/* ==========================================================================
   阿达西 (Adaxi) - 商务极简现代 CSS 设计系统 (原生 0 依赖)
   Business Minimalist Style & CSS Keyframes Animations
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. 设计 Token & 商务配色
   -------------------------------------------------------------------------- */
:root {
  /* 商务深色调色板 Business Dark Palette */
  --bg-dark: #0b0f19;
  --bg-card: rgba(17, 24, 39, 0.85);
  --bg-card-hover: rgba(24, 34, 53, 0.95);
  --bg-nav: rgba(11, 15, 25, 0.9);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-highlight: rgba(59, 130, 246, 0.4);

  /* 主主题色彩 Accents */
  --primary: #3b82f6;
  --primary-hover: #2563eb;
  --primary-light: #60a5fa;
  --accent-cyan: #06b6d4;
  --accent-emerald: #10b981;
  --accent-amber: #f59e0b;
  
  /* 渐变 Gradients */
  --grad-primary: linear-gradient(135deg, #2563eb 0%, #4f46e5 50%, #7c3aed 100%);
  --grad-hero: radial-gradient(circle at 70% 20%, rgba(59, 130, 246, 0.18) 0%, rgba(11, 15, 25, 0) 65%);
  --grad-card: linear-gradient(180deg, rgba(255, 255, 255, 0.03) 0%, rgba(255, 255, 255, 0) 100%);
  --grad-glow: radial-gradient(circle at 50% 50%, rgba(59, 130, 246, 0.15), transparent 70%);
  
  /* 文本颜色 Text */
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  
  /* 尺寸 & 边距 Spacing & Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;
  
  /* 阴影 & 模糊 Shadows */
  --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.25);
  --shadow-glow: 0 0 35px rgba(59, 130, 246, 0.2);
  --backdrop-blur: blur(16px);
  
  /* 字体 Typography */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --transition-fast: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* --------------------------------------------------------------------------
   2. 通用 Reset & 基础样式
   -------------------------------------------------------------------------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  background-color: var(--bg-dark);
  background-image: var(--grad-hero);
  background-attachment: fixed;
  color: var(--text-main);
  font-family: var(--font-family);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 5rem 0;
}

@media (max-width: 768px) {
  .section {
    padding: 3.5rem 0;
  }
}

/* --------------------------------------------------------------------------
   3. 核心按钮 CTA Button Standard
   -------------------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  padding: 0.85rem 1.85rem;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  transition: var(--transition-fast);
  cursor: pointer;
  border: 1px solid transparent;
  text-align: center;
  white-space: nowrap;
}

.btn-primary {
  background: var(--grad-primary);
  color: #ffffff;
  box-shadow: 0 4px 20px rgba(37, 99, 235, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(59, 130, 246, 0.45);
  filter: brightness(1.08);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
  border-color: var(--border-color);
  backdrop-filter: var(--backdrop-blur);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--border-highlight);
  transform: translateY(-2px);
}

.btn-block {
  width: 100%;
}

.btn-lg {
  padding: 1rem 2.25rem;
  font-size: 1.05rem;
}

/* --------------------------------------------------------------------------
   4. 商务页眉与导航目录 Header & Navigation Menu
   -------------------------------------------------------------------------- */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: var(--bg-nav);
  backdrop-filter: var(--backdrop-blur);
  border-bottom: 1px solid var(--border-color);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4.5rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #ffffff;
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: var(--grad-primary);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 900;
  font-size: 1.15rem;
  box-shadow: 0 2px 12px rgba(37, 99, 235, 0.4);
}

.logo-badge {
  font-size: 0.72rem;
  padding: 0.15rem 0.55rem;
  border-radius: var(--radius-full);
  background: rgba(6, 182, 212, 0.15);
  color: var(--accent-cyan);
  border: 1px solid rgba(6, 182, 212, 0.3);
  font-weight: 600;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2.25rem;
  list-style: none;
}

.nav-links a {
  font-size: 0.95rem;
  color: var(--text-muted);
  font-weight: 500;
  transition: var(--transition-fast);
}

.nav-links a:hover {
  color: var(--primary-light);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* --------------------------------------------------------------------------
   5. 商务左右分布 Hero Section + 动态图卡 (Keyframe Animations)
   -------------------------------------------------------------------------- */
.hero {
  padding-top: 8.5rem;
  padding-bottom: 5.5rem;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 3.5rem;
  align-items: center;
}

.hero-content {
  text-align: left;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 1rem;
  border-radius: var(--radius-full);
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: var(--primary-light);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
}

.hero-title {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.025em;
  margin-bottom: 1.25rem;
}

