/* ==========================================================================
   ToLink加速器 - 极简高性能纯原生 CSS
   特点：零外部依赖、秒级首屏加载、深色高质感科技风、全设备响应式
   ========================================================================== */

:root {
  --bg-primary: #0A0F1E;
  --bg-secondary: #101830;
  --bg-card: rgba(16, 24, 48, 0.78);
  --bg-card-hover: rgba(24, 36, 70, 0.92);
  --border-color: rgba(76, 141, 255, 0.18);
  --border-highlight: #4C8DFF;
  
  --text-main: #FFFFFF;
  --text-muted: #94A3B8;
  --text-dim: #8B9BB4; /* 调优至 5.1:1 对比度，严格符合 WCAG 2.1 AA 标准 */
  
  --primary: #4C8DFF;
  --primary-light: #60A5FA;
  --primary-gradient: linear-gradient(135deg, #4C8DFF 0%, #1D4ED8 100%);
  --accent-cyan: #4C8DFF;
  --accent-glow: rgba(76, 141, 255, 0.45);
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --transition: all 0.28s cubic-bezier(0.16, 1, 0.3, 1);
}

/* 键盘可访问性：无障碍“跳转到主要内容”跳跃链接 */
.skip-link {
  position: absolute;
  top: -120px;
  left: 20px;
  background: var(--primary);
  color: #FFFFFF !important;
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  font-weight: 700;
  text-decoration: none !important;
  z-index: 9999;
  transition: top 0.2s ease;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.5);
}

.skip-link:focus {
  top: 20px;
}

/* 键盘访问焦点轮廓指示器 */
:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 3px;
}

/* 固定页眉防遮挡锚点滚动外边距 */
section, [id] {
  scroll-margin-top: 84px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.6;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 15% 10%, rgba(79, 70, 229, 0.12) 0%, transparent 40%),
    radial-gradient(circle at 85% 30%, rgba(6, 182, 212, 0.08) 0%, transparent 45%);
}

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

img, svg {
  display: block;
}

.container {
  width: 100%;
  max-width: 1180px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

/* 头部导航 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 15, 30, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  padding: 16px 0;
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.35rem;
  font-weight: 900;
  letter-spacing: -0.5px;
  color: #ffffff;
}

.brand-logo .logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, #4C8DFF 0%, #1D4ED8 100%);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  box-shadow: 0 0 18px var(--accent-glow);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

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

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

/* 通用按钮规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 26px;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  white-space: nowrap;
  transition: var(--transition);
  min-height: 46px;
}

.btn-primary {
  background: var(--primary-gradient);
  color: #ffffff;
  box-shadow: 0 4px 20px rgba(79, 70, 229, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(99, 102, 241, 0.55);
}

.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);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.1rem;
  min-height: 54px;
}

/* 徽章 Badge */
.pill-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: rgba(99, 102, 241, 0.12);
  border: 1px solid rgba(99, 102, 241, 0.3);
  border-radius: var(--radius-full);
  color: #a5b4fc;
  font-size: 0.85rem;
  font-weight: 500;
  margin-bottom: 20px;
}

.pill-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #22c55e;
  box-shadow: 0 0 10px #22c55e;
}

/* Hero 主视觉区 */
.hero-section {
  padding: 85px 0 60px;
  text-align: center;
  position: relative;
}

.hero-content {
  max-width: 820px;
  margin: 0 auto;
}

.hero-title {
  font-size: 3.2rem;
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: -1px;
  margin-bottom: 22px;
}

.hero-gradient-text {
  background: linear-gradient(120deg, #ffffff 20%, #a5b4fc 60%, #38bdf8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 36px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 28px;
  flex-wrap: wrap;
}

/* 主视觉区产品简介卡片 */
.hero-intro-card {
  background: rgba(17, 24, 39, 0.7);
  border: 1px solid rgba(99, 102, 241, 0.25);
  border-radius: var(--radius-md);
  padding: 22px 28px;
  max-width: 760px;
  margin: 0 auto 30px;
  text-align: left;
  backdrop-filter: blur(8px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
  position: relative;
}

.hero-intro-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
  font-weight: 700;
  font-size: 1rem;
  color: #a5b4fc;
}

.hero-intro-badge {
  background: rgba(99, 102, 241, 0.2);
  color: #818cf8;
  font-size: 0.75rem;
  padding: 2px 10px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(99, 102, 241, 0.4);
}

.hero-intro-text {
  color: #cbd5e1;
  font-size: 0.95rem;
  line-height: 1.7;
  margin: 0;
}

.hero-guarantee {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  color: var(--text-dim);
  font-size: 0.88rem;
}

.hero-guarantee span {
  display: flex;
  align-items: center;
  gap: 6px;
}

/* 通用章节容器 */
.section {
  padding: 80px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 52px;
}

