/* ==========================================================================
   老猫云 (ioldcatyun.click) - 全局原生 CSS 样式表
   视觉风格：星云极光与电光幻紫 (Nebula Aurora & Electric Violet-Cyan)
   代码极简、纯原生 CSS、零外部库、秒开级性能、无障碍优先与移动端极致适配
   ========================================================================== */

:root {
  /* 老猫云 .click 专属视觉体系：星云深空黑夜、电光幻紫与极光冰蓝 */
  --bg-primary: #070913;
  --bg-secondary: #0d1124;
  --bg-tertiary: #131936;
  --bg-card: rgba(16, 22, 48, 0.72);
  --bg-card-hover: rgba(23, 31, 68, 0.88);
  --bg-glass: rgba(13, 17, 36, 0.88);
  --bg-accent-soft: rgba(99, 102, 241, 0.1);

  /* 边框与流光描边系统 */
  --border-color: rgba(99, 102, 241, 0.22);
  --border-hover: rgba(6, 182, 212, 0.55);
  --border-accent: rgba(168, 85, 247, 0.6);
  --border-highlight: rgba(255, 255, 255, 0.15);
  --border-subtle: rgba(255, 255, 255, 0.08);

  /* 文字对比度规范 (正文 >= 4.5:1，核心标题 >= 7:1) */
  --text-main: #f8fafc;
  --text-light: #e2e8f0;
  --text-muted: #94a3b8;
  --text-dim: #64748b;

  /* 品牌核心色彩：电光紫 (Electric Indigo/Violet) 与 极光青 (Aurora Cyan) */
  --color-primary: #6366f1;
  --color-primary-rgb: 99, 102, 241;
  --color-primary-dark: #4f46e5;
  --color-accent: #06b6d4;
  --color-accent-rgb: 6, 182, 212;
  --color-secondary: #a855f7;
  --color-glow: #38bdf8;
  --color-success: #10b981;
  --color-tag-bg: rgba(99, 102, 241, 0.14);

  /* 专属流光渐变体系 */
  --color-gradient: linear-gradient(135deg, #6366f1 0%, #a855f7 50%, #06b6d4 100%);
  --color-gradient-cyan: linear-gradient(135deg, #06b6d4 0%, #3b82f6 50%, #8b5cf6 100%);
  --color-gradient-hover: linear-gradient(135deg, #818cf8 0%, #c084fc 50%, #22d3ee 100%);
  --color-btn-glow: linear-gradient(135deg, rgba(99, 102, 241, 0.6) 0%, rgba(168, 85, 247, 0.45) 100%);
  --color-card-border: linear-gradient(135deg, rgba(99, 102, 241, 0.35) 0%, rgba(6, 182, 212, 0.25) 100%);

  /* 光影与景深系统 */
  --shadow-sm: 0 4px 16px rgba(0, 0, 0, 0.45);
  --shadow-md: 0 10px 30px -5px rgba(0, 0, 0, 0.7), 0 0 1px 1px rgba(255, 255, 255, 0.06);
  --shadow-lg: 0 20px 45px -10px rgba(0, 0, 0, 0.85), 0 0 28px rgba(99, 102, 241, 0.2);
  --shadow-glow: 0 0 32px rgba(99, 102, 241, 0.35);
  --shadow-glow-strong: 0 0 48px rgba(99, 102, 241, 0.55);

  /* 几何圆角体系 */
  --radius-xs: 6px;
  --radius-sm: 10px;
  --radius-md: 18px;
  --radius-lg: 26px;
  --radius-full: 9999px;

  /* 布局与动画基准 */
  --container-width: 1200px;
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  --header-height: 72px;
}

/* ==========================================================================
   全局重置与排版规范
   ========================================================================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "WenQuanYi Micro Hei", sans-serif;
  background-color: var(--bg-primary);
  background-image: 
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(99, 102, 241, 0.18), transparent 70%),
    radial-gradient(circle 600px at 90% 20%, rgba(6, 182, 212, 0.1), transparent 70%),
    radial-gradient(circle 500px at 10% 60%, rgba(168, 85, 247, 0.08), transparent 60%);
  background-attachment: fixed;
  color: var(--text-light);
  line-height: 1.68;
  letter-spacing: 0.01em;
  overflow-x: hidden;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* 锚点定位避免固定页眉遮挡 */
[id] {
  scroll-margin-top: calc(var(--header-height) + 24px);
}

