/* ==========================================================================
   MESL 极速网络加速服务 - 原生高性能样式表 (浅色优雅风格，0 外部依赖，秒开加载)
   ========================================================================== */

:root {
  --bg-primary: #f8fafc;
  --bg-secondary: #f1f5f9;
  --bg-card: #ffffff;
  --bg-card-hover: #ffffff;
  --border-color: #e2e8f0;
  --border-highlight: rgba(99, 102, 241, 0.4);
  
  --primary: #4f46e5;
  --primary-light: #6366f1;
  --primary-glow: rgba(99, 102, 241, 0.2);
  --secondary: #0284c7;
  --accent: #ec4899;
  
  --text-main: #0f172a;
  --text-muted: #64748b;
  --text-sub: #334155;
  
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;
  
  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --container-width: 1200px;
}

/* 全局重置与基础设定 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-stack);
  background-color: var(--bg-primary);
  color: var(--text-main);
  scroll-behavior: smooth;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  overflow-x: hidden;
  background-color: var(--bg-primary);
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(99, 102, 241, 0.08) 0%, transparent 40%),
    radial-gradient(circle at 85% 65%, rgba(2, 132, 199, 0.06) 0%, transparent 45%),
    radial-gradient(circle at 50% 90%, rgba(236, 72, 153, 0.04) 0%, transparent 50%);
  background-attachment: fixed;
}

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

ul, ol {
  list-style: none;
}

img, svg {
  vertical-align: middle;
}

.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* 按钮通用组件 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  padding: 12px 28px;
  border-radius: var(--radius-full);
  font-size: 1rem;
  cursor: pointer;
  border: 1px solid transparent;
  gap: 8px;
  transition: var(--transition);
  min-height: 48px;
  text-align: center;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, #4f46e5 0%, #6366f1 50%, #0284c7 100%);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(79, 70, 229, 0.25);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(79, 70, 229, 0.35);
  filter: brightness(1.05);
}

.btn-secondary {
  background: #ffffff;
  color: var(--text-main);
  border: 1px solid #cbd5e1;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

.btn-secondary:hover {
  background: #f8fafc;
  border-color: #94a3b8;
  transform: translateY(-2px);
}

.btn-block {
  width: 100%;
}

/* 顶部导航栏 (浅色背景 + 微磨砂模糊) */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.03);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  color: var(--text-main);
}

.logo-badge {
  font-size: 0.72rem;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background: #eef2ff;
  color: #4f46e5;
  border: 1px solid #c7d2fe;
  font-weight: 600;
}

.nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
}

.nav-link:hover {
  color: var(--primary);
}

.nav-link-highlight {
  color: var(--primary) !important;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.nav-badge-hot {
  font-size: 0.65rem;
  padding: 1px 6px;
  background: #fce7f3;
  color: var(--accent);
  border: 1px solid #fbcfe8;
  border-radius: var(--radius-full);
  line-height: 1.2;
}

.header-cta .btn {
  padding: 8px 20px;
  min-height: 40px;
  font-size: 0.9rem;
}

/* 主视觉区 (Hero Section) */
.hero {
  padding: 80px 0 50px;
  text-align: center;
  position: relative;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: #eef2ff;
  border: 1px solid #c7d2fe;
  border-radius: var(--radius-full);
  color: #4338ca;
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero-tag-dot {
  width: 8px;
  height: 8px;
  background-color: #10b981;
  border-radius: 50%;
  box-shadow: 0 0 8px #10b981;
}

.hero-title {
  font-size: 3.1rem;
  font-weight: 850;
  line-height: 1.25;
  margin-bottom: 20px;
  letter-spacing: -1px;
  color: var(--text-main);
}

.gradient-text {
  background: linear-gradient(135deg, #1e1b4b 0%, #4338ca 50%, #0284c7 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-sub {
  font-size: 1.18rem;
  color: var(--text-muted);
  max-width: 780px;
  margin: 0 auto 36px;
  font-weight: 400;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 40px;
}

/* AI 算力精美云海主视觉画卷 (浅色微质感边框) */
.hero-showcase {
  max-width: 980px;
  margin: 0 auto 48px;
  position: relative;
}

.hero-image-card {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid #cbd5e1;
  background: #ffffff;
  box-shadow: 
    0 20px 40px -15px rgba(0, 0, 0, 0.08),
    0 0 30px rgba(99, 102, 241, 0.12);
  transition: var(--transition);
}

.hero-image-card:hover {
  transform: translateY(-4px);
  box-shadow: 
    0 24px 48px -12px rgba(0, 0, 0, 0.12),
    0 0 40px rgba(99, 102, 241, 0.2);
}

.hero-clouds-img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.hero-image-card:hover .hero-clouds-img {
  transform: scale(1.02);
}

.hero-image-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 20px 24px;
  background: linear-gradient(180deg, transparent 0%, rgba(15, 23, 42, 0.75) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-image-badge {
  font-size: 0.95rem;
  font-weight: 600;
  color: #ffffff;
  background: rgba(15, 23, 42, 0.7);
  backdrop-filter: blur(8px);
  padding: 6px 18px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(255, 255, 255, 0.2);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.hero-trust {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 24px;
  padding-top: 24px;
  border-top: 1px dashed #cbd5e1;
  color: var(--text-sub);
  font-size: 0.92rem;
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 8px;
}

