/* ==========================================================================
   一元机场 (yiyuanjc.cyou) - 纯原生极简高交互暗黑设计样式表
   Palette: #0d0d0d (Charcoal), #f5d547 (Electric Yellow), #f0ebe1 (Bone White)
   Typography: Space Grotesk (300 Body vs 800 Display)
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@300;400;600;700;800&display=swap');

:root {
  --bg-primary: #0d0d0d;
  --bg-surface: #141414;
  --bg-card: #181818;
  --bg-card-hover: #222222;
  --border-subtle: rgba(240, 235, 225, 0.1);
  --border-active: rgba(245, 213, 71, 0.4);
  --text-primary: #f0ebe1;
  --text-muted: #9e9a91;
  --text-dim: #68655e;
  --accent-yellow: #f5d547;
  --accent-yellow-glow: rgba(245, 213, 71, 0.25);
  --accent-warm: #d4a72c;
  --font-main: 'Space Grotesk', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 9999px;
  --transition-fast: 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-main);
  font-weight: 300;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  background-color: var(--bg-primary);
}

/* 粒子颗粒噪点纹理 Grain Texture Overlay */
.grain-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 999;
  opacity: 0.035;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
}

/* 页面通用容器 */
.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 标题对比度系统 (300 Body vs 800 Display) */
h1, h2, h3, .display-font {
  font-family: var(--font-main);
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text-primary);
  line-height: 1.15;
}

h1 {
  font-size: clamp(2.5rem, 5vw + 1rem, 4.25rem);
}

h2 {
  font-size: clamp(2rem, 3.5vw + 0.5rem, 3rem);
  text-align: center;
  margin-bottom: 1rem;
}

h3 {
  font-size: 1.4rem;
  font-weight: 700;
}

p {
  font-weight: 300;
  color: var(--text-muted);
}

.text-yellow {
  color: var(--accent-yellow);
}

/* 标签胶囊 */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(245, 213, 71, 0.1);
  border: 1px solid rgba(245, 213, 71, 0.3);
  color: var(--accent-yellow);
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
}

.badge-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--accent-yellow);
  box-shadow: 0 0 10px var(--accent-yellow);
  animation: pulse 2s infinite ease-in-out;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.85); }
}

/* 头部导航栏 Header & Nav */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(13, 13, 13, 0.82);
  border-bottom: 1px solid var(--border-subtle);
  transition: var(--transition-fast);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
}

.logo-wrapper {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.logo-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--accent-yellow), #8f7215);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #0d0d0d;
  font-weight: 800;
  font-size: 1.25rem;
  box-shadow: 0 0 20px rgba(245, 213, 71, 0.3);
}

.logo-text {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.logo-sub {
  font-size: 0.75rem;
  color: var(--accent-yellow);
  display: block;
  font-weight: 400;
  letter-spacing: 0.1em;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 400;
  transition: var(--transition-fast);
  position: relative;
  padding: 6px 0;
}

.nav-link:hover, .nav-link.active {
  color: var(--accent-yellow);
}

.nav-link.news-tag {
  color: var(--accent-yellow);
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link.news-tag::after {
  content: '2026';
  font-size: 0.65rem;
  padding: 2px 6px;
  border-radius: 4px;
  background: var(--accent-yellow);
  color: #0d0d0d;
  font-weight: 800;
}

.nav-cta-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--accent-yellow);
  color: #0d0d0d;
  font-weight: 700;
  padding: 10px 22px;
  border-radius: var(--radius-full);
  text-decoration: none;
  font-size: 0.95rem;
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.25s ease;
  box-shadow: 0 4px 18px var(--accent-yellow-glow);
}

.nav-cta-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(245, 213, 71, 0.45);
}

/* 移动端菜单切换按钮 */
.mobile-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--text-primary);
}

.mobile-toggle svg {
  width: 28px;
  height: 28px;
  stroke: var(--text-primary);
}

