/* ==========================================================================
   COCODUCK VPN - Neo-Pop High-Contrast Yellow & Black Design System
   Hyper-saturated duckling yellow (#ffcc00), Obsidian black (#0d0d0d), Paper white
   Neo-brutalist offset flat tactile drop-shadows + Buoyant duck physics
   ========================================================================== */

:root {
  /* Neo-Pop Core Palette - Light Mode (Default) */
  --neo-yellow: #ffcc00;
  --neo-yellow-light: #fff5c0;
  --neo-yellow-glow: rgba(255, 204, 0, 0.45);
  
  --neo-black: #0d0d0d;
  --neo-black-soft: #1a1a1a;
  
  --bg-primary: #fdfaf0; /* Warm crisp off-white paper canvas */
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #fffdf5;
  --bg-glass: rgba(253, 250, 240, 0.92);
  
  --border-neo: #0d0d0d;
  --shadow-neo: #0d0d0d;
  --border-width: 2.5px;
  
  --text-primary: #0d0d0d;
  --text-secondary: #262626;
  --text-muted: #525252;
  --text-inverse: #ffffff;
  
  --accent-cyan: #00d2d3;
  --accent-magenta: #ff6b81;
  --accent-green: #10b981;
  
  --brand-gradient: linear-gradient(135deg, #ffcc00 0%, #ffaa00 100%);
  --brand-button-shadow: 4px 4px 0px #0d0d0d;
  --card-shadow: 4px 4px 0px #0d0d0d;
  --card-shadow-hover: 7px 7px 0px #0d0d0d;
  
  --font-sans: "Impact", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-full: 9999px;

  --transition-bounce: 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  --transition-fast: 0.15s ease;
  --transition-theme: background-color 0.25s ease, border-color 0.25s ease, color 0.25s ease, box-shadow 0.25s ease;
}

/* Dark Mode Overrides (Obsidian ink with punchy neo-yellow borders & glow) */
[data-theme="dark"] {
  --bg-primary: #0a0a0a;
  --bg-secondary: #141414;
  --bg-card: #141414;
  --bg-card-hover: #1c1c1c;
  --bg-glass: rgba(10, 10, 10, 0.92);

  --border-neo: #ffcc00;
  --shadow-neo: #ffcc00;

  --text-primary: #ffffff;
  --text-secondary: #e5e5e5;
  --text-muted: #a3a3a3;
  --text-inverse: #0a0a0a;

  --brand-button-shadow: 4px 4px 0px #ffcc00;
  --card-shadow: 4px 4px 0px #ffcc00;
  --card-shadow-hover: 7px 7px 0px #ffcc00;
}

/* ==========================================================================
   Base & Reset
   ========================================================================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: var(--transition-theme);
  overflow-x: hidden;
  background-image: radial-gradient(rgba(13, 13, 13, 0.04) 1px, transparent 1px);
  background-size: 24px 24px;
}

[data-theme="dark"] body {
  background-image: radial-gradient(rgba(255, 204, 0, 0.06) 1px, transparent 1px);
}

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

img, svg {
  vertical-align: middle;
  max-width: 100%;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

/* ==========================================================================
   Layout Containers & Headers
   ========================================================================== */
.container {
  width: 100%;
  max-width: 1220px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

.container-narrow {
  max-width: 900px;
}

.section {
  padding: 96px 0;
  position: relative;
  scroll-margin-top: 80px; /* Perfect anchor offset */
}

.section-alt {
  background-color: var(--bg-secondary);
  border-top: var(--border-width) solid var(--border-neo);
  border-bottom: var(--border-width) solid var(--border-neo);
}

.section-header {
  text-align: center;
  max-width: 820px;
  margin: 0 auto 60px;
}

/* Neo-Pop Badge */
.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  font-weight: 800;
  color: #0d0d0d;
  background: var(--neo-yellow);
  border: var(--border-width) solid var(--border-neo);
  box-shadow: 3px 3px 0px var(--shadow-neo);
  padding: 6px 18px;
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
  letter-spacing: 0.8px;
  text-transform: uppercase;
}

