/* ==========================================================================
   尔湾云 (Irvine Cloud) - 极简超高速全局 CSS 样式表
   无任何第三方依赖 | 响应式适配 | 秒开加载优化
   ========================================================================== */

:root {
  --bg-primary: #0a0d14;
  --bg-secondary: #121723;
  --bg-card: #182030;
  --bg-card-hover: #1e283d;
  --border-color: rgba(255, 255, 255, 0.08);
  --border-highlight: rgba(0, 242, 254, 0.3);
  
  --text-main: #f0f4f8;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  
  --accent-cyan: #00f2fe;
  --accent-blue: #4facfe;
  --accent-purple: #7f00ff;
  --accent-gradient: linear-gradient(135deg, #00f2fe 0%, #4facfe 50%, #7f00ff 100%);
  --accent-gradient-hover: linear-gradient(135deg, #38f9d7 0%, #4facfe 50%, #6b00d7 100%);
  --gold-badge: linear-gradient(135deg, #ffe066 0%, #f59f00 100%);
  
  --shadow-glow: 0 0 25px rgba(0, 242, 254, 0.15);
  --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  
  --max-width: 1200px;
  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
}

/* 基础重置 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-stack);
  background-color: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
  transition: all 0.25s ease;
}

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

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* 通用按钮组件 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.75rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-align: center;
  border: none;
  min-height: 48px; /* 移动端最佳触控高度 */
  white-space: nowrap;
}

.btn-primary {
  background: var(--accent-gradient);
  color: #000;
  font-weight: 700;
  box-shadow: 0 4px 20px rgba(0, 242, 254, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0, 242, 254, 0.5);
  background: var(--accent-gradient-hover);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}

.btn-block {
  width: 100%;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0.85rem;
  font-size: 0.825rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  background: rgba(0, 242, 254, 0.1);
  color: var(--accent-cyan);
  border: 1px solid rgba(0, 242, 254, 0.2);
}

/* 模块通用标题 */
.section-header {
  text-align: center;
  max-width: 750px;
  margin: 0 auto 3.5rem auto;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
  background: linear-gradient(180deg, #ffffff 0%, #cbd5e1 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

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

/* ==========================================================================
   1. 头部导航 (Header & Navbar)
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(10, 13, 20, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 0;
}

.nav-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.01em;
}

.logo-icon {
  width: 34px;
  height: 34px;
  background: var(--accent-gradient);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #000;
  font-weight: 900;
  font-size: 1.2rem;
}

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

.nav-menu {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

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

.nav-link:hover {
  color: var(--accent-cyan);
}

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

/* ==========================================================================
   2. 主视觉区 (Hero Section)
   ========================================================================== */
.hero {
  padding: 5rem 0 4rem 0;
  position: relative;
  overflow: hidden;
  text-align: center;
}

.hero::before {
  content: '';
  position: absolute;
  top: -100px;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 400px;
  background: radial-gradient(circle, rgba(0, 242, 254, 0.12) 0%, rgba(127, 0, 255, 0.05) 50%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 900px;
  margin: 0 auto;
}

.hero-badge {
  margin-bottom: 1.5rem;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
}

.hero-title-gradient {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: 1.25rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 2.5rem auto;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.25rem;
  margin-bottom: 3rem;
  flex-wrap: wrap;
}

.hero-features-strip {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
  flex-wrap: wrap;
}

.strip-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.95rem;
  color: var(--text-muted);
}

.strip-item svg {
  color: var(--accent-cyan);
}

/* ==========================================================================
   3. 核心优势 (Core Advantages)
   ========================================================================== */
.features-section {
  padding: 5rem 0;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 2rem;
  transition: all 0.3s ease;
}

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

.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-sm);
  background: rgba(0, 242, 254, 0.08);
  border: 1px solid rgba(0, 242, 254, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  margin-bottom: 1.25rem;
}