.text-gradient {
  background: linear-gradient(135deg, #60a5fa 0%, #3b82f6 50%, #a855f7 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-bottom: 2.25rem;
  line-height: 1.65;
}

.hero-buttons {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  margin-bottom: 2.5rem;
}

.hero-trust-badges {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.badge-item {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.badge-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-emerald);
}

/* --------------------------------------------------------------------------
   动态图卡 (Pure CSS Floating Dashboard & Animation)
   -------------------------------------------------------------------------- */
.hero-visual {
  position: relative;
}

.dynamic-card {
  background: var(--bg-card);
  border: 1px solid var(--border-highlight);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.4), var(--shadow-glow);
  backdrop-filter: var(--backdrop-blur);
  position: relative;
  overflow: hidden;
  animation: card-float 6s ease-in-out infinite alternate;
}

@keyframes card-float {
  0% { transform: translateY(0px); }
  100% { transform: translateY(-12px); }
}

.card-header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  margin-bottom: 1.25rem;
}

.card-title-group {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.live-pulse {
  width: 10px;
  height: 10px;
  background: var(--accent-emerald);
  border-radius: 50%;
  position: relative;
  box-shadow: 0 0 10px var(--accent-emerald);
}

.live-pulse::after {
  content: "";
  position: absolute;
  top: -4px;
  left: -4px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 2px solid var(--accent-emerald);
  animation: pulse-ring 1.8s cubic-bezier(0.215, 0.61, 0.355, 1) infinite;
}

@keyframes pulse-ring {
  0% { transform: scale(0.5); opacity: 1; }
  100% { transform: scale(1.6); opacity: 0; }
}

.card-status-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: #ffffff;
}

.card-badge-live {
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-full);
  background: rgba(16, 185, 129, 0.15);
  color: var(--accent-emerald);
  border: 1px solid rgba(16, 185, 129, 0.3);
  font-weight: 600;
}

.speed-meter {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 1.25rem;
  background: rgba(255, 255, 255, 0.03);
  padding: 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.speed-val {
  font-size: 2.25rem;
  font-weight: 900;
  color: #ffffff;
  line-height: 1;
}

.speed-unit {
  font-size: 0.9rem;
  color: var(--primary-light);
  font-weight: 600;
}

.ping-tag {
  font-size: 0.85rem;
  color: var(--accent-emerald);
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.3rem;
}

.progress-bar-container {
  height: 6px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: 1.5rem;
  position: relative;
}

.progress-bar-fill {
  height: 100%;
  width: 88%;
  background: linear-gradient(90deg, #3b82f6, #06b6d4, #10b981);
  border-radius: var(--radius-full);
  position: relative;
  animation: speed-shine 2.5s ease-in-out infinite;
}

@keyframes speed-shine {
  0% { width: 75%; }
  50% { width: 94%; }
  100% { width: 75%; }
}

.node-status-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.node-status-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1rem;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  transition: var(--transition-fast);
}

.node-status-item:hover {
  background: rgba(59, 130, 246, 0.1);
  border-color: var(--primary-light);
}

.node-name {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  color: var(--text-main);
}

.node-ms {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--accent-emerald);
}

.floating-pill-1 {
  position: absolute;
  top: -15px;
  right: -15px;
  background: var(--grad-primary);
  color: #fff;
  padding: 0.4rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 700;
  box-shadow: 0 4px 15px rgba(37, 99, 235, 0.4);
  animation: float-pill-1 4s ease-in-out infinite alternate;
}

@keyframes float-pill-1 {
  0% { transform: translate(0, 0); }
  100% { transform: translate(-6px, -10px); }
}

.floating-pill-2 {
  position: absolute;
  bottom: -15px;
  left: -15px;
  background: rgba(16, 185, 129, 0.9);
  color: #fff;
  padding: 0.4rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 700;
  box-shadow: 0 4px 15px rgba(16, 185, 129, 0.4);
  animation: float-pill-2 5s ease-in-out infinite alternate;
}

@keyframes float-pill-2 {
  0% { transform: translate(0, 0); }
  100% { transform: translate(8px, 8px); }
}

/* --------------------------------------------------------------------------
   6. 标题通用 Section Header
   -------------------------------------------------------------------------- */
.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 3.5rem auto;
}

.section-tag {
  color: var(--primary-light);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.5rem;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 0.75rem;
}

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

/* --------------------------------------------------------------------------
   7. 核心优势 (3个图文卡片) Core Advantages
   -------------------------------------------------------------------------- */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.feature-card {
  background: var(--bg-card);
  background-image: var(--grad-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.25rem 1.75rem;
  transition: var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--grad-primary);
  opacity: 0;
  transition: var(--transition-fast);
}

