/* ==========================================================================
   贝贝云 (Beibeiyun) - Playful Geometric 设计系统纯原生样式表
   零重型外部框架依赖 | 100% 原生 CSS | 极速秒开 | 无障碍合规
   ========================================================================== */

/* --------------------------------------------------------------------------
   设计系统权威 Token 声明 (Playful Geometric Design System)
   -------------------------------------------------------------------------- */
:root {
  --dp-color-ground: #fffdf5;
  --dp-color-panel: #ffffff;
  --dp-color-ink: #253044;
  --dp-color-outline: #252b3a;
  --dp-color-accent: #6434df;
  --dp-color-accent-secondary: #ff78c5;
  --dp-color-accent-warm: #ffd05b;
  --dp-color-accent-fresh: #9bf1cd;
  --dp-color-field-soft: #e9fff5;
  --dp-color-selection: #f1ebff;
  --dp-color-rule-muted: #b8b6c5;

  --dp-typography-display: "Host Grotesk", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --dp-typography-reading: "Instrument Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  
  --dp-typography-reading-compact: 16px;
  --dp-typography-label: 14px;
  --dp-typography-metadata: 13px;
  --dp-typography-reading-leading: 1.65;
  
  --dp-spacing-gap-compact: 12px;
  --dp-radius-corner: 17px;
  --dp-border-outline-width: 3px;
  --dp-border-detail-width: 2px;
  --dp-motion-interaction: 180ms;

  --dp-shadow-hard: 4px 4px 0px var(--dp-color-outline);
  --dp-shadow-hard-large: 6px 6px 0px var(--dp-color-outline);
  --dp-shadow-hard-small: 3px 3px 0px var(--dp-color-outline);
  --dp-shadow-violet: 4px 4px 0px var(--dp-color-accent);
}

/* --------------------------------------------------------------------------
   基础重置与无障碍保障
   -------------------------------------------------------------------------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  background-color: var(--dp-color-ground);
  color: var(--dp-color-ink);
}

body {
  font-family: var(--dp-typography-reading);
  font-size: var(--dp-typography-reading-compact);
  line-height: var(--dp-typography-reading-leading);
  background-color: var(--dp-color-ground);
  color: var(--dp-color-ink);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
}

/* 键盘焦点指示器 */
:focus-visible {
  outline: 3px solid var(--dp-color-accent);
  outline-offset: 3px;
}

/* 跳过内容链接（无障碍支持） */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  background: var(--dp-color-accent-warm);
  color: var(--dp-color-outline);
  padding: 0.75rem 1.25rem;
  font-weight: 700;
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  box-shadow: var(--dp-shadow-hard);
  z-index: 9999;
  text-decoration: none;
  transition: top var(--dp-motion-interaction) ease;
}

.skip-link:focus {
  top: 1rem;
}

/* 锚点滚动留白 */
[id] {
  scroll-margin-top: 100px;
}

/* 容器通用布局 */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* --------------------------------------------------------------------------
   页眉与导航 (Header & Navigation)
   -------------------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: var(--dp-color-ground);
  border-bottom: var(--dp-border-outline-width) solid var(--dp-color-outline);
  padding: 0.85rem 0;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.brand-logo {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  font-family: var(--dp-typography-display);
  font-size: 1.4rem;
  font-weight: 900;
  color: var(--dp-color-ink);
}

.logo-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  background-color: var(--dp-color-accent);
  color: #ffffff;
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  border-radius: 10px;
  box-shadow: 2px 2px 0px var(--dp-color-outline);
  font-size: 1.1rem;
  font-weight: 900;
}

.logo-tag {
  font-size: 0.75rem;
  background-color: var(--dp-color-accent-warm);
  color: var(--dp-color-ink);
  padding: 0.15rem 0.5rem;
  border-radius: 8px;
  border: 1.5px solid var(--dp-color-outline);
  font-weight: 700;
  margin-left: 0.3rem;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  list-style: none;
}

.nav-link {
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--dp-color-ink);
  padding: 0.4rem 0.6rem;
  border-radius: 8px;
  transition: all var(--dp-motion-interaction) ease;
}

.nav-link:hover {
  background-color: var(--dp-color-selection);
  color: var(--dp-color-accent);
}

.nav-badge-link {
  background-color: var(--dp-color-accent-fresh);
  color: var(--dp-color-ink);
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  box-shadow: 2px 2px 0px var(--dp-color-outline);
}

.nav-badge-link:hover {
  background-color: var(--dp-color-accent-warm);
  transform: translate(-1px, -1px);
  box-shadow: 3px 3px 0px var(--dp-color-outline);
}

/* 按钮基础类 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  min-width: 48px;
  padding: 0.65rem 1.5rem;
  font-family: var(--dp-typography-reading);
  font-size: 1rem;
  font-weight: 800;
  text-decoration: none;
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  box-shadow: var(--dp-shadow-hard);
  cursor: pointer;
  transition: transform var(--dp-motion-interaction) ease, box-shadow var(--dp-motion-interaction) ease;
  line-height: 1.2;
}

.btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--dp-shadow-hard-large);
}

.btn:active {
  transform: translate(2px, 2px);
  box-shadow: 2px 2px 0px var(--dp-color-outline);
}

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

.btn-secondary {
  background-color: var(--dp-color-panel);
  color: var(--dp-color-ink);
}

.btn-warm {
  background-color: var(--dp-color-accent-warm);
  color: var(--dp-color-ink);
}

.btn-mint {
  background-color: var(--dp-color-accent-fresh);
  color: var(--dp-color-ink);
}