.section-title {
  font-size: 2.6rem;
  font-weight: 900;
  line-height: 1.2;
  color: var(--text-primary);
  margin-bottom: 18px;
  letter-spacing: -0.8px;
}

.section-desc {
  font-size: 1.15rem;
  color: var(--text-secondary);
  line-height: 1.65;
  font-weight: 500;
}

/* ==========================================================================
   Header & Navbar (With Smooth Anchor Transitions)
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: var(--bg-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: var(--border-width) solid var(--border-neo);
  transition: var(--transition-theme);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}

/* Brand Logo */
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}

.brand-logo-wrap {
  display: inline-flex;
  align-items: center;
  height: 42px;
}

.brand-logo-img {
  height: 40px;
  width: auto;
  display: block;
  object-fit: contain;
  transition: transform var(--transition-bounce);
}

.brand:hover .brand-logo-img {
  transform: rotate(-5deg) scale(1.08);
}

.brand-logo-light {
  display: block;
}

.brand-logo-dark {
  display: none;
}

[data-theme="dark"] .brand-logo-light {
  display: none;
}

[data-theme="dark"] .brand-logo-dark {
  display: block;
}

.brand-vpn-badge {
  font-size: 0.75rem;
  font-weight: 900;
  letter-spacing: 0.8px;
  background: var(--neo-yellow);
  color: #0d0d0d;
  border: 2px solid var(--border-neo);
  box-shadow: 2px 2px 0px var(--shadow-neo);
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  line-height: 1;
}

/* Navigation Links */
.nav-menu {
  display: flex;
  align-items: center;
  gap: 22px;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  position: relative;
  padding: 6px 4px;
  transition: color var(--transition-fast);
}

.nav-link:hover {
  color: #ff9900;
}

[data-theme="dark"] .nav-link:hover {
  color: var(--neo-yellow);
}

/* Special High-Lighted '推荐资讯' Nav Item */
.nav-link-news {
  background: var(--neo-yellow);
  color: #0d0d0d !important;
  border: 2px solid var(--border-neo);
  box-shadow: 2px 2px 0px var(--shadow-neo);
  padding: 4px 12px;
  border-radius: var(--radius-sm);
  font-weight: 800;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.nav-link-news:hover {
  transform: translate(-2px, -2px);
  box-shadow: 4px 4px 0px var(--shadow-neo);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* Neo-Pop Theme Toggle Button */
.theme-toggle-btn {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  color: var(--text-primary);
  box-shadow: 3px 3px 0px var(--shadow-neo);
  transition: all var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.theme-toggle-btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0px var(--shadow-neo);
}

.theme-toggle-btn:active {
  transform: translate(2px, 2px);
  box-shadow: 1px 1px 0px var(--shadow-neo);
}

.theme-icon-sun,
.theme-icon-moon {
  position: absolute;
  width: 22px;
  height: 22px;
  transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1), opacity 0.25s ease;
}

[data-theme="light"] .theme-icon-sun {
  transform: scale(1) rotate(0deg);
  opacity: 1;
  color: #d97706;
}

[data-theme="light"] .theme-icon-moon {
  transform: scale(0.3) rotate(90deg);
  opacity: 0;
  pointer-events: none;
}

[data-theme="dark"] .theme-icon-sun {
  transform: scale(0.3) rotate(-90deg);
  opacity: 0;
  pointer-events: none;
}

[data-theme="dark"] .theme-icon-moon {
  transform: scale(1) rotate(0deg);
  opacity: 1;
  color: var(--neo-yellow);
}

/* Mobile Nav Toggle */
.mobile-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  align-items: center;
  justify-content: center;
  color: var(--text-primary);
  border: var(--border-width) solid var(--border-neo);
  background: var(--bg-card);
  box-shadow: 3px 3px 0px var(--shadow-neo);
}

/* ==========================================================================
   Neo-Pop Buttons & CTA
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  font-size: 1rem;
  font-weight: 800;
  padding: 12px 26px;
  border-radius: var(--radius-md);
  border: var(--border-width) solid var(--border-neo);
  box-shadow: var(--brand-button-shadow);
  transition: all var(--transition-fast);
  text-align: center;
  white-space: nowrap;
  cursor: pointer;
  letter-spacing: 0.3px;
}

