/* ==========================================================================
   贝贝云 (beibeiyun.site) 极简原生样式表
   无外部框架依赖 / 极致秒开 / 响应式适配 / 无障碍对比度 >= 4.5:1
   ========================================================================== */

:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-dark: #1e40af;
  --primary-light: #eff6ff;
  --accent: #f59e0b;
  --accent-hover: #d97706;
  --text-main: #0f172a;
  --text-muted: #475569;
  --text-light: #64748b;
  --bg-body: #f8fafc;
  --bg-card: #ffffff;
  --bg-alt: #f1f5f9;
  --border-color: #e2e8f0;
  --border-focus: #3b82f6;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.08), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.03);
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "WenQuanYi Micro Hei", sans-serif;
  --max-width: 1200px;
  --header-height: 70px;
}

/* 全局重置与无障碍 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-main);
  background-color: var(--bg-body);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* 锚点偏移防遮挡 */
[id] {
  scroll-margin-top: calc(var(--header-height) + 20px);
}

/* 键盘跳跃链接 */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  background: var(--primary);
  color: #ffffff;
  padding: 0.75rem 1.5rem;
  z-index: 9999;
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-weight: 600;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 1rem;
  outline: 3px solid var(--accent);
}

/* 容器与通用排版 */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--primary-hover);
  text-decoration: underline;
}

a:focus-visible, button:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

h1, h2, h3, h4 {
  color: var(--text-main);
  line-height: 1.3;
  font-weight: 700;
}

h1 { font-size: 2.25rem; }
h2 { font-size: 1.85rem; margin-bottom: 1rem; text-align: center; }
h3 { font-size: 1.35rem; margin-bottom: 0.5rem; }
p { margin-bottom: 1rem; color: var(--text-muted); }

/* 顶栏与导航 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border-color);
  height: var(--header-height);
  display: flex;
  align-items: center;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--primary);
  text-decoration: none;
}

.brand-logo svg {
  width: 34px;
  height: 34px;
  flex-shrink: 0;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-link {
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 0.5rem;
  border-radius: var(--radius-sm);
  text-decoration: none;
}

.nav-link:hover, .nav-link.active {
  color: var(--primary);
  text-decoration: none;
}

.nav-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--primary);
  color: #ffffff !important;
  font-weight: 600;
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius-md);
  min-height: 44px;
  min-width: 44px;
  text-decoration: none;
  transition: background-color 0.2s ease, transform 0.1s ease;
}

.nav-btn:hover {
  background-color: var(--primary-hover);
  text-decoration: none;
  transform: translateY(-1px);
}

/* 按钮通用规范 (满足 >= 44x44px 触摸要求) */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-size: 1rem;
  font-weight: 600;
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius-md);
  min-height: 44px;
  min-width: 44px;
  cursor: pointer;
  text-decoration: none;
  border: none;
  white-space: nowrap;
  word-break: keep-all;
  transition: all 0.2s ease;
}

.btn-primary {
  background-color: var(--primary);
  color: #ffffff;
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  color: #ffffff;
  text-decoration: none;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
}

.btn-accent {
  background-color: var(--accent);
  color: #ffffff;
}

.btn-accent:hover {
  background-color: var(--accent-hover);
  color: #ffffff;
  text-decoration: none;
  box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
}

.btn-outline {
  background-color: transparent;
  color: var(--primary);
  border: 1px solid var(--primary);
}

.btn-outline:hover {
  background-color: var(--primary-light);
  text-decoration: none;
}

/* Hero 主视觉区 - 海水沙滩涨退动态场景 */
.hero-section {
  position: relative;
  overflow: hidden;
  padding: 4.5rem 0 6rem;
  text-align: center;
  background: linear-gradient(180deg, #f0f9ff 0%, #e0f2fe 45%, #bae6fd 70%, #fed7aa 100%);
  border-bottom: 1px solid #fcd34d;
}

.hero-content {
  position: relative;
  z-index: 5;
}

/* 动态海水沙滩背景图层 */
.hero-beach-backdrop {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 1;
}

/* 海岸晨曦光晕 */
.beach-sun-glow {
  position: absolute;
  top: -60px;
  right: 15%;
  width: 340px;
  height: 340px;
  background: radial-gradient(circle, rgba(254, 240, 138, 0.45) 0%, rgba(253, 186, 116, 0.2) 50%, transparent 70%);
  border-radius: 50%;
  filter: blur(28px);
}

/* 沙滩与海水波浪容器 */
.sea-shore-wrapper {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 180px;
  overflow: hidden;
}