.feature-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--text-main);
}

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

/* ==========================================================================
   4. 流媒体与 AI 支持 (Streaming & AI Unlocking)
   ========================================================================== */
.unlock-section {
  padding: 5rem 0;
}

.unlock-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
}

.unlock-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
}

.unlock-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.unlock-icon-badge {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, rgba(79, 172, 254, 0.2), rgba(127, 0, 255, 0.2));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
}

.unlock-box-title {
  font-size: 1.5rem;
  font-weight: 800;
}

.unlock-box-desc {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 2rem;
}

.tags-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.tag-item {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-color);
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-main);
}

.tag-item:hover {
  border-color: var(--accent-cyan);
  background: rgba(0, 242, 254, 0.05);
}

/* ==========================================================================
   5. 套餐价格表 (Pricing Tables)
   ========================================================================== */
.pricing-section {
  padding: 5rem 0;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  align-items: stretch;
}

.price-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem 2rem;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: all 0.3s ease;
}

.price-card.popular {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 35px rgba(0, 242, 254, 0.15);
  background: linear-gradient(180deg, rgba(0, 242, 254, 0.03) 0%, var(--bg-card) 100%);
  transform: scale(1.03);
}

.price-card:hover {
  border-color: var(--accent-cyan);
}

.popular-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--accent-gradient);
  color: #000;
  font-size: 0.8rem;
  font-weight: 800;
  padding: 0.3rem 1.25rem;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.plan-name {
  font-size: 1.35rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
}

.plan-desc {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  min-height: 42px;
}

.plan-price-box {
  display: flex;
  align-items: baseline;
  gap: 0.3rem;
  margin-bottom: 1.75rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.currency {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent-cyan);
}

.amount {
  font-size: 2.75rem;
  font-weight: 900;
  line-height: 1;
  color: var(--text-main);
}

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

.plan-features {
  list-style: none;
  margin-bottom: 2rem;
  flex-grow: 1;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-size: 0.925rem;
  color: var(--text-muted);
  margin-bottom: 0.85rem;
}

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

/* ==========================================================================
   6. 用户评价 (Testimonials)
   ========================================================================== */
.reviews-section {
  padding: 5rem 0;
}

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

.review-stars {
  color: #f59f00;
  display: flex;
  gap: 0.25rem;
  margin-bottom: 1rem;
}

.review-text {
  font-size: 0.95rem;
  color: var(--text-main);
  line-height: 1.6;
  margin-bottom: 1.5rem;
  font-style: italic;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-color);
}

.author-avatar {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-full);
  background: var(--accent-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #000;
  font-weight: 800;
  font-size: 1rem;
}

.author-name {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
}

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

/* ==========================================================================
   7. 常见问题 (FAQ)
   ========================================================================== */
.faq-section {
  padding: 5rem 0;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.faq-grid {
  max-width: 850px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem 1.75rem;
}

.faq-question {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.65rem;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.faq-question::before {
  content: 'Q';
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  background: rgba(0, 242, 254, 0.15);
  color: var(--accent-cyan);
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 800;
  flex-shrink: 0;
}

.faq-answer {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
  padding-left: 2.25rem;
}

/* ==========================================================================
   8. 底部 CTA 横幅 (CTA Banner)
   ========================================================================== */
.cta-banner {
  padding: 5rem 0;
  text-align: center;
}

.cta-box {
  background: linear-gradient(135deg, rgba(0, 242, 254, 0.1) 0%, rgba(127, 0, 255, 0.1) 100%);
  border: 1px solid rgba(0, 242, 254, 0.3);
  border-radius: var(--radius-lg);
  padding: 4rem 2rem;
  max-width: 900px;
  margin: 0 auto;
  position: relative;
  overflow: hidden;
}

.cta-box h2 {
  font-size: 2.5rem;
  font-weight: 900;
  margin-bottom: 1rem;
}

.cta-box p {
  color: var(--text-muted);
  font-size: 1.15rem;
  max-width: 600px;
  margin: 0 auto 2.25rem auto;
}