.btn:hover {
  transform: translate(-3px, -3px);
  box-shadow: 6px 6px 0px var(--shadow-neo);
}

.btn:active {
  transform: translate(2px, 2px);
  box-shadow: 1px 1px 0px var(--shadow-neo);
}

/* Yellow primary button */
.btn-primary {
  background: var(--neo-yellow);
  color: #0d0d0d;
}

.btn-primary:hover {
  background: #ffd633;
  color: #0d0d0d;
}

/* Black/Dark Button */
.btn-dark {
  background: #0d0d0d;
  color: #ffffff;
}

[data-theme="dark"] .btn-dark {
  background: #ffffff;
  color: #0d0d0d;
  border-color: var(--neo-yellow);
}

.btn-dark:hover {
  background: #262626;
  color: #ffffff;
}

/* Outline button */
.btn-outline {
  background: var(--bg-card);
  color: var(--text-primary);
}

.btn-outline:hover {
  background: var(--neo-yellow-light);
  color: #0d0d0d;
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.15rem;
  font-weight: 900;
  border-radius: var(--radius-lg);
}

.btn-sm {
  padding: 8px 18px;
  font-size: 0.88rem;
  box-shadow: 3px 3px 0px var(--shadow-neo);
}

.btn-block {
  width: 100%;
}

/* ==========================================================================
   Hero Section (Neo-Brutalist & "STABLE BEYOND BELIEF")
   ========================================================================== */
.hero-section {
  padding: 80px 0 100px;
  position: relative;
  overflow: hidden;
}

.hero-box {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  box-shadow: 8px 8px 0px var(--shadow-neo);
  border-radius: var(--radius-lg);
  padding: 60px 48px;
  position: relative;
  text-align: center;
}

.hero-stamp {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: #0d0d0d;
  color: var(--neo-yellow);
  border: 2px solid var(--neo-yellow);
  padding: 6px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  font-weight: 900;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  margin-bottom: 24px;
  transform: rotate(-1.5deg);
  box-shadow: 3px 3px 0px var(--shadow-neo);
}

[data-theme="dark"] .hero-stamp {
  background: var(--neo-yellow);
  color: #0d0d0d;
  border-color: #0d0d0d;
}

.hero-title {
  font-size: 3.8rem;
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: -1.5px;
  margin-bottom: 22px;
  color: var(--text-primary);
}

.hero-title-highlight {
  background: var(--neo-yellow);
  color: #0d0d0d;
  padding: 2px 14px;
  border-radius: var(--radius-sm);
  border: 2.5px solid var(--border-neo);
  box-shadow: 4px 4px 0px var(--shadow-neo);
  display: inline-block;
  transform: rotate(0.8deg);
  margin-top: 6px;
}

.hero-subtitle {
  font-size: 1.3rem;
  line-height: 1.7;
  color: var(--text-secondary);
  max-width: 820px;
  margin: 0 auto 38px;
  font-weight: 500;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
  margin-bottom: 40px;
}

.hero-guarantee {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 28px;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-secondary);
  flex-wrap: wrap;
  padding-top: 24px;
  border-top: 2px dashed var(--border-neo);
}

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

.hero-guarantee-item svg {
  color: var(--accent-green);
  stroke-width: 3;
}

/* Hero Stats Neo-Grid */
.hero-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 40px;
}

.stat-item {
  background: var(--bg-secondary);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-md);
  padding: 24px 16px;
  text-align: center;
  box-shadow: 4px 4px 0px var(--shadow-neo);
  transition: transform var(--transition-bounce);
}

.stat-item:hover {
  transform: translateY(-4px);
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 900;
  line-height: 1;
  color: var(--text-primary);
  margin-bottom: 8px;
  letter-spacing: -1px;
}