.feature-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-highlight);
  background: var(--bg-card-hover);
  box-shadow: var(--shadow-glow);
}

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

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary-light);
  margin-bottom: 1.5rem;
}

.feature-icon svg {
  width: 28px;
  height: 28px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.feature-title {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: #ffffff;
}

.feature-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   8. 流媒体与 AI 支持图卡 Streaming & AI Section
   -------------------------------------------------------------------------- */
.app-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 1.25rem;
  margin-top: 2rem;
}

.app-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem 1rem;
  text-align: center;
  transition: var(--transition-fast);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
}

.app-card:hover {
  border-color: var(--accent-cyan);
  transform: translateY(-4px);
  background: var(--bg-card-hover);
}

.app-badge {
  font-size: 0.75rem;
  padding: 0.15rem 0.5rem;
  border-radius: var(--radius-full);
  background: rgba(16, 185, 129, 0.15);
  color: var(--accent-emerald);
  border: 1px solid rgba(16, 185, 129, 0.3);
  font-weight: 600;
}

.app-icon-wrap {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1.2rem;
  color: #fff;
}

.icon-netflix { background: #E50914; }
.icon-youtube { background: #FF0000; }
.icon-disney { background: linear-gradient(135deg, #021B79, #0575E6); }
.icon-chatgpt { background: #10a37f; }
.icon-claude { background: #d97706; }
.icon-midjourney { background: #5865F2; }
.icon-tiktok { background: #000000; border: 1px solid rgba(255,255,255,0.2); }
.icon-deepseek { background: #3b82f6; }

.app-name {
  font-weight: 700;
  font-size: 1.05rem;
  color: #ffffff;
}

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

/* --------------------------------------------------------------------------
   9. 价格表 Pricing Table
   -------------------------------------------------------------------------- */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem 2rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition-fast);
  position: relative;
}

.pricing-card.popular {
  border-color: var(--primary);
  background: rgba(22, 32, 54, 0.95);
  box-shadow: 0 0 40px rgba(59, 130, 246, 0.25);
  transform: scale(1.03);
}

.popular-tag {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--grad-primary);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.25rem 1.1rem;
  border-radius: var(--radius-full);
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.pricing-card:hover {
  border-color: var(--border-highlight);
  transform: translateY(-4px);
}

.pricing-card.popular:hover {
  transform: scale(1.03) translateY(-4px);
}

.plan-name {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.plan-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  min-height: 2.5rem;
}

.plan-price {
  display: flex;
  align-items: baseline;
  gap: 0.25rem;
  margin-bottom: 0.3rem;
}

.price-currency {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent-cyan);
}

.price-amount {
  font-size: 3rem;
  font-weight: 900;
  color: #ffffff;
  line-height: 1;
}

.price-period {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.price-note {
  font-size: 0.78rem;
  color: var(--accent-emerald);
  margin-bottom: 1.5rem;
  font-weight: 600;
}

.plan-features {
  list-style: none;
  margin-bottom: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.9rem;
  color: var(--text-main);
}

.check-icon {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: rgba(16, 185, 129, 0.2);
  color: var(--accent-emerald);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: bold;
  flex-shrink: 0;
}

/* --------------------------------------------------------------------------
   10. SEO 9大文章图卡板块 (SEO Articles Grid Section Below Pricing)
   -------------------------------------------------------------------------- */
.article-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.article-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-highlight);
  background: var(--bg-card-hover);
  box-shadow: var(--shadow-glow);
}

.article-tag {
  display: inline-block;
  font-size: 0.75rem;
  padding: 0.2rem 0.65rem;
  border-radius: var(--radius-full);
  background: rgba(59, 130, 246, 0.15);
  color: var(--primary-light);
  border: 1px solid rgba(59, 130, 246, 0.3);
  font-weight: 600;
  margin-bottom: 0.85rem;
  width: fit-content;
}

.article-card.featured-brand {
  border-color: rgba(6, 182, 212, 0.4);
  background: linear-gradient(180deg, rgba(6, 182, 212, 0.08) 0%, rgba(17, 24, 39, 0.85) 100%);
}

.article-card.featured-brand .article-tag {
  background: rgba(6, 182, 212, 0.2);
  color: var(--accent-cyan);
  border-color: rgba(6, 182, 212, 0.4);
}

.article-title {
  font-size: 1.12rem;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.4;
  margin-bottom: 0.75rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-excerpt {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.55;
  margin-bottom: 1.25rem;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-footer-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.78rem;
  color: var(--text-dim);
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 0.85rem;
  margin-top: auto;
}

