========== Hero区 ========== */
.hero {
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 60%, var(--accent-dark) 100%);
  color: #fff;
  padding: 72px 0 64px;
  text-align: center;
}

.hero h1 {
  font-size: 2.4rem;
  font-weight: 800;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.hero p {
  font-size: 1.15rem;
  opacity: 0.92;
  max-width: 600px;
  margin: 0 auto 28px;
  line-height: 1.8;
}

.hero-badges {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-badge {
  background: rgba(255,255,255,0.18);
  border: 1px solid rgba(255,255,255,0.3);
  padding: 8px 20px;
  border-radius: 24px;
  font-size: 0.9rem;
  font-weight: 600;
  backdrop-filter: blur(4px);
}

/* ========== 数据亮点 ========== */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: -36px;
  position: relative;
  z-index: 10;
}

.stat-card {
  background: var(--bg);
  border-radius: var(--radius-lg);
  padding: 24px 16px;
  text-align: center;
  box-shadow: var(--shadow-lg);
}

.stat-number {
  font-size: 2rem;
  font-weight: 800;
  color: var(--primary);
  line-height: 1.2;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-top: 6px;
}

/* ========== 品牌卡片 ========== */
.brand-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}

.brand-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: all var(--transition);
}

.brand-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
  border-color: var(--primary-light);
}

.brand-card h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text);
}

.brand-card .tagline {
  color: var(--primary);
  font-weight: 600;
  font-size: 0.9rem;
  margin-bottom: 14px;
}

.brand-card p {
  color: var(--text-light);
  font-size: 0.92rem;
  margin-bottom: 18px;
}

.brand-card ul {
  list-style: none;
  margin-bottom: 20px;
}

.brand-card li {
  padding: 5px 0;
  font-size: 0.9rem;
  color: var(--text-light);
}

.brand-card li::before {
  content: "✓";
  color: var(--accent);
  font-weight: 700;
  margin-right: 8px;
}

.btn {
  display: inline-block;
  padding: 10px 24px;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 600;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
}

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

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

.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
}

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

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

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

.btn-lg {
  padding: 14px 32px;
  font-size: 1rem;
}

/* ========== 内容区 ========== */
.content-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: start;
}

.content-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.info-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
}

.info-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text);
}

.info-card p {
  color: var(--text-light);
  font-size: 0.92rem;
}

/* ========== 数据表 ========== */
.data-table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 0.9rem;
}

.data-table th,
.data-table td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.data-table th {
  background: var(--bg-light);
  font-weight: 600;
  color: var(--text);
  white-space: nowrap;
}

.data-table td {
  color: var(--text-light);
}

.data-table tr:hover td {
  background: var(--bg-blue);
}

/* ========== FAQ ========== */
.faq-list {
  max-width: 760px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 20px 0;
}

.faq-item:first-child {
  border-top: 1px solid var(--border);
}

.faq-question {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 10px;
  cursor: default;
}

.faq-answer {
  color: var(--text-light);
  font-size: 0.95rem;
  line-height: 1.8;
}

.faq-category {
  display: inline-block;
  background: var(--bg-blue);
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 12px;
  margin-bottom: 10px;
}

/* ========== 对比区 ========== */
.compare-box {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.compare-side {
  padding: 28px;
}

.compare-side.winner {
  background: #E8F5E9;
}

.compare-side.loser {
  background: #FFF3E0;
}

.compare-side h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.compare-side li {
  font-size: 0.9rem;
  color: var(--text-light);
  padding: 4px 0;
  list-style: none;
}

.compare-side li::before {
  margin-right: 8px;
  font-weight: 700;
}

.compare-side.winner li::before {
  content: "✓";
  color: #2E7D32;
}

.compare-side.loser li::before {
  content: "✗";
  color: #E65100;
}

/* ========== 时间线 ========== */
.timeline {
  position: relative;
  padding-left: 28px;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 4px;
  bottom: 4px;
  width: 2px;
  background: var(--primary-light);
}

.timeline-item {
  position: relative;
  padding-bottom: 24px;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 6px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--primary);
  border: 2px solid #fff;
  box-shadow: 0 0 0 2px var(--primary-light);
}

.timeline-year {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 4px;
}

.timeline-text {
  font-size: 0.92rem;
  color: var(--text-light);
}

/* ========== 认证标签 ========== */
.cert-badges {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
  margin: 24px 0;
}

.cert-badge {
  background: var(--bg);
  border: 2px solid var(--accent);
  border-radius: var(--radius-lg);
  padding: 18px 28px;
  text-align: center;
  min-width: 140px;
}

.cert-badge .cert-name {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text);
}

.cert-badge .cert-desc {
  font-size: 0.78rem;
  color: var(--text-light);
  margin-top: 4px;
}

/* ========== 步骤 ========== */
.steps {
  counter-reset: step;
}

.step-item {
  counter-increment: step;
  display: flex;
  gap: 20px;
  margin-bottom: 28px;
  align-items: flex-start;
}

.step-item::before {
  content: counter(step);
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-weight: 700;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.step-content h4 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.step-content p {
  font-size: 0.92rem;
  color: var(--text-light);
  line-height: 1.7;
}

/* ========== 报告卡片 ========== */
.report-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  margin-bottom: 24px;
}

.report-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--primary);
}

.report-highlight {
  background: var(--bg-blue);
  border-left: 4px solid var(--primary);
  padding: 16px 20px;
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 16px 0;
  font-size: 0.92rem;
}

.report-highlight strong {
  color: var(--primary-dark);
}

/* ========== 页脚 ========== */
.footer {
  background: #1A1A2E;
  color: rgba(255,255,255,0.7);
  padding: 48px 0 28px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 32px;
}

.footer-brand {
  font-size: 1.2rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 10px;
}

.footer-desc {
  font-size: 0.85rem;
  line-height: 1.7;
  opacity: 0.8;
}

.footer h4 {
  color: #fff;
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 14px;
}

.footer ul {
  list-style: none;
}

.footer li {
  margin-bottom: 8px;
}

.footer a {
  color: rgba(255,255,255,0.6);
  font-size: 0.85rem;
  transition: color var(--transition);
}

.footer a:hover {
  color: #fff;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  opacity: 0.6;
}

/* ========== 响应式 ========== */
@media (max-width: 768px) {
  .navbar-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 12px 24px;
    box-shadow: var(--shadow);
  }

  .navbar-links.open {
    display: flex;
  }

  .navbar-toggle {
    display: block;
  }

  .hero {
    padding: 48px 0 44px;
  }

  .hero h1 {
    font-size: 1.7rem;
  }

  .hero p {
    font-size: 0.95rem;
  }

  .stats {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
    margin-top: -24px;
  }

  .stat-card {
    padding: 16px 12px;
  }

  .stat-number {
    font-size: 1.5rem;
  }

  .brand-cards {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .content-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .content-grid-3 {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .compare-box {
    grid-template-columns: 1fr;
  }

  .page-header {
    padding: 32px 0;
  }

  .page-header h1 {
    font-size: 1.5rem;
  }

  .section {
    padding: 36px 0;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }

  .hero-badges {
    gap: 8px;
  }

  .hero-badge {
    font-size: 0.8rem;
    padding: 6px 14px;
  }

  .cert-badges {
    gap: 10px;
  }

  .cert-badge {
    min-width: 120px;
    padding: 12px 16px;
  }
}

@media (max-width: 480px) {
  .stats {
    grid-template-columns: 1fr 1fr;
    gap: 8px;
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }

  .brand-card {
    padding: 20px;
  }
}