/* 底部柔和金黄色沙滩层 */
.beach-sand-layer {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 75px;
  background: linear-gradient(180deg, rgba(254, 243, 199, 0) 0%, #fef08a 35%, #fde047 65%, #fcd34d 100%);
  z-index: 1;
}

/* 动态波浪 SVG */
.ocean-waves-svg {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 200%;
  height: 100%;
  z-index: 2;
}

.wave-layer {
  transform-origin: center bottom;
  will-change: transform, opacity;
}

/* 第1层：深海平缓波涛 */
.wave-layer-1 {
  animation: waveDeepFlow 16s cubic-bezier(0.36, 0.45, 0.63, 0.53) infinite;
}

/* 第2层：中层碧波涌动 */
.wave-layer-2 {
  animation: waveMidFlow 10s cubic-bezier(0.36, 0.45, 0.63, 0.53) infinite;
}

/* 第3层：海水向沙滩涨起与退下的主力海潮 */
.wave-layer-3 {
  animation: waveEbbAndFlow 6s ease-in-out infinite;
}

/* 第4层：冲上海滩的白沫浪花 */
.wave-layer-foam {
  animation: waveFoamWash 6s ease-in-out infinite;
}

/* 涨退潮关键帧动画 (纯原生 GPU 硬件加速) */
@keyframes waveDeepFlow {
  0% {
    transform: translate3d(0, 0, 0);
  }
  50% {
    transform: translate3d(-25%, 8px, 0);
  }
  100% {
    transform: translate3d(-50%, 0, 0);
  }
}

@keyframes waveMidFlow {
  0% {
    transform: translate3d(-20%, 12px, 0);
  }
  50% {
    transform: translate3d(0, 0, 0);
  }
  100% {
    transform: translate3d(-20%, 12px, 0);
  }
}

/* 核心：海水漫过沙滩（涨潮）与徐徐回落（退潮） */
@keyframes waveEbbAndFlow {
  0% {
    transform: translate3d(-5%, 26px, 0) scaleY(0.85);
  }
  45% {
    transform: translate3d(-20%, -16px, 0) scaleY(1.25);
  }
  65% {
    transform: translate3d(-26%, -10px, 0) scaleY(1.16);
  }
  100% {
    transform: translate3d(-5%, 26px, 0) scaleY(0.85);
  }
}

/* 浪花白沫与浸润效果 */
@keyframes waveFoamWash {
  0% {
    transform: translate3d(-5%, 26px, 0) scaleY(0.85);
    opacity: 0.25;
  }
  45% {
    transform: translate3d(-20%, -18px, 0) scaleY(1.28);
    opacity: 0.95;
  }
  65% {
    transform: translate3d(-26%, -12px, 0) scaleY(1.18);
    opacity: 0.85;
  }
  85% {
    opacity: 0.45;
  }
  100% {
    transform: translate3d(-5%, 26px, 0) scaleY(0.85);
    opacity: 0.25;
  }
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 1rem;
  background-color: #dbeafe;
  color: var(--primary-dark);
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: 9999px;
  margin-bottom: 1.5rem;
}

.hero-title {
  font-size: 2.75rem;
  letter-spacing: -0.02em;
  margin-bottom: 1.25rem;
  color: #0f172a;
}

.hero-title span {
  color: var(--primary);
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-muted);
  max-width: 800px;
  margin: 0 auto 1.5rem;
  line-height: 1.6;
}

.hero-intro {
  font-size: 1rem;
  color: var(--text-light);
  max-width: 720px;
  margin: 0 auto 2rem;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 2rem;
}

.hero-highlights {
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(226, 232, 240, 0.8);
  font-size: 0.9rem;
  color: var(--text-muted);
}

.hero-highlights span {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

/* 区块通用结构 */
.section {
  padding: 4.5rem 0;
}

.section-alt {
  background-color: var(--bg-card);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 3rem;
}

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

/* 核心优势卡片网格 (3个图文卡片) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.25rem 1.75rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  display: flex;
  flex-direction: column;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.feature-icon-wrapper {
  width: 56px;
  height: 56px;
  background-color: var(--primary-light);
  color: var(--primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.25rem;
}

.feature-icon-wrapper svg {
  width: 28px;
  height: 28px;
  fill: currentColor;
}

.feature-title {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
}

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

/* 流媒体与 AI 支持图卡 */
.support-showcase {
  background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
  color: #ffffff;
  border-radius: var(--radius-lg);
  padding: 3rem 2.5rem;
  margin-top: 1.5rem;
  box-shadow: var(--shadow-lg);
}