/* 按钮通用与磁性交互 Magnetic Elements */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 16px 36px;
  border-radius: var(--radius-full);
  font-size: 1.05rem;
  font-weight: 700;
  text-decoration: none;
  transition: transform 0.2s cubic-bezier(0.2, 0.8, 0.2, 1), box-shadow 0.2s ease, background 0.2s ease, border-color 0.2s ease;
  cursor: pointer;
  position: relative;
  will-change: transform;
}

.btn-primary {
  background-color: var(--accent-yellow);
  color: #0d0d0d;
  box-shadow: 0 8px 30px rgba(245, 213, 71, 0.3);
}

.btn-primary:hover {
  background-color: #ffe066;
  box-shadow: 0 12px 40px rgba(245, 213, 71, 0.5);
}

.btn-secondary {
  background: rgba(240, 235, 225, 0.05);
  color: var(--text-primary);
  border: 1px solid var(--border-subtle);
  backdrop-filter: blur(8px);
}

.btn-secondary:hover {
  border-color: var(--accent-yellow);
  color: var(--accent-yellow);
  background: rgba(245, 213, 71, 0.08);
}

/* 主视觉区 Hero Section */
.hero-section {
  position: relative;
  padding: 90px 0 110px 0;
  overflow: hidden;
}

.hero-glow-blob {
  position: absolute;
  top: 15%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 650px;
  height: 650px;
  background: radial-gradient(circle, rgba(245, 213, 71, 0.12) 0%, rgba(212, 167, 44, 0.04) 45%, rgba(13, 13, 13, 0) 70%);
  filter: blur(80px);
  pointer-events: none;
  z-index: 0;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  align-items: center;
  gap: 50px;
  position: relative;
  z-index: 1;
}

.hero-content {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.hero-title {
  margin-bottom: 24px;
}

.hero-subtitle {
  font-size: 1.25rem;
  line-height: 1.7;
  color: var(--text-muted);
  margin-bottom: 36px;
  max-width: 580px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 18px;
  margin-bottom: 40px;
}

.hero-stats {
  display: flex;
  gap: 36px;
  border-top: 1px solid var(--border-subtle);
  padding-top: 28px;
  width: 100%;
}

.stat-item {
  display: flex;
  flex-direction: column;
}

.stat-number {
  font-size: 1.85rem;
  font-weight: 800;
  color: var(--text-primary);
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-dim);
}

/* 3D 悬浮视角卡片 3D Tilt Card */
.hero-tilt-wrapper {
  perspective: 1200px;
  display: flex;
  justify-content: center;
}

.hero-tilt-card {
  width: 100%;
  max-width: 440px;
  background: linear-gradient(145deg, #181818, #111111);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.8), 0 0 40px rgba(245, 213, 71, 0.08);
  transform-style: preserve-3d;
  transition: transform 0.15s ease-out, border-color 0.3s ease;
  position: relative;
  overflow: hidden;
}

.hero-tilt-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent-yellow), transparent);
}

.card-badge-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}

.card-status {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: #6ce07f;
  background: rgba(108, 224, 127, 0.1);
  padding: 4px 12px;
  border-radius: var(--radius-full);
}

.status-dot-green {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #6ce07f;
  box-shadow: 0 0 8px #6ce07f;
}

.card-meter {
  display: flex;
  flex-direction: column;
  gap: 18px;
  margin-bottom: 28px;
}

.meter-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.95rem;
}

.meter-bar {
  width: 100%;
  height: 6px;
  background: rgba(240, 235, 225, 0.08);
  border-radius: var(--radius-full);
  margin-top: 8px;
  overflow: hidden;
}

.meter-fill {
  height: 100%;
  border-radius: var(--radius-full);
  background: linear-gradient(90deg, var(--accent-yellow), #ffe066);
}

.card-footer-box {
  background: rgba(0, 0, 0, 0.4);
  border-radius: var(--radius-md);
  padding: 16px;
  display: flex;
  justify-content: space-around;
  border: 1px solid var(--border-subtle);
}

.box-mini {
  text-align: center;
}

.box-mini-num {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--accent-yellow);
}

.box-mini-text {
  font-size: 0.75rem;
  color: var(--text-dim);
}

/* 产品核心优势介绍 3个图文卡片 */
.features-section {
  padding: 100px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 60px auto;
}