.trust-item svg {
  color: #10b981;
}

/* 模块通用结构 */
.section {
  padding: 80px 0;
}

.section-alt {
  background: #f1f5f9;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 52px;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 14px;
  color: var(--text-main);
}

.section-desc {
  color: var(--text-muted);
  font-size: 1.05rem;
}

/* 优势卡片网格 (浅色纯白卡片) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  transition: var(--transition);
  position: relative;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.feature-card:hover {
  transform: translateY(-5px);
  border-color: #c7d2fe;
  box-shadow: 0 12px 24px -4px rgba(79, 70, 229, 0.12);
}

.feature-icon-box {
  width: 54px;
  height: 54px;
  border-radius: var(--radius-md);
  background: #eef2ff;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  border: 1px solid #c7d2fe;
  color: var(--primary);
}

.feature-card h3 {
  font-size: 1.25rem;
  margin-bottom: 12px;
  font-weight: 700;
  color: var(--text-main);
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.94rem;
  line-height: 1.65;
}

/* 流媒体与 AI 支持模块 */
.unlock-matrix {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}

.unlock-category {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  position: relative;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.unlock-category::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
}

.category-title {
  font-size: 1.45rem;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text-main);
}

.category-desc {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 24px;
}

.badge-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}

.badge-item {
  display: flex;
  align-items: center;
  gap: 10px;
  background: #f8fafc;
  padding: 12px 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-sub);
}

.badge-item svg {
  color: #10b981;
  flex-shrink: 0;
}

.badge-speed {
  margin-left: auto;
  font-size: 0.75rem;
  padding: 2px 6px;
  background: #d1fae5;
  color: #065f46;
  border-radius: 4px;
  font-weight: 600;
}

/* 价格套餐对比表 */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: stretch;
}

.pricing-card {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px 32px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: var(--transition);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.04);
}

.pricing-card:hover {
  transform: translateY(-6px);
  border-color: #c7d2fe;
  box-shadow: 0 16px 32px -4px rgba(79, 70, 229, 0.15);
}

.pricing-card.featured {
  background: #ffffff;
  border: 2px solid var(--primary-light);
  box-shadow: 0 12px 30px rgba(99, 102, 241, 0.18);
  transform: scale(1.03);
}

.pricing-card.featured:hover {
  transform: scale(1.03) translateY(-6px);
}

.pricing-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, var(--accent), var(--primary));
  color: #ffffff;
  padding: 4px 18px;
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.5px;
}

.plan-header {
  margin-bottom: 24px;
  text-align: center;
}

.plan-name {
  font-size: 1.45rem;
  font-weight: 800;
  margin-bottom: 6px;
  color: var(--text-main);
}

.plan-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.plan-price {
  margin: 20px 0 24px;
  text-align: center;
}

.price-currency {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--secondary);
  vertical-align: super;
}

.price-val {
  font-size: 3rem;
  font-weight: 850;
  line-height: 1;
  color: var(--text-main);
}

.price-period {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.plan-features {
  margin-bottom: 32px;
  flex-grow: 1;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
  font-size: 0.92rem;
  color: var(--text-sub);
}

.plan-features li svg {
  color: #10b981;
  flex-shrink: 0;
}

/* 用户评价 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 30px 26px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.review-stars {
  color: #f59e0b;
  margin-bottom: 16px;
  display: flex;
  gap: 4px;
}

.review-text {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--text-sub);
  margin-bottom: 20px;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid #f1f5f9;
  padding-top: 16px;
}

.author-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
  color: #ffffff;
}

.author-name {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--text-main);
}

.author-role {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* 常见问题解答 (FAQ) */
.faq-list {
  max-width: 840px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: var(--transition);
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.03);
}

.faq-item[open] {
  border-color: #c7d2fe;
  background: #fafbff;
}

.faq-question {
  padding: 20px 24px;
  font-size: 1.05rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
  color: var(--text-main);
}

.faq-question::-webkit-details-marker {
  display: none;
}

.faq-icon {
  transition: transform 0.25s ease;
  color: var(--primary);
}

.faq-item[open] .faq-icon {
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 24px 22px;
  color: var(--text-sub);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* CTA 转换 Banner */
.cta-banner {
  background: linear-gradient(135deg, #eef2ff 0%, #ecfeff 100%);
  border: 1px solid #c7d2fe;
  border-radius: var(--radius-lg);
  padding: 56px 40px;
  text-align: center;
  margin-top: 60px;
}

.cta-banner h2 {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--text-main);
}

.cta-banner p {
  color: var(--text-sub);
  font-size: 1.1rem;
  max-width: 650px;
  margin: 0 auto 32px;
}

/* 页脚 (浅色简洁) */
.footer {
  border-top: 1px solid var(--border-color);
  padding: 50px 0 40px;
  background: #f8fafc;
  margin-top: 80px;
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 48px;
  margin-bottom: 30px;
  flex-wrap: wrap;
}