/* ==========================================================================
   9. 页脚 (Footer) - 严格保留 4 个新标签页标题
   ========================================================================== */
.site-footer {
  background: #07090e;
  border-top: 1px solid var(--border-color);
  padding: 3.5rem 0 2.5rem 0;
}

.footer-nav-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2rem;
  text-align: center;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 1.25rem;
  font-weight: 800;
}

/* 严格限定：只包含 4 个链接标题 */
.footer-four-links {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2.5rem;
  list-style: none;
  flex-wrap: wrap;
}

.footer-link-item a {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-main);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-color);
  transition: all 0.25s ease;
}

.footer-link-item a:hover {
  color: var(--accent-cyan);
  border-color: var(--accent-cyan);
  background: rgba(0, 242, 254, 0.08);
}

.footer-copyright {
  font-size: 0.85rem;
  color: var(--text-dim);
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 1.75rem;
  width: 100%;
}

/* ==========================================================================
   10. 独立二级子页面通用样式 (Page Layout for Subpages)
   ========================================================================== */
.page-hero {
  padding: 4rem 0 2rem 0;
  text-align: center;
  border-bottom: 1px solid var(--border-color);
  background: var(--bg-secondary);
}

.page-title {
  font-size: 2.5rem;
  font-weight: 900;
  margin-bottom: 0.75rem;
}

.page-content {
  padding: 4rem 0;
  max-width: 850px;
  margin: 0 auto;
}

.content-block {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  margin-bottom: 2rem;
}

.content-block h2 {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--accent-cyan);
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.content-block p {
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 1.25rem;
  font-size: 1rem;
}

.content-block ul {
  list-style: none;
  margin-bottom: 1.25rem;
}

.content-block ul li {
  position: relative;
  padding-left: 1.5rem;
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 0.5rem;
}

.content-block ul li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--accent-cyan);
  font-weight: bold;
  font-size: 1.2rem;
}

/* 网站地图层级样式 */
.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.75rem;
}

.sitemap-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.75rem;
}

.sitemap-card h3 {
  font-size: 1.2rem;
  color: var(--accent-cyan);
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.5rem;
}

.sitemap-list {
  list-style: none;
}

.sitemap-list li {
  margin-bottom: 0.6rem;
}

.sitemap-list a {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.sitemap-list a:hover {
  color: var(--accent-cyan);
  padding-left: 4px;
}

/* ==========================================================================
   11. 响应式适配 (Media Queries for Mobile & Tablet)
   ========================================================================== */
@media (max-width: 992px) {
  .hero-title {
    font-size: 2.75rem;
  }
  
  .grid-3, .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .unlock-grid {
    grid-template-columns: 1fr;
  }

  .price-card.popular {
    transform: none;
  }
}

@media (max-width: 768px) {
  .site-header {
    padding: 0.75rem 0;
  }
  
  .nav-menu {
    display: none; /* 移动端隐藏冗余菜单，保留核心 CTA */
  }

  .hero {
    padding: 3rem 0 2.5rem 0;
  }

  .hero-title {
    font-size: 2.1rem;
  }

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

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

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

  .hero-features-strip {
    flex-direction: column;
    gap: 0.85rem;
    align-items: flex-start;
  }

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

  .grid-3, .grid-4, .pricing-grid, .sitemap-grid {
    grid-template-columns: 1fr; /* 完美单栏排列 */
    gap: 1.25rem;
  }

  .price-card {
    padding: 2rem 1.5rem;
  }

  .footer-four-links {
    flex-direction: column;
    gap: 0.85rem;
    width: 100%;
  }

  .footer-link-item {
    width: 100%;
  }

  .footer-link-item a {
    display: block;
    width: 100%;
  }

  .cta-box {
    padding: 2.5rem 1.25rem;
  }

  .cta-box h2 {
    font-size: 1.75rem;
  }
}