/* ==========================================================================
   隐云 (YinYun - yinyun.click) 官方落地页全套视觉与响应式设计系统
   ========================================================================== */

:root {
  --bg-dark: #070913;
  --bg-card: rgba(15, 20, 36, 0.75);
  --bg-card-hover: rgba(22, 30, 54, 0.9);
  --bg-card-featured: rgba(20, 26, 52, 0.85);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(0, 242, 254, 0.4);
  --border-featured: rgba(157, 78, 221, 0.5);

  --primary: #00f2fe;
  --primary-glow: rgba(0, 242, 254, 0.35);
  --secondary: #4facfe;
  --accent-purple: #9d4edd;
  --accent-purple-glow: rgba(157, 78, 221, 0.4);
  --accent-green: #10b981;
  --accent-orange: #f59e0b;

  --text-primary: #ffffff;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-dark);
  color: var(--text-primary);
  line-height: 1.65;
  overflow-x: hidden;
  position: relative;
  min-height: 100vh;
}

/* 动态背景画布 */
#yinyunCanvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  pointer-events: none;
}

/* 容器规范 */
.container {
  width: 100%;
  max-width: 1240px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
  position: relative;
  z-index: 1;
}

/* 顶部导航条 */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(7, 9, 19, 0.8);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  transition: var(--transition);
}

.site-header.scrolled {
  background: rgba(7, 9, 19, 0.95);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

/* 左侧 Logo 区域 */
.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-primary);
  transition: var(--transition);
}

.brand-logo:hover {
  opacity: 0.92;
  transform: translateY(-1px);
}

.brand-logo-img {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  object-fit: cover;
  box-shadow: 0 0 15px var(--primary-glow);
  border: 1px solid rgba(0, 242, 254, 0.3);
}

.brand-text-wrap {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-size: 1.3rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, #ffffff 30%, #00f2fe 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.brand-sub {
  font-size: 0.7rem;
  color: var(--primary);
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

/* 导航链接 */
.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  transition: var(--transition);
  position: relative;
  padding: 6px 0;
}

.nav-link:hover {
  color: #ffffff;
}

.nav-link:hover::after {
  width: 100%;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent-purple));
  transition: var(--transition);
}

/* 导航右侧按钮 */
.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* 移动端汉堡按钮 */
.mobile-toggle {
  display: none;
  background: transparent;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: 8px;
  border-radius: var(--radius-sm);
}

/* 移动端侧边抽屉 */
.mobile-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(6px);
  z-index: 198;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
}

.mobile-backdrop.open {
  opacity: 1;
  visibility: visible;
}

.mobile-drawer {
  position: fixed;
  top: 0;
  right: -320px;
  width: 300px;
  height: 100vh;
  background: #0b0f1f;
  border-left: 1px solid var(--border-color);
  z-index: 199;
  padding: 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: right 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  overflow-y: auto;
}

.mobile-drawer.open {
  right: 0;
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 28px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-color);
}

.drawer-close {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 4px;
}

.drawer-links {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.drawer-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 1.05rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.drawer-link:hover {
  color: var(--primary);
  background: rgba(0, 242, 254, 0.08);
}

/* 通用按钮系统 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-sm {
  padding: 7px 16px;
  font-size: 0.85rem;
  border-radius: var(--radius-sm);
}

.btn-lg {
  padding: 14px 32px;
  font-size: 1.1rem;
  border-radius: var(--radius-md);
}

.btn-primary {
  background: linear-gradient(135deg, #00f2fe 0%, #4facfe 100%);
  color: #070a14;
  box-shadow: 0 4px 18px rgba(0, 242, 254, 0.35);
}

.btn-primary:hover {
  box-shadow: 0 6px 24px rgba(0, 242, 254, 0.55);
  transform: translateY(-2px);
  filter: brightness(1.05);
}

.btn-outline {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-primary);
  border-color: var(--border-color);
  backdrop-filter: blur(8px);
}

.btn-outline:hover {
  background: rgba(0, 242, 254, 0.1);
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
}

.btn-purple {
  background: linear-gradient(135deg, #9d4edd 0%, #7928ca 100%);
  color: #ffffff;
  box-shadow: 0 4px 18px var(--accent-purple-glow);
}

.btn-purple:hover {
  box-shadow: 0 6px 24px rgba(157, 78, 221, 0.65);
  transform: translateY(-2px);
}

/* 首屏 Hero Section */
.hero-section {
  padding-top: 150px;
  padding-bottom: 90px;
  position: relative;
  z-index: 1;
}

/* 隐云专属背景光晕与装饰云 */
.hero-cloud-decor {
  position: absolute;
  top: 48%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: min(880px, 95vw);
  height: 440px;
  pointer-events: none;
  z-index: -1;
  opacity: 0.5;
}