.section-desc {
  font-size: 1.1rem;
  color: var(--text-muted);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

/* 3D 倾斜卡片 (JS-driven cursor tilt) */
.tilt-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 40px 32px;
  position: relative;
  transition: transform 0.15s ease-out, border-color 0.3s ease, box-shadow 0.3s ease;
  transform-style: preserve-3d;
  will-change: transform;
  overflow: hidden;
}

.tilt-card:hover {
  border-color: var(--border-active);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.6), 0 0 25px rgba(245, 213, 71, 0.08);
}

.feature-icon-box {
  width: 64px;
  height: 64px;
  border-radius: 16px;
  background: rgba(245, 213, 71, 0.08);
  border: 1px solid rgba(245, 213, 71, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  color: var(--accent-yellow);
  font-size: 1.8rem;
  transform: translateZ(30px);
}

.tilt-card h3 {
  margin-bottom: 14px;
  transform: translateZ(25px);
}

.tilt-card p {
  line-height: 1.7;
  font-size: 0.98rem;
  transform: translateZ(20px);
}

.feature-tag-list {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 20px;
  transform: translateZ(15px);
}

.feature-tag-list span {
  font-size: 0.75rem;
  background: rgba(240, 235, 225, 0.05);
  border: 1px solid var(--border-subtle);
  padding: 3px 10px;
  border-radius: var(--radius-full);
  color: var(--text-muted);
}

/* 流媒体与 AI 支持图卡 */
.streaming-section {
  padding: 100px 0;
  background: linear-gradient(180deg, var(--bg-primary) 0%, #111111 50%, var(--bg-primary) 100%);
}

.streaming-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 48px;
}

.stream-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  transition: var(--transition-fast);
}

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

.stream-icon {
  font-size: 2.2rem;
  margin-bottom: 16px;
}

.stream-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.stream-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* 节点网络区域 Node Network Section */
.nodes-section {
  padding: 100px 0;
  position: relative;
}

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

.node-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  flex-direction: column;
  position: relative;
  transform-style: preserve-3d;
  transition: transform 0.15s ease-out, border-color 0.3s ease;
}

.node-card:hover {
  border-color: var(--accent-yellow);
}

.node-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.node-flag-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.15rem;
  font-weight: 700;
}

.node-flag {
  font-size: 1.4rem;
}

.node-ping {
  font-size: 0.85rem;
  font-weight: 700;
  color: #6ce07f;
  background: rgba(108, 224, 127, 0.08);
  padding: 3px 8px;
  border-radius: var(--radius-full);
}

.node-specs {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.85rem;
  color: var(--text-dim);
}

/* 粘性视差区块 Sticky Parallax Section with Fixed Gradient Blob */
.parallax-section {
  position: relative;
  min-height: 120vh;
  padding: 120px 0;
  overflow: hidden;
}

.parallax-sticky-bg {
  position: sticky;
  top: 15%;
  left: 0;
  width: 100%;
  display: flex;
  justify-content: center;
  pointer-events: none;
  z-index: 1;
}

.fixed-gradient-blob {
  width: 550px;
  height: 550px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(245, 213, 71, 0.18) 0%, rgba(212, 167, 44, 0.06) 50%, rgba(13, 13, 13, 0) 75%);
  filter: blur(70px);
  animation: blobFloat 12s infinite alternate ease-in-out;
}

@keyframes blobFloat {
  0% { transform: scale(1) translate(0, 0); }
  50% { transform: scale(1.15) translate(20px, -20px); }
  100% { transform: scale(0.95) translate(-20px, 20px); }
}

.parallax-content {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  gap: 120px;
  max-width: 820px;
  margin: 0 auto;
}

.parallax-card {
  background: rgba(20, 20, 20, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 48px;
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.7);
  transition: border-color 0.3s ease;
}

.parallax-card:hover {
  border-color: var(--border-active);
}

.parallax-card h3 {
  font-size: 1.85rem;
  margin-bottom: 16px;
  color: var(--accent-yellow);
}