/* 无障碍键盘直达入口 */
.skip-link {
  position: absolute;
  top: -100px;
  left: 20px;
  background: var(--color-primary);
  color: #fff;
  padding: 10px 20px;
  z-index: 99999;
  font-weight: 700;
  border-radius: var(--radius-xs);
  text-decoration: none;
  transition: top var(--transition-fast);
  box-shadow: var(--shadow-md);
}
.skip-link:focus {
  top: 16px;
  outline: 3px solid #fff;
}

/* 容器与版心限制 */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* 链接基础样式 */
a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}
a:hover {
  color: #67e8f9;
}
a:focus-visible, button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 4px;
}

/* ==========================================================================
   全局固定页眉与导航
   ========================================================================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: var(--bg-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  display: flex;
  align-items: center;
  transition: background var(--transition-normal), border var(--transition-normal);
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.01em;
}
.brand-logo:hover {
  color: #fff;
}
.brand-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.25) 0%, rgba(6, 182, 212, 0.2) 100%);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  font-size: 1.4rem;
  box-shadow: 0 0 12px rgba(99, 102, 241, 0.25);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}
.main-nav a {
  color: var(--text-light);
  font-size: 0.96rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: var(--radius-xs);
  transition: all var(--transition-fast);
}
.main-nav a:hover {
  color: #fff;
  background: var(--bg-accent-soft);
}
.main-nav .nav-cta {
  background: var(--color-gradient);
  color: #fff !important;
  font-weight: 700;
  padding: 9px 20px;
  border-radius: var(--radius-full);
  box-shadow: 0 4px 18px rgba(99, 102, 241, 0.35);
}
.main-nav .nav-cta:hover {
  background: var(--color-gradient-hover);
  box-shadow: 0 6px 24px rgba(99, 102, 241, 0.55);
  transform: translateY(-1px);
}

/* ==========================================================================
   按钮基础系统规范 (确保移动端 44x44px 以上触摸面积)
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 28px;
  font-size: 1rem;
  font-weight: 700;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition-normal);
  border: 1px solid transparent;
  text-align: center;
  white-space: nowrap;
  user-select: none;
}

.btn-primary {
  background: var(--color-gradient);
  color: #ffffff !important;
  border: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: 0 8px 24px rgba(99, 102, 241, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.2);
}
.btn-primary:hover {
  background: var(--color-gradient-hover);
  box-shadow: 0 12px 32px rgba(99, 102, 241, 0.6), inset 0 1px 0 rgba(255, 255, 255, 0.3);
  transform: translateY(-2px);
}

.btn-secondary {
  background: rgba(16, 22, 48, 0.7);
  color: var(--text-main) !important;
  border: 1px solid var(--border-color);
  backdrop-filter: blur(8px);
}
.btn-secondary:hover {
  background: rgba(30, 41, 86, 0.85);
  border-color: var(--color-primary);
  color: #ffffff !important;
  transform: translateY(-2px);
}

.btn-sm {
  min-height: 40px;
  padding: 8px 18px;
  font-size: 0.9rem;
  border-radius: var(--radius-full);
}

/* ==========================================================================
   主视觉区 (Hero Section)
   ========================================================================== */
.hero-section {
  padding-top: calc(var(--header-height) + 56px);
  padding-bottom: 72px;
  text-align: center;
  position: relative;
}

.badge-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 18px;
  background: rgba(99, 102, 241, 0.12);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  color: #a5b4fc;
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(2.2rem, 5vw, 3.6rem);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: -0.02em;
  color: var(--text-main);
  margin-bottom: 20px;
}

.gradient-text {
  background: var(--color-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.hero-subtitle {
  font-size: clamp(1.1rem, 2.2vw, 1.45rem);
  color: #c7d2fe;
  font-weight: 500;
  margin-bottom: 18px;
  max-width: 820px;
  margin-left: auto;
  margin-right: auto;
}

.hero-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 780px;
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 36px;
  line-height: 1.75;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 48px;
}

.hero-highlights {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 32px;
  flex-wrap: wrap;
  padding: 22px 32px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
  backdrop-filter: blur(12px);
  box-shadow: var(--shadow-sm);
}
.hero-highlights span {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.95rem;
  color: var(--text-light);
  font-weight: 500;
}

/* ==========================================================================
   内容分块与区块标题系统
   ========================================================================== */
.section {
  padding: 72px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 52px;
}
.section-subtitle {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--color-accent);
  margin-bottom: 8px;
}
.section-title {
  font-size: clamp(1.8rem, 3.5vw, 2.4rem);
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 14px;
  line-height: 1.28;
}
.section-desc {
  font-size: 1.02rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ==========================================================================
   产品核心优势卡片 (3 个图文卡片)
   ========================================================================== */
.grid-3 {
  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-md);
  padding: 36px 30px;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--color-gradient);
  opacity: 0;
  transition: opacity var(--transition-normal);
}
.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}
.feature-card:hover::before {
  opacity: 1;
}