.hero-cloud-svg {
  width: 100%;
  height: 100%;
  overflow: visible;
  animation: cloudPulse 8s ease-in-out infinite alternate;
}

@keyframes cloudPulse {
  0% { transform: scale(0.96) translateY(0); filter: drop-shadow(0 0 35px rgba(0, 242, 254, 0.25)); }
  100% { transform: scale(1.04) translateY(-8px); filter: drop-shadow(0 0 55px rgba(157, 78, 221, 0.35)); }
}

.hero-content {
  text-align: center;
  max-width: 920px;
  margin: 0 auto;
  position: relative;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 18px;
  border-radius: var(--radius-full);
  background: rgba(0, 242, 254, 0.08);
  border: 1px solid rgba(0, 242, 254, 0.25);
  color: var(--primary);
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 24px;
  animation: floatSlow 4s ease-in-out infinite;
}

.hero-pill-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--primary);
  box-shadow: 0 0 10px var(--primary);
}

.hero-title {
  font-size: clamp(2.2rem, 5vw, 3.8rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 24px;
  letter-spacing: -0.03em;
}

.text-gradient {
  background: linear-gradient(135deg, #ffffff 20%, #00f2fe 70%, #9d4edd 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: clamp(1rem, 2vw, 1.22rem);
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 36px;
  max-width: 780px;
  margin-left: auto;
  margin-right: auto;
}

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

.hero-guarantees {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 28px;
  flex-wrap: wrap;
  margin-bottom: 56px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.guarantee-item {
  display: flex;
  align-items: center;
  gap: 8px;
}

.guarantee-item svg {
  color: var(--primary);
}

/* 关键数据条 */
.hero-stats-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  background: rgba(15, 20, 36, 0.6);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
  backdrop-filter: blur(12px);
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.stat-num {
  font-size: 2rem;
  font-weight: 800;
  background: linear-gradient(135deg, #ffffff, var(--primary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1.1;
  margin-bottom: 6px;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* 板块通用头部 */
.section-header {
  text-align: center;
  max-width: 780px;
  margin: 0 auto 54px;
}

.section-tag {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  color: var(--primary);
  text-transform: uppercase;
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* 核心优势卡片网格 */
.features-section {
  padding: 80px 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  backdrop-filter: blur(12px);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--primary), transparent);
  opacity: 0;
  transition: var(--transition);
}

.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-4px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4);
}

.feature-card:hover::before {
  opacity: 1;
}

.feature-icon-box {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: rgba(0, 242, 254, 0.1);
  border: 1px solid rgba(0, 242, 254, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  margin-bottom: 20px;
}

.feature-title {
  font-size: 1.22rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: #ffffff;
}

.feature-desc {
  font-size: 0.94rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.feature-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 16px;
  color: var(--primary);
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: none;
  transition: var(--transition);
}

.feature-link:hover {
  color: #ffffff;
  transform: translateX(4px);
}

.feature-link svg {
  transition: transform 0.2s ease;
}

.feature-link:hover svg {
  transform: translateX(3px);
}

/* ==========================================================================
   价格方案区 (所有价格同排 Side-by-Side 重点实现)
   ========================================================================== */
.pricing-section {
  padding: 90px 0;
  background: linear-gradient(180deg, transparent 0%, rgba(13, 17, 36, 0.4) 50%, transparent 100%);
}

.pricing-row {
  display: grid;
  grid-template-columns: repeat(3, 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 30px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  backdrop-filter: blur(14px);
  position: relative;
  transition: var(--transition);
}

.pricing-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-5px);
  box-shadow: 0 16px 36px rgba(0, 0, 0, 0.4);
}

/* 高光爆款方案 (VIP2) */
.pricing-card.featured {
  background: var(--bg-card-featured);
  border: 2px solid var(--accent-purple);
  box-shadow: 0 8px 32px var(--accent-purple-glow);
  transform: scale(1.02);
}

.pricing-card.featured:hover {
  transform: scale(1.02) translateY(-5px);
  border-color: #c084fc;
  box-shadow: 0 16px 48px rgba(157, 78, 221, 0.55);
}

.pricing-badge-popular {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, #9d4edd, #00f2fe);
  color: #080914;
  font-size: 0.78rem;
  font-weight: 800;
  padding: 4px 16px;
  border-radius: var(--radius-full);
  letter-spacing: 0.05em;
  box-shadow: 0 4px 12px rgba(157, 78, 221, 0.5);
  white-space: nowrap;
}

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

.plan-name {
  font-size: 1.45rem;
  font-weight: 800;
  margin-bottom: 6px;
  color: #ffffff;
}