.parallax-card p {
  font-size: 1.1rem;
  line-height: 1.8;
}

/* 套餐价格对比表 Pricing Section (Flip Card Interaction) */
.pricing-section {
  padding: 100px 0;
  position: relative;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 48px;
  perspective: 1200px;
}

/* 翻转卡片容器 Flip Card */
.flip-card {
  background-color: transparent;
  height: 480px;
  perspective: 1000px;
}

.flip-card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  text-align: left;
  transition: transform 0.7s cubic-bezier(0.4, 0.2, 0.2, 1);
  transform-style: preserve-3d;
  border-radius: var(--radius-lg);
}

.flip-card:hover .flip-card-inner,
.flip-card.is-flipped .flip-card-inner {
  transform: rotateY(180deg);
}

.flip-card-front, .flip-card-back {
  position: absolute;
  width: 100%;
  height: 100%;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface);
}

.flip-card-front.featured {
  border-color: var(--accent-yellow);
  background: linear-gradient(180deg, #1c1c18 0%, #141414 100%);
  box-shadow: 0 0 35px rgba(245, 213, 71, 0.12);
}

.flip-card-back {
  transform: rotateY(180deg);
  background: linear-gradient(145deg, #181818, #0e0e0e);
  border-color: var(--accent-yellow);
}

.pricing-badge-popular {
  position: absolute;
  top: -12px;
  right: 24px;
  background: var(--accent-yellow);
  color: #0d0d0d;
  font-size: 0.75rem;
  font-weight: 800;
  padding: 4px 12px;
  border-radius: var(--radius-full);
}

.pricing-title {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.pricing-price {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin: 16px 0 24px 0;
}

.price-currency {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--accent-yellow);
}

.price-val {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1;
  color: var(--text-primary);
}

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

.pricing-features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 24px;
}

.pricing-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.92rem;
  color: var(--text-muted);
}

.pricing-features li svg {
  width: 16px;
  height: 16px;
  stroke: var(--accent-yellow);
  flex-shrink: 0;
}

.flip-hint {
  font-size: 0.78rem;
  color: var(--accent-yellow);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  margin-top: 10px;
  opacity: 0.85;
}

.flip-back-content {
  display: flex;
  flex-direction: column;
  height: 100%;
  justify-content: space-between;
}

.flip-back-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent-yellow);
  margin-bottom: 14px;
}

.flip-back-details {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.flip-back-details li {
  line-height: 1.5;
  border-bottom: 1px dashed rgba(240, 235, 225, 0.08);
  padding-bottom: 8px;
}

.btn-card {
  width: 100%;
  padding: 12px 20px;
  font-size: 0.95rem;
}

/* 用户评价 User Reviews */
.reviews-section {
  padding: 100px 0;
  background: var(--bg-surface);
}

.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin-top: 48px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 32px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition-fast);
}

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

.review-stars {
  color: var(--accent-yellow);
  font-size: 1.1rem;
  letter-spacing: 2px;
  margin-bottom: 16px;
}

.review-text {
  font-size: 0.98rem;
  line-height: 1.7;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.review-user {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid var(--border-subtle);
  padding-top: 16px;
}

.user-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: rgba(245, 213, 71, 0.15);
  color: var(--accent-yellow);
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
}

.user-meta-name {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
}

.user-meta-role {
  font-size: 0.8rem;
  color: var(--text-dim);
}

/* 常见问题 FAQ Section */
.faq-section {
  padding: 100px 0;
}

.faq-list {
  max-width: 840px;
  margin: 48px auto 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.25s ease;
}

.faq-item:hover, .faq-item.active {
  border-color: var(--border-active);
}

.faq-question {
  width: 100%;
  background: none;
  border: none;
  padding: 24px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  text-align: left;
  cursor: pointer;
  color: var(--text-primary);
  font-family: var(--font-main);
  font-size: 1.1rem;
  font-weight: 700;
}

.faq-icon {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: var(--accent-yellow);
  transition: transform 0.3s ease;
  flex-shrink: 0;
}

.faq-item.active .faq-icon {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s cubic-bezier(0, 1, 0, 1);
  padding: 0 28px;
}