.support-showcase h3 {
  color: #ffffff;
  font-size: 1.6rem;
  margin-bottom: 1rem;
  text-align: center;
}

.support-showcase p {
  color: #94a3b8;
  text-align: center;
  max-width: 750px;
  margin: 0 auto 2.5rem;
}

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

.support-item {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-md);
  padding: 1.75rem;
}

.support-item h4 {
  color: #38bdf8;
  font-size: 1.15rem;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.support-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.75rem;
}

.support-tag {
  background: rgba(56, 189, 248, 0.15);
  color: #e0f2fe;
  font-size: 0.8rem;
  padding: 0.25rem 0.6rem;
  border-radius: 4px;
}

/* 套餐价格卡片网格 (价格优先醒目展示) */
.pricing-cards-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin-bottom: 2.5rem;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.25rem 1.5rem 1.75rem;
  display: flex;
  flex-direction: column;
  position: relative;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.pricing-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.pricing-card.featured-plan {
  border: 2px solid var(--primary);
  background: linear-gradient(180deg, #ffffff 0%, #eff6ff 100%);
  box-shadow: 0 10px 25px -4px rgba(37, 99, 235, 0.18);
  transform: scale(1.02);
}

.pricing-card.featured-plan:hover {
  transform: scale(1.02) translateY(-4px);
}

.popular-ribbon {
  position: absolute;
  top: -13px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(90deg, #ef4444, #f59e0b);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.3rem 1rem;
  border-radius: 9999px;
  letter-spacing: 0.03em;
  white-space: nowrap;
  box-shadow: 0 2px 8px rgba(239, 68, 68, 0.35);
}

.plan-header {
  text-align: center;
  margin-bottom: 1rem;
}

.plan-title {
  font-size: 1.35rem;
  color: var(--text-main);
  margin-bottom: 0.25rem;
}

.plan-subtitle {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-bottom: 0;
}

/* 核心：价格最优先、超大字号醒目展示 */
.plan-price-box {
  text-align: center;
  padding: 1.15rem 0.5rem;
  margin-bottom: 1.25rem;
  background-color: #f8fafc;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
}

.featured-plan .plan-price-box {
  background-color: #ffffff;
  border-color: #bfdbfe;
}

.plan-price-box .currency {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--primary);
  vertical-align: top;
  line-height: 1.2;
}

.plan-price-box .price-amount {
  font-size: 2.6rem;
  font-weight: 900;
  color: var(--primary);
  line-height: 1;
  letter-spacing: -0.03em;
}

.plan-price-box .price-period {
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 500;
  margin-left: 0.25rem;
}

.plan-cta {
  width: 100%;
  margin-bottom: 1.5rem;
  white-space: nowrap;
  word-break: keep-all;
}

.plan-features {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  font-size: 0.9rem;
  border-top: 1px solid var(--border-color);
  padding-top: 1.25rem;
}

.plan-features li {
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-muted);
  margin-bottom: 0;
}

.plan-features li strong {
  color: var(--text-main);
}

/* 价格套餐对比表 */
.pricing-wrapper {
  overflow-x: auto;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  box-shadow: var(--shadow-sm);
  margin-bottom: 2rem;
}

.pricing-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

.pricing-table caption {
  padding: 1.25rem;
  font-weight: 700;
  font-size: 1.1rem;
  text-align: left;
  background-color: var(--bg-alt);
  border-bottom: 1px solid var(--border-color);
}

.pricing-table th, .pricing-table td {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.95rem;
  white-space: nowrap;
}

.pricing-table .btn {
  white-space: nowrap;
  word-break: keep-all;
  padding: 0.65rem 1.35rem;
  min-width: 108px;
}

.pricing-table th {
  background-color: #f8fafc;
  font-weight: 600;
  color: var(--text-main);
}

.pricing-table tr:last-child td {
  border-bottom: none;
}

.pricing-table tr:hover td {
  background-color: #f8fafc;
}

.plan-name {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text-main);
}

.plan-price {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--primary);
}

.plan-price small {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-muted);
}

.badge-hot {
  display: inline-block;
  background-color: #ef4444;
  color: #ffffff;
  font-size: 0.75rem;
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  font-weight: 600;
  margin-left: 0.5rem;
}

/* 用户评价 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.review-stars {
  color: #f59e0b;
  margin-bottom: 0.5rem;
  font-size: 1rem;
}

.review-text {
  font-size: 0.925rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 1rem;
}

.review-user {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.user-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.95rem;
}

.user-meta strong {
  display: block;
  font-size: 0.9rem;
  color: var(--text-main);
}