.section-tag {
  color: var(--accent-cyan);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  margin-bottom: 10px;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 14px;
}

.section-desc {
  color: var(--text-muted);
  font-size: 1.05rem;
}

/* 核心优势卡片（3个图文卡片） */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 30px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-highlight);
  transform: translateY(-5px);
  box-shadow: 0 16px 35px rgba(0, 0, 0, 0.4);
}

.feature-icon-wrapper {
  width: 58px;
  height: 58px;
  background: rgba(99, 102, 241, 0.12);
  border: 1px solid rgba(99, 102, 241, 0.25);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #818cf8;
  margin-bottom: 24px;
}

.feature-card h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* 流媒体与 AI 支持图卡 */
.media-ai-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.media-ai-card {
  background: linear-gradient(180deg, rgba(23, 31, 51, 0.7) 0%, rgba(15, 23, 42, 0.9) 100%);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  position: relative;
  overflow: hidden;
}

.media-ai-card.highlight-ai {
  border-color: rgba(6, 182, 212, 0.3);
}

.card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 20px;
}

.card-badge {
  font-size: 0.78rem;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  background: rgba(99, 102, 241, 0.15);
  color: #a5b4fc;
  border: 1px solid rgba(99, 102, 241, 0.3);
}

.card-badge.cyan {
  background: rgba(6, 182, 212, 0.15);
  color: #67e8f9;
  border-color: rgba(6, 182, 212, 0.3);
}

.media-ai-card h3 {
  font-size: 1.45rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.media-ai-card .card-summary {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 26px;
}

.platform-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  color: #e2e8f0;
  font-weight: 500;
}

.chip-status {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #10b981;
}

/* 套餐价格对比表 */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 38px 28px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: var(--transition);
}

.pricing-card:hover {
  transform: translateY(-6px);
  border-color: rgba(255, 255, 255, 0.2);
}

.pricing-card.featured {
  background: linear-gradient(180deg, rgba(30, 41, 75, 0.9) 0%, rgba(15, 23, 42, 0.95) 100%);
  border: 2px solid var(--primary-light);
  box-shadow: 0 10px 40px rgba(79, 70, 229, 0.25);
  transform: scale(1.03);
}

.pricing-card.featured:hover {
  transform: scale(1.05) translateY(-6px);
}

.popular-tag {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary-gradient);
  color: #ffffff;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: var(--radius-full);
  letter-spacing: 0.5px;
  box-shadow: 0 4px 12px rgba(79, 70, 229, 0.5);
}

.pricing-header {
  margin-bottom: 20px;
}

.plan-name {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.plan-desc {
  color: var(--text-muted);
  font-size: 0.88rem;
  min-height: 42px;
}

.pricing-price {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-bottom: 26px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
}

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

.amount {
  font-size: 2.8rem;
  font-weight: 800;
  color: #ffffff;
  letter-spacing: -1px;
}

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

.pricing-features {
  list-style: none;
  margin-bottom: 32px;
  flex-grow: 1;
}

.pricing-features li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.92rem;
  color: #cbd5e1;
  margin-bottom: 14px;
}

.pricing-features svg {
  flex-shrink: 0;
  margin-top: 3px;
  color: #22c55e;
}

.pricing-card .btn {
  width: 100%;
}

/* 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-lg);
  padding: 30px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.stars {
  display: flex;
  gap: 4px;
  color: #f59e0b;
  margin-bottom: 16px;
}

.review-text {
  color: #cbd5e1;
  font-size: 0.95rem;
  line-height: 1.65;
  margin-bottom: 22px;
  font-style: italic;
}

.reviewer-meta {
  display: flex;
  align-items: center;
  gap: 12px;
}

.avatar-initial {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: rgba(99, 102, 241, 0.2);
  border: 1px solid rgba(99, 102, 241, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #a5b4fc;
  font-size: 1rem;
}

.reviewer-info h4 {
  font-size: 0.95rem;
  font-weight: 600;
}

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

/* FAQ 常见问题 (使用纯 HTML details/summary 实现零 JS 原生交互) */
.faq-list {
  max-width: 820px;
  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-item:hover {
  border-color: rgba(255, 255, 255, 0.2);
}

.faq-item[open] {
  border-color: var(--border-highlight);
  background: rgba(24, 32, 52, 0.8);
}

.faq-question {
  padding: 20px 24px;
  font-size: 1.05rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  list-style: none;
  user-select: none;
}

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

.faq-icon {
  width: 20px;
  height: 20px;
  color: var(--text-muted);
  transition: transform 0.25s ease;
  flex-shrink: 0;
}

.faq-item[open] .faq-icon {
  transform: rotate(180deg);
  color: #818cf8;
}

.faq-answer {
  padding: 0 24px 22px;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
  border-top: 1px solid rgba(255, 255, 255, 0.04);
  padding-top: 16px;
}

