/* ==========================================================================
   赔钱机场 - 极简高能网络加速器落地页 CSS 样式表
   ========================================================================== */

/* 重置与变量定义 */
:root {
  --bg-dark: #0a0d14;
  --bg-card: rgba(18, 24, 38, 0.75);
  --bg-card-hover: rgba(28, 36, 56, 0.85);
  --border-color: rgba(255, 255, 255, 0.1);
  --border-glow: rgba(255, 77, 77, 0.4);
  
  --primary: #ff4d4d; /* 赔钱红 / 警示超值 */
  --primary-hover: #ff6666;
  --primary-glow: rgba(255, 77, 77, 0.3);
  
  --accent: #00f2fe; /* 科技青 */
  --accent-purple: #7928ca;
  --gold: #ffb703;
  
  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --radius-lg: 16px;
  --radius-md: 12px;
  --radius-sm: 8px;
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-family);
  background-color: var(--bg-dark);
  color: var(--text-main);
  overflow-x: hidden;
  line-height: 1.6;
}

body {
  position: relative;
  min-height: 100vh;
  background: radial-gradient(circle at 15% 15%, rgba(121, 40, 202, 0.15) 0%, transparent 45%),
              radial-gradient(circle at 85% 65%, rgba(255, 77, 77, 0.12) 0%, transparent 40%),
              radial-gradient(circle at 50% 90%, rgba(0, 242, 254, 0.1) 0%, transparent 50%),
              #0a0d14;
  background-attachment: fixed;
}

/* 渐变背景线条网格 */
body::before {
  content: "";
  position: fixed;
  top: 0; left: 0; width: 100%; height: 100%;
  background-image: linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
  z-index: 0;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  position: relative;
  z-index: 1;
}

/* 导航栏 */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(10, 13, 20, 0.8);
  border-bottom: 1px solid var(--border-color);
  padding: 16px 0;
}

.header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.4rem;
  font-weight: 800;
  color: #fff;
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  user-select: none;
}

.logo:hover {
  transform: scale(1.03);
}

.logo-icon {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, var(--primary), var(--accent-purple));
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 15px var(--primary-glow);
  font-size: 1.3rem;
  animation: logoPulse 3s infinite ease-in-out;
}

@keyframes logoPulse {
  0%, 100% { box-shadow: 0 0 15px rgba(255, 77, 77, 0.4); }
  50% { box-shadow: 0 0 25px rgba(0, 242, 254, 0.6); }
}

.logo-text span {
  color: var(--primary);
}

.nav-links {
  display: flex;
  gap: 24px;
  align-items: center;
}

.nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  transition: var(--transition);
}

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

/* 按钮规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 1rem;
  font-weight: 700;
  border-radius: var(--radius-md);
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  outline: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary) 0%, #e63946 100%);
  color: #fff;
  box-shadow: 0 4px 20px var(--primary-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(255, 77, 77, 0.5);
  background: linear-gradient(135deg, #ff6666 0%, #ff4d4d 100%);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  border: 1px solid var(--border-color);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: rgba(255, 255, 255, 0.3);
  transform: translateY(-2px);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.15rem;
  border-radius: 30px;
}

/* 通用章节样式 */
.section {
  padding: 100px 0 60px;
  position: relative;
}

.section-title-wrap {
  text-align: center;
  margin-bottom: 50px;
}

.badge {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(255, 77, 77, 0.15);
  border: 1px solid rgba(255, 77, 77, 0.3);
  border-radius: 20px;
  color: var(--primary);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 14px;
  letter-spacing: 1px;
}

.section-title {
  font-size: 2.3rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 12px;
}

.section-subtitle {
  color: var(--text-muted);
  font-size: 1.05rem;
  max-width: 680px;
  margin: 0 auto;
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 120px;
  text-align: center;
}

.hero-content {
  max-width: 860px;
  margin: 0 auto;
}

.hero-headline {
  font-size: 3.5rem;
  font-weight: 900;
  line-height: 1.15;
  margin-bottom: 24px;
  letter-spacing: -0.5px;
}

.gradient-text {
  background: linear-gradient(135deg, #ffffff 0%, var(--primary) 50%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-sub {
  font-size: 1.25rem;
  color: var(--text-muted);
  margin-bottom: 40px;
  line-height: 1.7;
}

.hero-sub strong {
  color: var(--gold);
}

.hero-cta-group {
  display: flex;
  gap: 20px;
  justify-content: center;
  align-items: center;
  margin-bottom: 50px;
  flex-wrap: wrap;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 30px;
  background: var(--bg-card);
  padding: 24px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  backdrop-filter: blur(12px);
}

.stat-item {
  text-align: center;
}

.stat-num {
  font-size: 2rem;
  font-weight: 800;
  color: var(--accent);
}

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

/* 核心优势卡片 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: var(--transition);
  backdrop-filter: blur(12px);
  position: relative;
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  display: block;
  cursor: pointer;
}

.card:hover {
  transform: translateY(-8px);
  border-color: var(--border-glow);
  background: var(--bg-card-hover);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
}

.card-icon {
  width: 60px;
  height: 60px;
  border-radius: var(--radius-md);
  background: rgba(255, 77, 77, 0.12);
  color: var(--primary);
  font-size: 1.8rem;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
}