.stat-label {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-muted);
}

/* ==========================================================================
   Buoyant Duck Physics Micro-Interactions (Floating Cards)
   ========================================================================== */
.buoyant-card {
  transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.25s ease;
  will-change: transform;
}

.buoyant-card:hover {
  transform: translateY(-8px) rotate(-1.2deg);
  box-shadow: var(--card-shadow-hover);
}

.buoyant-card:nth-child(even):hover {
  transform: translateY(-8px) rotate(1.2deg);
}

/* 3 Core Advantage Cards */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

.feature-card {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-lg);
  padding: 38px 30px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  position: relative;
}

.feature-icon-box {
  width: 68px;
  height: 68px;
  border-radius: var(--radius-md);
  background: var(--neo-yellow);
  border: var(--border-width) solid var(--border-neo);
  box-shadow: 3px 3px 0px var(--shadow-neo);
  color: #0d0d0d;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
}

.feature-title {
  font-size: 1.45rem;
  font-weight: 900;
  margin-bottom: 14px;
  color: var(--text-primary);
}

.feature-desc {
  font-size: 1.02rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 24px;
  flex-grow: 1;
}

.feature-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: auto;
}

.feature-pill {
  font-size: 0.82rem;
  font-weight: 800;
  color: #0d0d0d;
  background: var(--neo-yellow-light);
  border: 1.5px solid var(--border-neo);
  padding: 5px 12px;
  border-radius: var(--radius-sm);
}

/* ==========================================================================
   Speed Benchmark: Analog Rotary Dial Component
   Interactive analog rotary dial with low-ping nodes filter
   ========================================================================== */
.rotary-benchmark-box {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-lg);
  padding: 44px;
  box-shadow: 8px 8px 0px var(--shadow-neo);
  margin-top: 40px;
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 40px;
  align-items: center;
}

.dial-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.rotary-dial-wrap {
  position: relative;
  width: 220px;
  height: 220px;
  margin-bottom: 20px;
  user-select: none;
}

.rotary-bezel {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  border: 4px solid var(--border-neo);
  background: var(--bg-secondary);
  box-shadow: 5px 5px 0px var(--shadow-neo), inset 0 0 15px rgba(0,0,0,0.1);
  position: relative;
  cursor: grab;
  display: flex;
  align-items: center;
  justify-content: center;
}

.rotary-knob {
  width: 130px;
  height: 130px;
  border-radius: 50%;
  background: var(--neo-yellow);
  border: 3.5px solid var(--border-neo);
  box-shadow: 3px 3px 0px var(--shadow-neo);
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.rotary-knob-indicator {
  position: absolute;
  top: 10px;
  width: 6px;
  height: 22px;
  background: #0d0d0d;
  border-radius: var(--radius-full);
}

.rotary-center-cap {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: #0d0d0d;
  color: var(--neo-yellow);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 900;
  font-size: 0.75rem;
  letter-spacing: 0.5px;
}

.dial-instructions {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text-muted);
}

.dial-node-results {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.benchmark-card {
  background: var(--bg-secondary);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-md);
  padding: 18px 22px;
  box-shadow: 3px 3px 0px var(--shadow-neo);
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.benchmark-card.active-node {
  border-color: #ff9900;
  background: var(--neo-yellow-light);
  transform: translateX(6px);
  box-shadow: 5px 5px 0px var(--shadow-neo);
}

[data-theme="dark"] .benchmark-card.active-node {
  background: #242410;
  border-color: var(--neo-yellow);
}

.node-flag-title {
  display: flex;
  align-items: center;
  gap: 12px;
}

.node-code {
  font-size: 1.1rem;
  font-weight: 900;
  color: var(--text-primary);
}

.node-route-type {
  font-size: 0.8rem;
  font-weight: 800;
  background: #0d0d0d;
  color: #ffffff;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
}

[data-theme="dark"] .node-route-type {
  background: var(--neo-yellow);
  color: #0d0d0d;
}

.node-speed-metrics {
  display: flex;
  align-items: center;
  gap: 18px;
}

.ping-tag {
  font-size: 1.25rem;
  font-weight: 900;
  color: var(--accent-green);
  display: flex;
  align-items: center;
  gap: 4px;
}