.faq-item.active .faq-answer {
  max-height: 400px;
  padding: 0 28px 24px 28px;
  transition: max-height 0.35s cubic-bezier(1, 0, 1, 0);
}

.faq-answer p {
  color: var(--text-muted);
  line-height: 1.7;
  font-size: 0.98rem;
}

/* 页脚 Footer - 严格规范：只保留4个标题，打开新页面 */
.site-footer {
  border-top: 1px solid var(--border-subtle);
  background: #090909;
  padding: 60px 0 36px 0;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 36px;
}

.footer-nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 40px;
  list-style: none;
  flex-wrap: wrap;
}

.footer-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 1.05rem;
  font-weight: 600;
  transition: var(--transition-fast);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
}

.footer-link:hover {
  color: var(--accent-yellow);
  background: rgba(245, 213, 71, 0.08);
}

.footer-divider {
  width: 100%;
  max-width: 900px;
  height: 1px;
  background: var(--border-subtle);
}

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

/* 资讯与文章页面专属样式 (Articles & News Pages) */
.article-hub-header {
  padding: 80px 0 40px 0;
  text-align: center;
}

.article-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  margin-top: 40px;
}

.article-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 36px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition-fast);
}

.article-card:hover {
  border-color: var(--accent-yellow);
  transform: translateY(-4px);
}

.article-badge {
  align-self: flex-start;
  font-size: 0.75rem;
  padding: 4px 10px;
  border-radius: 4px;
  background: rgba(245, 213, 71, 0.1);
  color: var(--accent-yellow);
  margin-bottom: 16px;
  font-weight: 700;
}

.article-title {
  font-size: 1.45rem;
  font-weight: 700;
  margin-bottom: 14px;
  line-height: 1.35;
}

.article-excerpt {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 24px;
}

.article-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px solid var(--border-subtle);
  padding-top: 16px;
  font-size: 0.85rem;
  color: var(--text-dim);
}

.article-read-btn {
  color: var(--accent-yellow);
  text-decoration: none;
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.article-read-btn:hover {
  text-decoration: underline;
}

.content-page-wrapper {
  max-width: 860px;
  margin: 60px auto 100px auto;
  padding: 48px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
}

.content-page-wrapper h1 {
  font-size: 2.4rem;
  margin-bottom: 24px;
  color: var(--text-primary);
}

.content-page-wrapper h2 {
  text-align: left;
  font-size: 1.6rem;
  margin: 36px 0 16px 0;
  color: var(--accent-yellow);
}

.content-page-wrapper p {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.content-page-wrapper ul {
  margin: 16px 0 24px 24px;
  color: var(--text-muted);
}

.content-page-wrapper li {
  margin-bottom: 10px;
  line-height: 1.7;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--accent-yellow);
  text-decoration: none;
  font-weight: 600;
  margin-bottom: 30px;
}

/* ==========================================================================
   响应式适配 Responsive Queries (@media)
   确保在手机端完美单栏显示，按钮适合手指点击 (>=44px)
   ========================================================================== */

@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }

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

  .hero-subtitle {
    margin-left: auto;
    margin-right: auto;
  }

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

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

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

  .streaming-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .node-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
    position: absolute;
    top: 80px;
    left: 0;
    right: 0;
    background: rgba(13, 13, 13, 0.98);
    flex-direction: column;
    padding: 24px;
    gap: 20px;
    border-bottom: 1px solid var(--border-subtle);
  }

  .nav-menu.is-active {
    display: flex;
  }

  .mobile-toggle {
    display: block;
  }

  .features-grid,
  .pricing-grid,
  .reviews-grid,
  .streaming-grid,
  .node-grid,
  .article-grid {
    grid-template-columns: 1fr; /* 手机端完美单栏显示 */
  }

  .flip-card {
    height: 440px;
  }

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

  .hero-actions .btn {
    width: 100%;
    min-height: 52px; /* 适合手指点击 */
  }

  .footer-nav {
    flex-direction: column;
    gap: 18px;
  }

  .content-page-wrapper {
    padding: 24px 18px;
    margin: 30px 16px 60px 16px;
  }
}