.feature-icon-wrapper {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.2) 0%, rgba(6, 182, 212, 0.15) 100%);
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  margin-bottom: 24px;
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.25);
}

.feature-title {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 14px;
}

.feature-text {
  font-size: 0.96rem;
  color: var(--text-muted);
  line-height: 1.75;
}

/* ==========================================================================
   流媒体与 AI 支持图卡
   ========================================================================== */
.media-ai-container {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}

.media-ai-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 36px;
  position: relative;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
}
.media-ai-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.media-ai-badge {
  display: inline-block;
  padding: 4px 14px;
  background: rgba(6, 182, 212, 0.12);
  border: 1px solid rgba(6, 182, 212, 0.3);
  color: var(--color-accent);
  font-size: 0.82rem;
  font-weight: 700;
  border-radius: var(--radius-full);
  margin-bottom: 18px;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.tag-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  color: var(--text-light);
  font-weight: 500;
}
.tag-item:hover {
  background: rgba(99, 102, 241, 0.12);
  border-color: var(--border-color);
  color: #fff;
}

/* ==========================================================================
   套餐价格对比表 (规范 Table 语义与横向滚动自适应)
   ========================================================================== */
.pricing-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow-md);
  backdrop-filter: blur(16px);
}

.pricing-table-container {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.pricing-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  min-width: 720px;
  text-align: left;
}

.pricing-table caption {
  font-size: 0.95rem;
  color: var(--text-dim);
  text-align: right;
  margin-bottom: 16px;
  font-style: italic;
}

.pricing-table th,
.pricing-table td {
  padding: 20px 22px;
  border-bottom: 1px solid var(--border-subtle);
  vertical-align: middle;
}

.pricing-table th {
  background: rgba(13, 17, 36, 0.8);
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  border-bottom: 2px solid var(--border-color);
}

.pricing-table tr:hover td {
  background: rgba(99, 102, 241, 0.06);
}

.plan-name {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--text-main);
  display: block;
}
.plan-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
}
.plan-price {
  font-size: 1.45rem;
  font-weight: 900;
  color: #a5b4fc;
}
.plan-price small {
  font-size: 0.85rem;
  font-weight: 400;
  color: var(--text-muted);
}
.popular-badge {
  display: inline-block;
  padding: 3px 10px;
  font-size: 0.75rem;
  font-weight: 700;
  background: var(--color-gradient);
  color: #fff;
  border-radius: var(--radius-full);
  margin-left: 8px;
  vertical-align: middle;
}

/* ==========================================================================
   用户评价区块 (Testimonials)
   ========================================================================== */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
}
.review-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-4px);
}

.review-stars {
  color: #38bdf8;
  font-size: 1.1rem;
  letter-spacing: 2px;
  margin-bottom: 16px;
}

.review-content {
  font-size: 0.96rem;
  color: var(--text-light);
  line-height: 1.75;
  margin-bottom: 24px;
}

.review-user {
  display: flex;
  align-items: center;
  gap: 14px;
  border-top: 1px solid var(--border-subtle);
  padding-top: 18px;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, #6366f1 0%, #06b6d4 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #fff;
  font-size: 1.1rem;
}

.user-name {
  font-weight: 700;
  color: var(--text-main);
  font-size: 0.98rem;
}
.user-tag {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* ==========================================================================
   常见问题解答 (FAQ) 原生 details / summary 规范化设计
   所有 FAQ 默认展开 open
   ========================================================================== */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
  max-width: 920px;
  margin: 0 auto;
}

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

.faq-item[open] {
  border-color: rgba(99, 102, 241, 0.45);
  background: rgba(19, 26, 56, 0.85);
}

.faq-question {
  padding: 22px 28px;
  font-size: 1.12rem;
  font-weight: 700;
  color: var(--text-main);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  user-select: none;
}
.faq-question::-webkit-details-marker {
  display: none;
}
.faq-question::after {
  content: "＋";
  font-size: 1.35rem;
  font-weight: 400;
  color: var(--color-accent);
  transition: transform var(--transition-fast);
}
.faq-item[open] .faq-question::after {
  content: "－";
  color: #a5b4fc;
}