.throughput-tag {
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--text-secondary);
}

/* ==========================================================================
   Streaming Showcase Cards
   ========================================================================== */
.stream-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(270px, 1fr));
  gap: 24px;
}

.stream-card {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-lg);
  padding: 26px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
}

.stream-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
}

.stream-badge-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  border: 2px solid var(--border-neo);
  box-shadow: 2px 2px 0px var(--shadow-neo);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 900;
  font-size: 1.15rem;
  color: #fff;
}

.stream-badge-netflix { background: #e50914; }
.stream-badge-youtube { background: #ff0000; }
.stream-badge-disney { background: #002d72; }
.stream-badge-max { background: #002be7; }
.stream-badge-tiktok { background: #000000; }
.stream-badge-spotify { background: #1db954; }

.stream-info h4 {
  font-size: 1.18rem;
  font-weight: 900;
  color: var(--text-primary);
}

.stream-info span {
  font-size: 0.82rem;
  color: var(--accent-green);
  font-weight: 800;
}

.stream-desc {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.55;
  margin-bottom: 16px;
  flex-grow: 1;
}

.stream-features {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-muted);
}

/* ==========================================================================
   AI Support Showcase
   ========================================================================== */
.ai-banner {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-lg);
  padding: 44px;
  box-shadow: 8px 8px 0px var(--shadow-neo);
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: center;
}

.ai-content h3 {
  font-size: 2.1rem;
  font-weight: 900;
  margin-bottom: 18px;
  color: var(--text-primary);
  line-height: 1.25;
}

.ai-content p {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-bottom: 26px;
  line-height: 1.7;
}

.ai-pill-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 30px;
}

.ai-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--neo-yellow);
  color: #0d0d0d;
  border: 2px solid var(--border-neo);
  box-shadow: 2px 2px 0px var(--shadow-neo);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.92rem;
  font-weight: 900;
}

.ai-cards-matrix {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.ai-mini-card {
  background: var(--bg-secondary);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-md);
  padding: 22px;
  box-shadow: 3px 3px 0px var(--shadow-neo);
  transition: transform var(--transition-fast);
}

.ai-mini-card:hover {
  transform: translateY(-3px);
  box-shadow: 5px 5px 0px var(--shadow-neo);
}

.ai-mini-card h5 {
  font-size: 1.05rem;
  font-weight: 900;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.ai-mini-card p {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* ==========================================================================
   Real Market Pricing Comparison Table
   ========================================================================== */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-lg);
  padding: 44px 32px;
  display: flex;
  flex-direction: column;
  position: relative;
  box-shadow: var(--card-shadow);
  transition: all var(--transition-bounce);
}

.pricing-card.featured {
  background: var(--neo-yellow-light);
  border-width: 3.5px;
  box-shadow: 8px 8px 0px var(--shadow-neo);
  transform: scale(1.02);
  z-index: 2;
}

[data-theme="dark"] .pricing-card.featured {
  background: #1c1c14;
  border-color: var(--neo-yellow);
}

.featured-ribbon {
  position: absolute;
  top: -16px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--neo-yellow);
  color: #0d0d0d;
  font-size: 0.82rem;
  font-weight: 900;
  padding: 6px 20px;
  border-radius: var(--radius-sm);
  border: 2px solid var(--border-neo);
  box-shadow: 2px 2px 0px var(--shadow-neo);
  letter-spacing: 0.8px;
  text-transform: uppercase;
}

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

.pricing-name {
  font-size: 1.55rem;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.pricing-desc {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-muted);
}

.pricing-price-wrap {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 4px;
  margin-bottom: 26px;
  padding-bottom: 24px;
  border-bottom: 2px dashed var(--border-neo);
}

.pricing-currency {
  font-size: 1.6rem;
  font-weight: 900;
  color: var(--text-primary);
}

.pricing-amount {
  font-size: 3.4rem;
  font-weight: 900;
  line-height: 1;
  color: var(--text-primary);
  letter-spacing: -1.5px;
}