.user-meta span {
  font-size: 0.8rem;
  color: var(--text-light);
}

/* FAQ 常见问题解答 (原生 details / summary, 默认 open) */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 850px;
  margin: 0 auto;
}

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

.faq-summary {
  padding: 1.25rem 1.5rem;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-main);
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
  transition: background-color 0.15s ease;
}

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

.faq-summary::after {
  content: "▾";
  font-size: 1.25rem;
  color: var(--primary);
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-summary::after {
  transform: rotate(180deg);
}

.faq-summary:hover {
  background-color: #f8fafc;
}

.faq-summary:focus-visible {
  outline: 2px solid var(--border-focus);
}

.faq-content {
  padding: 1rem 1.5rem 1.25rem;
  border-top: 1px solid var(--border-color);
  background-color: #ffffff;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

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

/* 知识科普与文章页面专属样式 */
.article-header {
  padding: 3rem 0 2rem;
  text-align: center;
  background: #f1f5f9;
  border-bottom: 1px solid var(--border-color);
}

.breadcrumbs {
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: 1rem;
}

.breadcrumbs a {
  color: var(--text-muted);
  text-decoration: none;
}

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

.article-container {
  max-width: 860px;
  margin: 0 auto;
  padding: 3rem 1.5rem 4rem;
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.8;
  color: #334155;
}

.article-content h2 {
  font-size: 1.6rem;
  text-align: left;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid #e2e8f0;
}

.article-content h3 {
  font-size: 1.3rem;
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
  color: #1e293b;
}

.article-content ul, .article-content ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}

.article-content li {
  margin-bottom: 0.5rem;
}

.article-cta-box {
  margin: 3rem 0;
  padding: 2rem;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border: 1px solid #bfdbfe;
  border-radius: var(--radius-lg);
  text-align: center;
}

.article-cta-box h3 {
  color: var(--primary-dark);
  margin-bottom: 0.5rem;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
  margin: 2.5rem 0;
}

.article-preview-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.article-preview-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.article-preview-card h3 {
  font-size: 1.15rem;
  line-height: 1.4;
  margin-bottom: 0.75rem;
}

.article-preview-card h3 a {
  color: var(--text-main);
  text-decoration: none;
}

.article-preview-card h3 a:hover {
  color: var(--primary);
}

/* 页脚 (严格只保留四个链接打开新页面) */
.site-footer {
  margin-top: auto;
  background-color: #0f172a;
  color: #94a3b8;
  padding: 3rem 0 2rem;
  border-top: 1px solid #1e293b;
}

.footer-nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 2.5rem;
  margin-bottom: 1.75rem;
  flex-wrap: wrap;
}

.footer-nav a {
  color: #cbd5e1;
  font-size: 0.95rem;
  font-weight: 500;
  text-decoration: none;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  transition: color 0.15s ease;
}

.footer-nav a:hover {
  color: #38bdf8;
  text-decoration: underline;
}

.footer-copy {
  text-align: center;
  font-size: 0.85rem;
  color: #64748b;
  border-top: 1px solid #1e293b;
  padding-top: 1.5rem;
}

/* ==========================================================================
   响应式媒体查询 (@media) 适配
   ========================================================================== */

/* 平板与窄屏 (<= 1024px) */
@media (max-width: 1024px) {
  .features-grid, .reviews-grid, .articles-grid, .pricing-cards-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* 手机端 (<= 768px) */
@media (max-width: 768px) {
  h1 { font-size: 1.85rem; }
  h2 { font-size: 1.5rem; }
  
  .hero-title { font-size: 2rem; }
  .hero-subtitle { font-size: 1.1rem; }
  
  .main-nav {
    gap: 0.75rem;
  }
  
  .features-grid, .reviews-grid, .articles-grid, .support-grid, .pricing-cards-grid {
    grid-template-columns: 1fr;
  }
  
  .pricing-card.featured-plan {
    transform: none;
  }
  
  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }
  
  .sea-shore-wrapper {
    height: 120px;
  }

  .beach-sand-layer {
    height: 50px;
  }

  .btn {
    width: 100%;
  }

  .pricing-table .btn {
    width: auto;
    white-space: nowrap;
  }

  .footer-nav {
    gap: 1.25rem;
    flex-direction: column;
  }
}

/* 超窄屏手机 (<= 390px) */
@media (max-width: 390px) {
  .container {
    padding-left: 1rem;
    padding-right: 1rem;
  }
  
  .hero-title {
    font-size: 1.75rem;
  }
}

/* 动效适配 */
@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;
  }
}