.card-title {
  font-size: 1.35rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 14px;
}

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

/* 流媒体与 AI 支持 */
.media-ai-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.media-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  align-items: center;
  gap: 16px;
  transition: var(--transition);
  text-decoration: none;
  color: inherit;
  cursor: pointer;
}

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

.media-icon {
  font-size: 2.2rem;
  width: 50px;
  text-align: center;
}

.media-info h4 {
  color: #fff;
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.media-info p {
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* 价格对比表 (赔钱元素) */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: var(--transition);
}

.pricing-card.popular {
  border-color: var(--primary);
  background: rgba(255, 77, 77, 0.08);
  box-shadow: 0 0 30px rgba(255, 77, 77, 0.25);
  transform: scale(1.04);
}

.pricing-card.popular::before {
  content: "老板亏出血 推荐";
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: #fff;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: 20px;
}

.pricing-header h3 {
  font-size: 1.3rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 8px;
}

.pricing-tag {
  font-size: 0.8rem;
  color: var(--primary);
  background: rgba(255, 77, 77, 0.15);
  padding: 3px 8px;
  border-radius: 4px;
  display: inline-block;
  margin-bottom: 16px;
}

.price-wrap {
  margin-bottom: 24px;
}

.price {
  font-size: 2.5rem;
  font-weight: 900;
  color: #fff;
}

.price span {
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 400;
}

.original-price {
  font-size: 0.85rem;
  color: var(--text-dim);
  text-decoration: line-through;
  margin-left: 6px;
}

.pricing-features {
  list-style: none;
  margin-bottom: 30px;
  flex-grow: 1;
}

.pricing-features li {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.pricing-features li::before {
  content: "✓";
  color: #00e676;
  font-weight: bold;
}

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

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

.faq-question {
  padding: 20px 24px;
  font-size: 1.08rem;
  font-weight: 700;
  color: #fff;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.faq-question::after {
  content: "+";
  font-size: 1.4rem;
  color: var(--primary);
  transition: var(--transition);
}

.faq-item.active .faq-question::after {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
  padding: 0 24px;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

.faq-item.active .faq-answer {
  max-height: 500px;
  padding: 0 24px 20px 24px;
}

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

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.review-stars {
  color: var(--gold);
  font-size: 1rem;
}

.review-text {
  color: var(--text-muted);
  font-size: 0.93rem;
  font-style: italic;
  flex-grow: 1;
}

.review-user {
  display: flex;
  align-items: center;
  gap: 12px;
}

.avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-purple));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  color: #fff;
}

.user-info h5 {
  color: #fff;
  font-size: 0.95rem;
}

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

/* 热门 SEO / GEO 文章预览导航块 */
.articles-preview-section {
  padding: 60px 0;
  background: rgba(0, 0, 0, 0.3);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
  margin-top: 30px;
}

.article-link-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  text-decoration: none;
  color: var(--text-main);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.article-link-card:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
  background: var(--bg-card-hover);
}

.article-tag {
  font-size: 0.75rem;
  color: var(--accent);
  font-weight: 600;
}

.article-title-text {
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.4;
}

/* 页脚 - 只保留指定4个标题 */
.footer {
  background: #06080d;
  border-top: 1px solid var(--border-color);
  padding: 40px 0;
  text-align: center;
}

.footer-nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 40px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.footer-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 1.05rem;
  font-weight: 600;
  transition: var(--transition);
}

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

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

/* 右侧悬浮章节上下导航箭头 */
.section-nav-widget {
  position: fixed;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 12px;
  align-items: center;
}

.nav-arrow-btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: rgba(18, 24, 38, 0.85);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  cursor: pointer;
  transition: var(--transition);
  backdrop-filter: blur(10px);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.4);
}

.nav-arrow-btn:hover {
  background: var(--primary);
  border-color: var(--primary);
  transform: scale(1.15);
  box-shadow: 0 0 20px var(--primary-glow);
}

.nav-arrow-btn:active {
  transform: scale(0.95);
}

.section-indicator {
  font-size: 0.75rem;
  color: var(--text-muted);
  background: rgba(0, 0, 0, 0.6);
  padding: 4px 8px;
  border-radius: 10px;
  font-weight: 700;
  letter-spacing: 1px;
}

/* 移动端媒体查询 (@media) */
@media (max-width: 992px) {
  .features-grid, .pricing-grid, .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-card.popular {
    transform: none;
  }
  .hero-headline {
    font-size: 2.6rem;
  }
}

@media (max-width: 768px) {
  .header-container {
    flex-direction: row;
  }
  .nav-links {
    display: none; /* 移动端精简顶部导航，聚焦于核心 */
  }
  .hero-headline {
    font-size: 2.1rem;
  }
  .hero-sub {
    font-size: 1rem;
  }
  .features-grid, .pricing-grid, .reviews-grid {
    grid-template-columns: 1fr;
  }
  .hero-stats {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .section-nav-widget {
    right: 12px;
  }
  .nav-arrow-btn {
    width: 38px;
    height: 38px;
    font-size: 1rem;
  }
  .footer-nav {
    gap: 20px;
    flex-direction: column;
  }
  .btn-lg {
    width: 100%;
    padding: 14px 20px;
  }
}