.footer-link {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-sub);
  position: relative;
  padding: 6px 0;
}

.footer-link:hover {
  color: var(--primary);
}

.footer-copy {
  text-align: center;
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* 独立内页共用样式 */
.doc-page {
  padding: 60px 0 100px;
}

.doc-box {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 48px;
  max-width: 900px;
  margin: 0 auto;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.04);
}

.doc-header {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 24px;
  margin-bottom: 36px;
}

.doc-header h1 {
  font-size: 2.4rem;
  margin-bottom: 12px;
  color: var(--text-main);
}

.doc-header p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.doc-section {
  margin-bottom: 36px;
}

.doc-section h2 {
  font-size: 1.4rem;
  margin-bottom: 16px;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 10px;
}

.doc-section h2::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 18px;
  background: var(--primary);
  border-radius: 2px;
}

.doc-section p {
  color: var(--text-sub);
  line-height: 1.8;
  margin-bottom: 12px;
  font-size: 0.98rem;
}

.doc-section ul, .doc-section ol {
  padding-left: 20px;
  margin-bottom: 16px;
}

.doc-section ul li, .doc-section ol li {
  color: var(--text-sub);
  margin-bottom: 8px;
  line-height: 1.7;
}

.doc-section ul li {
  list-style-type: disc;
}

.highlight-box {
  background: #eef2ff;
  border-left: 4px solid var(--primary);
  padding: 18px 22px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 20px 0;
  color: #1e1b4b;
}

.warning-box {
  background: #fef2f2;
  border-left: 4px solid #ef4444;
  padding: 18px 22px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 20px 0;
  color: #991b1b;
}

/* 网站地图样式 */
.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.sitemap-card {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.03);
}

.sitemap-card h3 {
  font-size: 1.15rem;
  margin-bottom: 14px;
  color: var(--secondary);
}

.sitemap-card ul li {
  margin-bottom: 10px;
}

.sitemap-card ul li a {
  color: var(--text-sub);
}

.sitemap-card ul li a:hover {
  color: var(--primary);
  text-decoration: underline;
}

/* ==========================================================================
   高科技网格卡片 (浅色微质感 High-Tech Grid Cards)
   ========================================================================== */
.article-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin: 32px 0 48px;
}

.article-card {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  overflow: hidden;
  transition: var(--transition);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.article-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--primary), transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.article-card:hover {
  transform: translateY(-5px);
  border-color: #c7d2fe;
  box-shadow: 0 12px 24px -4px rgba(79, 70, 229, 0.12);
}

.article-card:hover::before {
  opacity: 1;
}

.article-card-badge {
  font-size: 0.75rem;
  font-weight: 600;
  color: #0369a1;
  background: #e0f2fe;
  border: 1px solid #bae6fd;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  display: inline-block;
  margin-bottom: 14px;
  align-self: flex-start;
}

.article-card-title {
  font-size: 1.08rem;
  font-weight: 700;
  line-height: 1.45;
  margin-bottom: 12px;
  color: var(--text-main);
  transition: var(--transition);
}

.article-card:hover .article-card-title {
  color: var(--primary);
}

.article-card-excerpt {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid #f1f5f9;
  padding-top: 14px;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.article-card-link {
  color: var(--secondary);
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.88rem;
}

.article-card:hover .article-card-link {
  color: var(--primary);
}

/* ==========================================================================
   响应式设计 (@media)
   ========================================================================== */
@media (max-width: 1024px) {
  .features-grid,
  .pricing-grid,
  .reviews-grid,
  .article-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .pricing-card.featured {
    transform: none;
  }
  
  .pricing-card.featured:hover {
    transform: translateY(-6px);
  }
  
  .hero-title {
    font-size: 2.6rem;
  }
}

@media (max-width: 768px) {
  .header-inner {
    height: 64px;
  }
  
  .nav {
    display: none;
  }
  
  .hero {
    padding: 50px 0 40px;
  }
  
  .hero-title {
    font-size: 2.1rem;
  }
  
  .hero-sub {
    font-size: 1rem;
  }
  
  .hero-actions {
    flex-direction: column;
    width: 100%;
  }
  
  .hero-actions .btn {
    width: 100%;
    min-height: 52px;
    font-size: 1.05rem;
  }
  
  .features-grid,
  .pricing-grid,
  .reviews-grid,
  .unlock-matrix,
  .sitemap-grid,
  .article-grid {
    grid-template-columns: 1fr;
  }
  
  .badge-grid {
    grid-template-columns: 1fr;
  }
  
  .section {
    padding: 50px 0;
  }
  
  .section-title {
    font-size: 1.8rem;
  }
  
  .pricing-card {
    padding: 30px 20px;
  }
  
  .footer-nav {
    flex-direction: column;
    gap: 20px;
  }
  
  .doc-box {
    padding: 28px 20px;
  }
  
  .doc-header h1 {
    font-size: 1.9rem;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.85rem;
  }
  
  .container {
    padding: 0 16px;
  }
  
  .btn {
    width: 100%;
  }
}