.faq-answer {
  padding: 0 28px 24px;
  color: var(--text-muted);
  font-size: 0.98rem;
  line-height: 1.78;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 18px;
}
.faq-answer a {
  color: #38bdf8;
  text-decoration: underline;
  text-underline-offset: 4px;
}
.faq-answer a:hover {
  color: #fff;
}

/* ==========================================================================
   知识科普文章与列表专栏布局
   ========================================================================== */
.knowledge-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin-top: 36px;
}

.knowledge-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;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-sm);
}
.knowledge-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}
.knowledge-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.45;
  margin-bottom: 14px;
}
.knowledge-card h3 a {
  color: var(--text-main);
}
.knowledge-card h3 a:hover {
  color: #67e8f9;
}
.knowledge-card p {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.68;
  margin-bottom: 20px;
}
.knowledge-card .read-more {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* 面包屑导航 */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  color: var(--text-dim);
  margin-bottom: 24px;
}
.breadcrumb a {
  color: var(--text-muted);
}
.breadcrumb a:hover {
  color: var(--color-accent);
}

/* 文章详情页主体 */
.article-header {
  padding-top: calc(var(--header-height) + 40px);
  padding-bottom: 24px;
  max-width: 860px;
  margin: 0 auto;
}
.article-title {
  font-size: clamp(1.8rem, 3.5vw, 2.4rem);
  font-weight: 800;
  color: var(--text-main);
  line-height: 1.3;
  margin-bottom: 18px;
}
.article-meta {
  display: flex;
  gap: 20px;
  font-size: 0.88rem;
  color: var(--text-dim);
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
}
.article-body {
  max-width: 860px;
  margin: 0 auto;
  padding: 32px 0 64px;
  font-size: 1.05rem;
  line-height: 1.85;
  color: var(--text-light);
}
.article-body h2 {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--text-main);
  margin: 40px 0 18px;
  padding-left: 14px;
  border-left: 4px solid var(--color-primary);
}
.article-body h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: #e2e8f0;
  margin: 28px 0 14px;
}
.article-body p {
  margin-bottom: 20px;
}
.article-body ul, .article-body ol {
  margin: 0 0 24px 24px;
}
.article-body li {
  margin-bottom: 10px;
  color: var(--text-muted);
}
.article-body li strong {
  color: var(--text-main);
}
.article-callout {
  background: rgba(99, 102, 241, 0.1);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px;
  margin: 36px 0;
  text-align: center;
}
.article-callout h4 {
  font-size: 1.25rem;
  color: var(--text-main);
  margin-bottom: 10px;
}
.article-callout p {
  color: var(--text-muted);
  margin-bottom: 20px;
}

/* ==========================================================================
   页脚规范 (严格只保留四个链接打开新页面展示)
   ========================================================================== */
.site-footer {
  margin-top: auto;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 48px 0 36px;
  text-align: center;
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 36px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

.footer-nav a {
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--text-muted);
  transition: color var(--transition-fast);
}
.footer-nav a:hover {
  color: #38bdf8;
}

.footer-copy {
  font-size: 0.88rem;
  color: var(--text-dim);
  line-height: 1.6;
}

/* ==========================================================================
   响应式媒体查询 (@media) 严格适配 360 / 390 / 768 / 1440 像素
   ========================================================================== */
@media (max-width: 1024px) {
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
  .knowledge-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  :root {
    --header-height: 64px;
  }
  .site-header .container {
    padding-left: 16px;
    padding-right: 16px;
  }
  .brand-logo {
    font-size: 1.15rem;
  }
  .main-nav {
    gap: 12px;
  }
  .main-nav a {
    font-size: 0.88rem;
    padding: 6px 8px;
  }
  .main-nav .nav-cta {
    padding: 6px 14px;
  }

  .grid-3,
  .media-ai-container,
  .reviews-grid,
  .knowledge-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .hero-section {
    padding-top: calc(var(--header-height) + 32px);
    padding-bottom: 48px;
  }
  .hero-highlights {
    flex-direction: column;
    gap: 16px;
    align-items: flex-start;
    padding: 20px;
  }

  .pricing-wrapper {
    padding: 20px 14px;
  }
  .pricing-table th,
  .pricing-table td {
    padding: 14px 12px;
  }

  .footer-nav {
    gap: 20px;
  }
}

@media (max-width: 480px) {
  .hero-cta-group {
    flex-direction: column;
    width: 100%;
  }
  .hero-cta-group .btn {
    width: 100%;
  }
  .faq-question {
    padding: 18px 20px;
    font-size: 1rem;
  }
  .faq-answer {
    padding: 0 20px 18px;
    font-size: 0.92rem;
  }
}

/* 尊重用户偏好动画减少 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}