/* 底部 CTA 区域 */
.cta-banner {
  margin: 80px 0 40px;
  background: radial-gradient(circle at 50% 50%, rgba(79, 70, 229, 0.25) 0%, rgba(17, 24, 39, 0.9) 100%);
  border: 1px solid rgba(99, 102, 241, 0.35);
  border-radius: var(--radius-lg);
  padding: 60px 30px;
  text-align: center;
}

.cta-banner h2 {
  font-size: 2.4rem;
  font-weight: 800;
  margin-bottom: 16px;
}

.cta-banner p {
  color: var(--text-muted);
  font-size: 1.1rem;
  margin-bottom: 30px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* 页脚规范：严格只保留 4 个标题链接并新开窗口 */
.site-footer {
  background: #070a10;
  border-top: 1px solid var(--border-color);
  padding: 50px 0 40px;
}

.footer-nav-list {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  list-style: none;
  margin-bottom: 28px;
  flex-wrap: wrap;
}

.footer-nav-list a {
  color: #cbd5e1;
  font-size: 1rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.footer-nav-list a:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.05);
  text-decoration: underline;
}

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

/* 子页面内容排版通用样式 (关于我们、服务条款、隐私政策、网站地图) */
.subpage-hero {
  padding: 60px 0 40px;
  text-align: center;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 50px;
}

.subpage-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 14px;
}

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

.legal-content, .about-content, .sitemap-content {
  max-width: 860px;
  margin: 0 auto 80px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 45px;
}

.content-block {
  margin-bottom: 36px;
}

.content-block:last-child {
  margin-bottom: 0;
}

.content-block h2 {
  font-size: 1.45rem;
  color: #ffffff;
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 10px;
  border-left: 4px solid var(--primary-light);
  padding-left: 14px;
}

.content-block p {
  color: var(--text-muted);
  font-size: 0.98rem;
  line-height: 1.8;
  margin-bottom: 12px;
}

.content-block ul {
  padding-left: 20px;
  color: var(--text-muted);
  font-size: 0.98rem;
  line-height: 1.8;
}

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

.back-home-bar {
  margin-bottom: 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

/* 网站地图专用列表 */
.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.sitemap-card {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
}

.sitemap-card h3 {
  font-size: 1.15rem;
  margin-bottom: 12px;
  color: #a5b4fc;
}

.sitemap-card ul {
  list-style: none;
  padding: 0;
}

.sitemap-card li {
  margin-bottom: 10px;
}

.sitemap-card a {
  color: #e2e8f0;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.sitemap-card a:hover {
  color: var(--accent-cyan);
}

/* ==========================================================================
   响应式媒体查询 (@media) - 确保手机端完美单栏自适应
   ========================================================================== */
@media (max-width: 992px) {
  .hero-title {
    font-size: 2.6rem;
  }
  
  .features-grid,
  .pricing-grid,
  .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .pricing-card.featured {
    transform: none;
  }
  
  .pricing-card.featured:hover {
    transform: translateY(-6px);
  }
}

@media (max-width: 768px) {
  .hero-section {
    padding: 50px 0 40px;
  }

  .hero-title {
    font-size: 2.05rem;
    line-height: 1.25;
  }

  .hero-subtitle {
    font-size: 1rem;
    margin-bottom: 28px;
  }

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

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

  .hero-guarantee {
    flex-direction: column;
    gap: 10px;
  }

  /* 核心栅格转单栏 */
  .features-grid,
  .media-ai-grid,
  .pricing-grid,
  .reviews-grid,
  .sitemap-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .section {
    padding: 55px 0;
  }

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

  .section-header {
    margin-bottom: 36px;
  }

  .feature-card,
  .media-ai-card,
  .pricing-card,
  .review-card {
    padding: 26px 20px;
  }

  .pricing-card.featured {
    order: -1; /* 手机端优先展示主推款 */
  }

  .cta-banner {
    padding: 40px 20px;
    margin: 50px 0 20px;
  }

  .cta-banner h2 {
    font-size: 1.8rem;
  }

  /* 页脚单栏或紧凑排版 */
  .footer-nav-list {
    flex-direction: column;
    gap: 16px;
  }

  .nav-links {
    display: none; /* 移动端精简头部，直接突出右上角立即体验 */
  }

  .legal-content, .about-content, .sitemap-content {
    padding: 24px 18px;
  }
}

/* 移动端触控靶区优化：确保所有按钮触控区域至少 44×44 CSS 像素 */
@media (max-width: 768px) {
  .btn, .btn-primary, .btn-secondary, button {
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .footer-nav-list a {
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    padding: 6px 0;
  }
}

/* 无障碍：减少动态效果偏好响应 (prefers-reduced-motion) */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  
  #space-canvas {
    display: none !important;
  }
}