.pricing-period {
  font-size: 1rem;
  font-weight: 800;
  color: var(--text-muted);
}

.pricing-features {
  margin-bottom: 34px;
  flex-grow: 1;
}

.pricing-feature-item {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 14px;
}

.pricing-feature-item svg {
  color: var(--accent-green);
  stroke-width: 3;
  flex-shrink: 0;
}

/* ==========================================================================
   User Testimonials
   ========================================================================== */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.testimonial-card {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-lg);
  padding: 34px 28px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
}

.testimonial-stars {
  display: flex;
  gap: 4px;
  color: #ff9900;
  font-size: 1.2rem;
  margin-bottom: 18px;
}

.testimonial-text {
  font-size: 1rem;
  line-height: 1.68;
  color: var(--text-secondary);
  margin-bottom: 24px;
  flex-grow: 1;
  font-weight: 500;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 14px;
}

.author-avatar {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-sm);
  background: var(--neo-yellow);
  color: #0d0d0d;
  border: 2px solid var(--border-neo);
  box-shadow: 2px 2px 0px var(--shadow-neo);
  font-weight: 900;
  font-size: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.author-info h5 {
  font-size: 1.05rem;
  font-weight: 900;
  color: var(--text-primary);
}

.author-info span {
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--text-muted);
}

/* ==========================================================================
   FAQ Section (Accordion)
   ========================================================================== */
.faq-list {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.faq-item {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-md);
  box-shadow: 4px 4px 0px var(--shadow-neo);
  overflow: hidden;
  transition: transform var(--transition-fast);
}

.faq-question {
  padding: 22px 26px;
  font-size: 1.12rem;
  font-weight: 900;
  color: var(--text-primary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
  list-style: none;
}

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

.faq-icon {
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  color: var(--text-primary);
}

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

.faq-answer {
  padding: 0 26px 24px;
  font-size: 1.02rem;
  color: var(--text-secondary);
  line-height: 1.7;
  border-top: 2px dashed var(--border-neo);
  padding-top: 18px;
}

/* ==========================================================================
   CTA Banner Section
   ========================================================================== */
.cta-banner-section {
  padding: 90px 0;
}

.cta-banner-box {
  background: var(--neo-yellow);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-lg);
  padding: 64px 40px;
  text-align: center;
  color: #0d0d0d;
  box-shadow: 10px 10px 0px var(--shadow-neo);
  position: relative;
}

.cta-banner-box h2 {
  font-size: 2.8rem;
  font-weight: 900;
  margin-bottom: 18px;
  letter-spacing: -0.8px;
}

.cta-banner-box p {
  font-size: 1.2rem;
  max-width: 680px;
  margin: 0 auto 36px;
  font-weight: 600;
}

/* ==========================================================================
   Footer
   Strict requirement:
   页脚只保留这四个标题，内容打开新的页面展示（target="_blank"）：
   1. 网站地图
   2. 关于我们
   3. 服务条款
   4. 隐私政策
   ========================================================================== */
.site-footer {
  background-color: var(--bg-secondary);
  border-top: var(--border-width) solid var(--border-neo);
  padding: 50px 0 40px;
  margin-top: auto;
  transition: var(--transition-theme);
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 36px;
  flex-wrap: wrap;
  margin-bottom: 30px;
}

.footer-link {
  font-size: 1.08rem;
  font-weight: 900;
  color: var(--text-primary);
  background: var(--bg-card);
  border: 2px solid var(--border-neo);
  box-shadow: 3px 3px 0px var(--shadow-neo);
  padding: 8px 18px;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.footer-link:hover {
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0px var(--shadow-neo);
  background: var(--neo-yellow);
  color: #0d0d0d;
}

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 2px dashed var(--border-neo);
  color: var(--text-muted);
  font-size: 0.92rem;
  font-weight: 600;
}

.footer-bottom a {
  color: var(--text-primary);
  text-decoration: underline;
  text-underline-offset: 4px;
}

