/* ==========================================================================
   尔湾云 (Erwan Yun) - 极致纯净原生 CSS 样式表
   无外部框架依赖 / 秒开极速加载 / 全端响应式自适应
   ========================================================================== */

/* --- 1. CSS 全局变量与 Reset --- */
:root {
  --bg-dark: #090d16;
  --bg-card: rgba(22, 30, 49, 0.7);
  --bg-card-hover: rgba(30, 42, 69, 0.85);
  --border-color: rgba(255, 255, 255, 0.1);
  --border-color-glow: rgba(59, 130, 246, 0.5);
  
  --primary-blue: #3b82f6;
  --primary-cyan: #06b6d4;
  --primary-purple: #8b5cf6;
  --accent-pink: #ec4899;
  
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --text-dim: #6b7280;
  
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-pill: 9999px;
  
  --shadow-glow: 0 0 25px rgba(59, 130, 246, 0.35);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-dark);
  color: var(--text-main);
  font-family: var(--font-family);
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  line-height: 1.6;
  overflow-x: hidden;
  background: radial-gradient(circle at 50% 0%, #172554 0%, #090d16 70%);
  background-attachment: fixed;
}

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

/* --- 2. 通用容器与排版 --- */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.section {
  padding: 90px 0;
  position: relative;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  text-align: center;
  margin-bottom: 16px;
  background: linear-gradient(135deg, #ffffff 0%, #93c5fd 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--text-muted);
  text-align: center;
  max-width: 680px;
  margin: 0 auto 50px auto;
}

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

/* --- 3. 按钮样式 (CTA Buttons) --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  transition: var(--transition);
  cursor: pointer;
  min-height: 48px;
  text-align: center;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
  color: #ffffff;
  box-shadow: 0 4px 20px rgba(59, 130, 246, 0.4);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(139, 92, 246, 0.6);
  background: linear-gradient(135deg, #2563eb, #7c3aed);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-main);
  border: 1px solid var(--border-color);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.3);
  transform: translateY(-2px);
}

.btn-block {
  width: 100%;
}

/* --- 4. Header 导航栏 --- */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(16px);
  background: rgba(9, 13, 22, 0.75);
  border-bottom: 1px solid var(--border-color);
  height: 72px;
  display: flex;
  align-items: center;
}

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

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.4rem;
  font-weight: 800;
  letter-spacing: -0.5px;
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary-cyan), var(--primary-purple));
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: bold;
}

.nav-links {
  display: flex;
  gap: 32px;
  list-style: none;
}

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

.nav-links a:hover {
  color: #ffffff;
}

/* --- 5. Hero 区域 --- */
.hero {
  padding: 120px 0 80px 0;
  text-align: center;
  position: relative;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.3);
  border-radius: var(--radius-pill);
  font-size: 0.875rem;
  color: #93c5fd;
  margin-bottom: 24px;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: -1px;
  margin-bottom: 24px;
}

.hero-desc {
  font-size: 1.25rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 40px auto;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 50px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  max-width: 800px;
  margin: 0 auto;
  padding: 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  backdrop-filter: blur(12px);
}

.stat-item h3 {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--primary-cyan);
}

.stat-item p {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* --- 6. 核心优势区 --- */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 32px 24px;
  transition: var(--transition);
  backdrop-filter: blur(10px);
}

.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-color-glow);
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
}

.feature-icon {
  width: 52px;
  height: 52px;
  background: rgba(59, 130, 246, 0.15);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--primary-cyan);
}

.feature-card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.925rem;
}

/* --- 7. 流媒体与 AI 支持 --- */
.unlock-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.unlock-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px;
  backdrop-filter: blur(10px);
}

.unlock-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}

.unlock-tag {
  background: rgba(139, 92, 246, 0.2);
  color: #c4b5fd;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
}

.unlock-tags-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.service-pill {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  font-size: 0.85rem;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 6px;
}

/* --- 8. 套餐价格对比表 --- */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: var(--transition);
  backdrop-filter: blur(10px);
}

.pricing-card.featured {
  background: linear-gradient(180deg, rgba(30, 42, 69, 0.95) 0%, rgba(15, 23, 42, 0.95) 100%);
  border: 2px solid var(--primary-blue);
  box-shadow: 0 0 35px rgba(59, 130, 246, 0.25);
  transform: scale(1.03);
}

.pricing-ribbon {
  position: absolute;
  top: -12px;
  right: 20px;
  background: linear-gradient(135deg, var(--primary-cyan), var(--primary-blue));
  color: white;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  text-transform: uppercase;
}

.pricing-header h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.pricing-header p {
  color: var(--text-muted);
  font-size: 0.875rem;
  margin-bottom: 20px;
}

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

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

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

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

.pricing-features li {
  margin-bottom: 12px;
  font-size: 0.9rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 10px;
}

.pricing-features li svg {
  color: var(--primary-cyan);
  flex-shrink: 0;
}

/* --- 9. 用户评价 --- */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.review-text {
  font-size: 0.95rem;
  color: var(--text-muted);
  font-style: italic;
  margin-bottom: 20px;
  line-height: 1.6;
}

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

.avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-blue), var(--accent-pink));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  color: white;
}

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

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

/* --- 10. FAQ 常见问题 --- */
.faq-grid {
  max-width: 800px;
  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);
  padding: 24px;
}

.faq-item h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: #ffffff;
}

.faq-item p {
  font-size: 0.925rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* --- 11. 页脚 (Footer - 规范要求仅保留 4 个新页面入口) --- */
.footer {
  border-top: 1px solid var(--border-color);
  background: rgba(5, 8, 14, 0.9);
  padding: 50px 0;
  text-align: center;
}

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

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

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

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

/* --- 12. 附属页面专用通用样式 (About, Terms, Privacy, Sitemap) --- */
.page-header {
  padding: 80px 0 40px 0;
  text-align: center;
  border-bottom: 1px solid var(--border-color);
  background: rgba(15, 23, 42, 0.4);
}

.page-header h1 {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.page-content {
  padding: 60px 0;
  max-width: 860px;
}

.content-block {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px;
  margin-bottom: 30px;
}

.content-block h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--primary-cyan);
}

.content-block p {
  color: var(--text-muted);
  margin-bottom: 16px;
  line-height: 1.8;
}

.content-block ul {
  margin-left: 20px;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.content-block li {
  margin-bottom: 8px;
}

/* --- 13. 响应式适配 (@media Queries) --- */
@media (max-width: 768px) {
  .nav-links {
    display: none; /* 移动端精简导航 */
  }

  .hero {
    padding: 70px 0 50px 0;
  }

  .hero-title {
    font-size: 2.2rem;
  }

  .hero-desc {
    font-size: 1rem;
  }

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

  .hero-actions .btn {
    width: 100%;
  }

  .hero-stats {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .section {
    padding: 60px 0;
  }

  .section-title {
    font-size: 1.75rem;
  }

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

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

  .content-block {
    padding: 24px;
  }
}