.article-link-btn {
  color: var(--primary-light);
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

.article-link-btn:hover {
  color: #ffffff;
}

/* --------------------------------------------------------------------------
   11. 用户评价 Testimonials
   -------------------------------------------------------------------------- */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.review-stars {
  color: var(--accent-amber);
  margin-bottom: 0.75rem;
  font-size: 0.9rem;
}

.review-content {
  font-size: 0.95rem;
  color: var(--text-main);
  line-height: 1.6;
  margin-bottom: 1.25rem;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--grad-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #fff;
  font-size: 0.9rem;
}

.author-info h4 {
  font-size: 0.95rem;
  font-weight: 700;
}

.author-info p {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   12. 常见问题解答 FAQ Accordion
   -------------------------------------------------------------------------- */
.faq-wrap {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: var(--transition-fast);
}

.faq-item[open] {
  border-color: var(--border-highlight);
  background: var(--bg-card-hover);
}

.faq-summary {
  padding: 1.25rem 1.5rem;
  font-size: 1.05rem;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

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

.faq-summary::after {
  content: "+";
  font-size: 1.3rem;
  font-weight: 400;
  color: var(--primary-light);
  transition: transform 0.25s ease;
}

.faq-item[open] .faq-summary::after {
  content: "−";
  transform: rotate(180deg);
}

.faq-content {
  padding: 0 1.5rem 1.25rem 1.5rem;
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  margin-top: 0.25rem;
  padding-top: 1rem;
}

/* --------------------------------------------------------------------------
   13. 极简页脚 Footer (Strictly 4 Links Only opening in new page)
   -------------------------------------------------------------------------- */
.footer {
  border-top: 1px solid var(--border-color);
  background: #070a12;
  padding: 3.5rem 0 2rem 0;
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2.5rem;
  list-style: none;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.footer-nav a {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-main);
  transition: var(--transition-fast);
}

.footer-nav a:hover {
  color: var(--primary-light);
}

.footer-copyright {
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-dim);
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 1.5rem;
}

/* --------------------------------------------------------------------------
   14. 独立子页面 Layout
   -------------------------------------------------------------------------- */
.page-header {
  padding-top: 8rem;
  padding-bottom: 3rem;
  text-align: center;
  background: radial-gradient(circle at 50% 0%, rgba(59, 130, 246, 0.15) 0%, rgba(11, 15, 25, 0) 70%);
}

.page-title {
  font-size: 2.75rem;
  font-weight: 800;
  margin-bottom: 1rem;
}

.page-subtitle {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto;
}

.content-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 3rem;
  margin-bottom: 4rem;
}

.content-body {
  color: var(--text-muted);
  font-size: 1rem;
  line-height: 1.8;
}

.content-body h2 {
  color: var(--text-main);
  font-size: 1.5rem;
  font-weight: 700;
  margin: 2rem 0 1rem 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.content-body h2::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 1.2rem;
  background: var(--primary);
  border-radius: 2px;
}

.content-body h2:first-child {
  margin-top: 0;
}

.content-body p {
  margin-bottom: 1.25rem;
}

.content-body ul {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}

.content-body li {
  margin-bottom: 0.5rem;
}

.node-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.25rem;
  margin: 1.5rem 0;
}

.node-card {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.25rem;
}

.node-region {
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.3rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.node-ping {
  font-size: 0.75rem;
  color: var(--accent-emerald);
  font-weight: 600;
}

/* --------------------------------------------------------------------------
   15. 移动端响应式 (Mobile First Breakpoints)
   -------------------------------------------------------------------------- */
@media (max-width: 992px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 3rem;
  }

  .hero-content {
    text-align: center;
  }

  .hero-title {
    font-size: 2.4rem;
  }

  .hero-buttons {
    justify-content: center;
  }

  .hero-trust-badges {
    justify-content: center;
  }
  
  .grid-3, .pricing-grid, .article-grid, .reviews-grid {
    grid-template-columns: repeat(1, 1fr);
  }
  
  .pricing-card.popular {
    transform: none;
  }
  
  .pricing-card.popular:hover {
    transform: translateY(-4px);
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  
  .hero {
    padding-top: 6.5rem;
    padding-bottom: 3rem;
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .hero-subtitle {
    font-size: 1rem;
  }
  
  .hero-buttons {
    flex-direction: column;
    width: 100%;
  }
  
  .hero-buttons .btn {
    width: 100%;
  }
  
  .content-card {
    padding: 1.5rem;
  }
  
  .footer-nav {
    flex-direction: column;
    gap: 1.25rem;
  }
}