/* ==========================================================================
   Policy & Articles Prose Pages (About, Terms, Privacy, Sitemap, News)
   ========================================================================== */
.page-header {
  padding: 60px 0 40px;
  background: var(--bg-secondary);
  border-bottom: var(--border-width) solid var(--border-neo);
  text-align: center;
}

.page-header h1 {
  font-size: 2.8rem;
  font-weight: 900;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.page-header p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  font-weight: 600;
}

.page-content {
  padding: 60px 0 80px;
}

.prose {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-lg);
  padding: 50px;
  box-shadow: 8px 8px 0px var(--shadow-neo);
}

.prose h2 {
  font-size: 1.7rem;
  font-weight: 900;
  margin-top: 40px;
  margin-bottom: 18px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--border-neo);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 12px;
}

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

.prose h3 {
  font-size: 1.3rem;
  font-weight: 800;
  margin-top: 26px;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.prose p {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 20px;
}

.prose ul, .prose ol {
  margin-bottom: 22px;
  padding-left: 24px;
}

.prose li {
  font-size: 1.02rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 10px;
}

.prose .callout {
  background: var(--neo-yellow-light);
  border: 2px solid var(--border-neo);
  box-shadow: 4px 4px 0px var(--shadow-neo);
  padding: 20px 24px;
  border-radius: var(--radius-md);
  margin: 28px 0;
  color: #0d0d0d;
  font-weight: 600;
}

/* Article / News Card in Recommend Page */
.article-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 30px;
  margin-top: 20px;
}

.article-card {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-lg);
  padding: 30px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
}

.article-badge {
  display: inline-block;
  background: var(--neo-yellow);
  color: #0d0d0d;
  border: 1.5px solid var(--border-neo);
  font-size: 0.8rem;
  font-weight: 900;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  margin-bottom: 14px;
  align-self: flex-start;
}

.article-title {
  font-size: 1.35rem;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-snippet {
  font-size: 0.98rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 700;
  border-top: 1.5px dashed var(--border-neo);
  padding-top: 14px;
}

/* ==========================================================================
   SEO Article In-Depth Components (Breadcrumb, TOC, Tables, Related)
   ========================================================================== */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-muted);
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.breadcrumb a {
  color: var(--text-primary);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.breadcrumb a:hover {
  color: #ff9900;
}

.breadcrumb-separator {
  color: var(--text-muted);
}

.article-header-box {
  margin-bottom: 36px;
  padding-bottom: 24px;
  border-bottom: 2px solid var(--border-neo);
}

.article-header-box h1 {
  font-size: 2.4rem;
  font-weight: 900;
  line-height: 1.25;
  color: var(--text-primary);
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.article-meta-bar {
  display: flex;
  align-items: center;
  gap: 18px;
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text-muted);
  flex-wrap: wrap;
}

.article-meta-bar span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* Table of Contents (TOC) */
.toc-container {
  background: var(--bg-secondary);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-md);
  box-shadow: 4px 4px 0px var(--shadow-neo);
  padding: 26px 30px;
  margin: 32px 0 44px;
}

.toc-title {
  font-size: 1.18rem;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.toc-list {
  padding-left: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toc-list li {
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--text-secondary);
  list-style: decimal;
}

.toc-list a {
  color: var(--text-primary);
  text-decoration: none;
}

.toc-list a:hover {
  color: #ff9900;
  text-decoration: underline;
}

/* Article Data Table */
.article-table-wrap {
  overflow-x: auto;
  margin: 28px 0;
}

.article-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  box-shadow: 4px 4px 0px var(--shadow-neo);
  font-size: 0.95rem;
}

.article-table th {
  background: var(--neo-yellow);
  color: #0d0d0d;
  font-weight: 900;
  padding: 14px 18px;
  border: 1.5px solid var(--border-neo);
  text-align: left;
}

.article-table td {
  padding: 14px 18px;
  border: 1.5px solid var(--border-neo);
  color: var(--text-secondary);
  font-weight: 600;
}

.article-table tr:nth-child(even) td {
  background: var(--bg-secondary);
}

/* In-Article Callout CTA */
.article-cta-box {
  background: var(--neo-yellow);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-md);
  box-shadow: 6px 6px 0px var(--shadow-neo);
  padding: 32px;
  text-align: center;
  margin: 44px 0;
  color: #0d0d0d;
}