.plan-sub {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.5;
  min-height: 42px;
}

.plan-price-wrap {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-bottom: 16px;
}

.plan-currency {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--primary);
}

.plan-amount {
  font-size: 3rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: #ffffff;
  line-height: 1;
}

.plan-cycle {
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.plan-traffic-chip {
  display: inline-block;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  background: rgba(0, 242, 254, 0.1);
  border: 1px solid rgba(0, 242, 254, 0.25);
  color: var(--primary);
  font-size: 0.88rem;
  font-weight: 700;
  margin-bottom: 24px;
}

.plan-features-list {
  list-style: none;
  margin-bottom: 32px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.plan-feature-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.plan-feature-item svg {
  flex-shrink: 0;
  margin-top: 3px;
  color: var(--accent-green);
}

.plan-feature-item strong {
  color: #ffffff;
}

.plan-btn {
  width: 100%;
}

.pricing-notice {
  margin-top: 32px;
  text-align: center;
  font-size: 0.88rem;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.02);
  border: 1px dashed var(--border-color);
  padding: 14px 20px;
  border-radius: var(--radius-md);
}

/* ==========================================================================
   深度评测与推荐文章区 (Articles Section)
   ========================================================================== */
.articles-section {
  padding: 90px 0;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  backdrop-filter: blur(12px);
  transition: var(--transition);
}

.article-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-4px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4);
}

.article-tag-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.article-category {
  font-size: 0.78rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  background: rgba(0, 242, 254, 0.1);
  color: var(--primary);
  border: 1px solid rgba(0, 242, 254, 0.2);
}

.article-read-time {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.article-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.45;
  margin-bottom: 12px;
}

.article-card-title a {
  color: #ffffff;
  text-decoration: none;
  transition: var(--transition);
}

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

.article-card-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 20px;
}

.article-card-footer {
  border-top: 1px solid var(--border-color);
  padding-top: 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.article-read-btn {
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
  transition: var(--transition);
}

.article-read-btn:hover {
  color: #ffffff;
  transform: translateX(3px);
}

/* ==========================================================================
   真实用户评价 (User Reviews)
   ========================================================================== */
.reviews-section {
  padding: 90px 0;
  background: linear-gradient(180deg, transparent 0%, rgba(13, 17, 36, 0.4) 50%, transparent 100%);
}

.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: 28px 24px;
  backdrop-filter: blur(12px);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.review-card:hover {
  border-color: rgba(255, 255, 255, 0.18);
  transform: translateY(-3px);
}

.review-stars {
  color: #fbbf24;
  font-size: 0.95rem;
  margin-bottom: 14px;
}

.review-text {
  font-size: 0.94rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
  font-style: italic;
}

.review-user-info {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid var(--border-color);
  padding-top: 16px;
}

.review-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent-purple));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: #070913;
  font-size: 1rem;
}

.review-user-meta {
  display: flex;
  flex-direction: column;
}

.review-name {
  font-size: 0.95rem;
  font-weight: 700;
  color: #ffffff;
}

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

/* ==========================================================================
   常见问题与答疑 (FAQ Section)
   ========================================================================== */
.faq-section {
  padding: 90px 0;
}

.faq-container {
  max-width: 860px;
  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;
  backdrop-filter: blur(12px);
  transition: var(--transition);
}

.faq-item:hover {
  border-color: var(--border-hover);
}

.faq-question {
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  padding: 22px 24px;
  color: #ffffff;
  font-size: 1.05rem;
  font-weight: 700;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.faq-icon {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.06);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: transform 0.25s ease;
  color: var(--primary);
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
  background: var(--primary);
  color: #070913;
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
  padding: 0 24px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.75;
}

.faq-item.active .faq-answer {
  max-height: 600px;
  padding-bottom: 22px;
  transition: max-height 0.3s cubic-bezier(1, 0, 1, 0);
}

/* ==========================================================================
   外链推荐与行业工具 (External Links Section)
   ========================================================================== */
.extlinks-section {
  padding: 70px 0;
  border-top: 1px solid var(--border-color);
}

.extlinks-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.extlink-card {
  background: rgba(15, 20, 36, 0.5);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 14px;
  transition: var(--transition);
}

.extlink-card:hover {
  background: rgba(22, 30, 54, 0.8);
  border-color: var(--primary);
  transform: translateY(-2px);
}

.extlink-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background: rgba(0, 242, 254, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  font-size: 1.2rem;
  flex-shrink: 0;
}

.extlink-info {
  display: flex;
  flex-direction: column;
}

.extlink-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: #ffffff;
  display: flex;
  align-items: center;
  gap: 4px;
}

.extlink-desc {
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* ==========================================================================
   底部页脚 (Site Footer)
   ========================================================================== */
.site-footer {
  background: #05070d;
  border-top: 1px solid var(--border-color);
  padding: 60px 0 30px;
  position: relative;
  z-index: 1;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-top: 14px;
  max-width: 380px;
}

.footer-col-title {
  font-size: 0.98rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 18px;
}

.footer-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-list a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.88rem;
  transition: var(--transition);
}

.footer-list a:hover {
  color: var(--primary);
  transform: translateX(2px);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  color: var(--text-muted);
  flex-wrap: wrap;
  gap: 12px;
}

/* ==========================================================================
   文章详情页排版规范 (Article Single Page Layout)
   ========================================================================== */
.article-header {
  padding-top: 130px;
  padding-bottom: 40px;
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.breadcrumb a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: var(--transition);
}

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

.article-main-title {
  font-size: clamp(1.8rem, 4vw, 2.7rem);
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 18px;
}

.article-meta-bar {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: 0.88rem;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 24px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.85;
  color: #cbd5e1;
}

.article-content h2 {
  font-size: 1.65rem;
  font-weight: 800;
  color: #ffffff;
  margin-top: 48px;
  margin-bottom: 18px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.article-content h3 {
  font-size: 1.3rem;
  font-weight: 700;
  color: #f1f5f9;
  margin-top: 32px;
  margin-bottom: 14px;
}

.article-content p {
  margin-bottom: 22px;
}

.article-content ul, .article-content ol {
  margin-bottom: 24px;
  padding-left: 24px;
}

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

.article-content blockquote {
  background: rgba(0, 242, 254, 0.06);
  border-left: 4px solid var(--primary);
  padding: 16px 20px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 28px 0;
  color: #e2e8f0;
  font-style: normal;
}

.article-content a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: var(--transition);
}

.article-content a:hover {
  color: #ffffff;
}

.article-cta-box {
  background: linear-gradient(135deg, rgba(15, 20, 36, 0.9), rgba(30, 41, 74, 0.9));
  border: 2px solid var(--primary);
  border-radius: var(--radius-lg);
  padding: 36px 30px;
  text-align: center;
  margin: 50px 0;
  box-shadow: 0 10px 30px var(--primary-glow);
}

.article-cta-box h3 {
  font-size: 1.5rem;
  color: #ffffff;
  margin-bottom: 12px;
}

.article-cta-box p {
  color: var(--text-secondary);
  margin-bottom: 24px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* 相关文章推荐列表 */
.related-articles-section {
  margin-top: 60px;
  padding-top: 40px;
  border-top: 1px solid var(--border-color);
}

/* ==========================================================================
   移动端与响应式适配 (Media Queries)
   ========================================================================== */
@media (max-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-row {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin: 0 auto;
  }
  .pricing-card.featured {
    transform: none;
  }
  .pricing-card.featured:hover {
    transform: translateY(-5px);
  }
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .extlinks-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-top {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
  .hero-stats-bar {
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
  }
}

@media (max-width: 768px) {
  .nav-links, .nav-actions .btn-login {
    display: none;
  }
  .mobile-toggle {
    display: block;
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .articles-grid {
    grid-template-columns: 1fr;
  }
  .reviews-grid {
    grid-template-columns: 1fr;
  }
  .extlinks-grid {
    grid-template-columns: 1fr;
  }
  .footer-top {
    grid-template-columns: 1fr;
  }
  .hero-stats-bar {
    grid-template-columns: 1fr 1fr;
  }
  .hero-actions .btn {
    width: 100%;
  }
}

@media (max-width: 480px) {
  .hero-stats-bar {
    grid-template-columns: 1fr;
  }
  .hero-guarantees {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
}

/* 动画特效 */
@keyframes floatSlow {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-6px); }
}

.btn-shine {
  position: relative;
  overflow: hidden;
}

.btn-shine::after {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(
    60deg,
    rgba(255, 255, 255, 0) 20%,
    rgba(255, 255, 255, 0.3) 50%,
    rgba(255, 255, 255, 0) 80%
  );
  transform: rotate(30deg);
  animation: shineSweep 4s infinite ease-in-out;
}

@keyframes shineSweep {
  0% { transform: translateX(-100%) rotate(30deg); }
  30%, 100% { transform: translateX(100%) rotate(30deg); }
}

/* 返回顶部悬浮按钮 */
.back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: rgba(15, 23, 42, 0.85);
  border: 1px solid rgba(0, 242, 254, 0.35);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(10px);
  cursor: pointer;
  z-index: 99;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  text-decoration: none;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--primary);
  color: #070913;
  border-color: var(--primary);
  box-shadow: 0 6px 25px var(--primary-glow);
  transform: translateY(-3px);
}