.article-cta-box h3 {
  font-size: 1.6rem;
  font-weight: 900;
  margin-bottom: 12px;
}

.article-cta-box p {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 22px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* Related Reading Section */
.related-section {
  margin-top: 60px;
  padding-top: 40px;
  border-top: 2px solid var(--border-neo);
}

.related-section h3 {
  font-size: 1.5rem;
  font-weight: 900;
  margin-bottom: 24px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 10px;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.related-card {
  background: var(--bg-secondary);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-md);
  box-shadow: 3px 3px 0px var(--shadow-neo);
  padding: 20px;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition-fast);
}

.related-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0px var(--shadow-neo);
}

.related-card h4 {
  font-size: 1.05rem;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 8px;
  line-height: 1.4;
}

.related-card p {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 12px;
  flex-grow: 1;
}

.related-card span {
  font-size: 0.82rem;
  font-weight: 800;
  color: #ff9900;
}

/* Sitemap Grid */
.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
  margin-top: 20px;
}

.sitemap-box {
  background: var(--bg-card);
  border: var(--border-width) solid var(--border-neo);
  border-radius: var(--radius-md);
  padding: 26px;
  box-shadow: 4px 4px 0px var(--shadow-neo);
}

.sitemap-box h3 {
  font-size: 1.25rem;
  font-weight: 900;
  margin-bottom: 18px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 10px;
}

.sitemap-list li {
  margin-bottom: 12px;
  list-style: none;
}

.sitemap-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--text-primary);
  font-size: 0.98rem;
  font-weight: 700;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  border: 1.5px solid var(--border-neo);
  transition: all var(--transition-fast);
}

.sitemap-list a:hover {
  background: var(--neo-yellow);
  color: #0d0d0d;
  transform: translateX(4px);
}

/* ==========================================================================
   Responsive Adaptations (@media)
   ========================================================================== */
@media (max-width: 992px) {
  .hero-title {
    font-size: 3rem;
  }

  .features-grid,
  .pricing-grid,
  .testimonials-grid,
  .article-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .rotary-benchmark-box {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .ai-banner {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .section {
    padding: 60px 0;
  }

  .hero-box {
    padding: 40px 20px;
  }

  .hero-title {
    font-size: 2.2rem;
    letter-spacing: -0.5px;
  }

  .hero-subtitle {
    font-size: 1.1rem;
    margin-bottom: 28px;
  }

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

  /* Single Column Stacking for Pure Touch Convenience */
  .features-grid,
  .pricing-grid,
  .testimonials-grid,
  .sitemap-grid,
  .article-grid,
  .ai-cards-matrix {
    grid-template-columns: 1fr;
  }

  .pricing-card.featured {
    transform: none;
  }

  .btn {
    min-height: 50px;
    font-size: 1.05rem;
    padding: 12px 24px;
  }

  .hero-cta-group {
    flex-direction: column;
    width: 100%;
  }

  .hero-cta-group .btn {
    width: 100%;
  }

  .mobile-toggle {
    display: inline-flex;
  }

  .nav-menu {
    position: fixed;
    top: 76px;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    border-bottom: var(--border-width) solid var(--border-neo);
    flex-direction: column;
    padding: 24px 20px;
    gap: 16px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
    transform: translateY(-130%);
    opacity: 0;
    pointer-events: none;
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  }

  .nav-menu.active {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .footer-nav {
    flex-direction: column;
    gap: 14px;
  }

  .footer-link {
    width: 100%;
    text-align: center;
  }

  .cta-banner-box {
    padding: 44px 20px;
  }

  .cta-banner-box h2 {
    font-size: 2.1rem;
  }

  .prose {
    padding: 30px 20px;
  }

  .rotary-benchmark-box {
    padding: 26px 16px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.95rem;
  }

  .hero-stats-grid {
    grid-template-columns: 1fr;
  }

  .section-title {
    font-size: 1.9rem;
  }
}