.btn-sm {
  min-height: 40px;
  padding: 0.45rem 1.1rem;
  font-size: 0.9rem;
}

/* --------------------------------------------------------------------------
   主视觉区 (Hero Section)
   -------------------------------------------------------------------------- */
.hero-section {
  padding: 3.5rem 0 2.5rem;
  position: relative;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.25fr 0.95fr;
  gap: 3rem;
  align-items: center;
}

.hero-tag-strip {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background-color: var(--dp-color-selection);
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  border-radius: 30px;
  padding: 0.35rem 0.9rem;
  margin-bottom: 1.25rem;
  box-shadow: var(--dp-shadow-hard-small);
}

.hero-tag-dot {
  width: 10px;
  height: 10px;
  background-color: var(--dp-color-accent);
  border-radius: 50%;
  display: inline-block;
}

.hero-tag-text {
  font-size: var(--dp-typography-metadata);
  font-weight: 800;
  color: var(--dp-color-accent);
  letter-spacing: 0.04em;
}

.hero-headline {
  font-family: var(--dp-typography-display);
  font-size: clamp(2.5rem, 5vw, 3.8rem);
  font-weight: 900;
  line-height: 1.15;
  color: var(--dp-color-ink);
  letter-spacing: -0.02em;
  margin-bottom: 1.2rem;
}

.hero-headline .text-violet {
  color: var(--dp-color-accent);
  display: inline-block;
  position: relative;
}

.hero-headline .text-violet::after {
  content: "";
  position: absolute;
  bottom: 4px;
  left: 0;
  width: 100%;
  height: 10px;
  background-color: var(--dp-color-accent-fresh);
  z-index: -1;
  border-radius: 4px;
}

.hero-subtitle {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--dp-color-accent);
  margin-bottom: 1rem;
}

.hero-intro {
  font-size: 1.05rem;
  color: var(--dp-color-ink);
  margin-bottom: 2rem;
  max-width: 580px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 2.5rem;
}

/* 事实条带 (Fact Strip) */
.fact-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}

.fact-item {
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  padding: 0.9rem 1rem;
  box-shadow: var(--dp-shadow-hard-small);
  text-align: center;
}

.fact-item:nth-child(1) { background-color: var(--dp-color-field-soft); }
.fact-item:nth-child(2) { background-color: #fff9e6; }
.fact-item:nth-child(3) { background-color: var(--dp-color-selection); }

.fact-value {
  font-family: var(--dp-typography-display);
  font-size: 1.45rem;
  font-weight: 900;
  color: var(--dp-color-ink);
  display: block;
}

.fact-label {
  font-size: 0.8rem;
  font-weight: 700;
  color: #556075;
}

/* 几何拼搭画板 (Geometric Assembly Canvas) */
.hero-assembly {
  position: relative;
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: 24px;
  padding: 2rem;
  box-shadow: var(--dp-shadow-hard-large);
}

.assembly-book-card {
  background: var(--dp-color-ground);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  padding: 1.5rem;
  box-shadow: var(--dp-shadow-hard);
  margin-bottom: 1.25rem;
  position: relative;
}

.assembly-badge-top {
  position: absolute;
  top: -14px;
  right: 20px;
  background-color: var(--dp-color-accent-warm);
  color: var(--dp-color-ink);
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.2rem 0.65rem;
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  border-radius: 12px;
  box-shadow: 2px 2px 0px var(--dp-color-outline);
}

.speed-meter-mock {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: var(--dp-border-detail-width) dashed var(--dp-color-rule-muted);
}

.speed-tag {
  background-color: var(--dp-color-accent-fresh);
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  border-radius: 8px;
  padding: 0.25rem 0.6rem;
  font-size: 0.8rem;
  font-weight: 800;
}

/* 几何拼搭装饰物 */
.geom-float-1 {
  position: absolute;
  top: -20px;
  left: -20px;
  width: 50px;
  height: 50px;
  background: var(--dp-color-accent-secondary);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: 50%;
  box-shadow: var(--dp-shadow-hard-small);
  z-index: 10;
}

.geom-float-2 {
  position: absolute;
  bottom: -15px;
  right: -15px;
  width: 44px;
  height: 44px;
  background: var(--dp-color-accent-warm);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: 10px;
  transform: rotate(18deg);
  box-shadow: var(--dp-shadow-hard-small);
  z-index: 10;
}

/* --------------------------------------------------------------------------
   核心优势卡片 (Core Advantages - 3 Cards)
   -------------------------------------------------------------------------- */
.section-wrapper {
  padding: 4rem 0;
  border-top: var(--dp-border-outline-width) solid var(--dp-color-outline);
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 3rem;
}

.section-pill {
  display: inline-block;
  background-color: var(--dp-color-accent-fresh);
  color: var(--dp-color-ink);
  font-size: 0.8rem;
  font-weight: 800;
  padding: 0.3rem 0.85rem;
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  border-radius: 20px;
  box-shadow: var(--dp-shadow-hard-small);
  margin-bottom: 0.75rem;
}

.section-title {
  font-family: var(--dp-typography-display);
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 900;
  color: var(--dp-color-ink);
  line-height: 1.25;
  margin-bottom: 0.75rem;
}

.section-desc {
  font-size: 1.05rem;
  color: #4b5568;
}

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

.card-playful {
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  padding: 2rem 1.75rem;
  box-shadow: var(--dp-shadow-hard);
  display: flex;
  flex-direction: column;
  transition: transform var(--dp-motion-interaction) ease, box-shadow var(--dp-motion-interaction) ease;
}

.card-playful:hover {
  transform: translate(-3px, -3px);
  box-shadow: var(--dp-shadow-hard-large);
}

.card-icon-box {
  width: 64px;
  height: 64px;
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  margin-bottom: 1.5rem;
  box-shadow: var(--dp-shadow-hard-small);
}

.card-icon-box.icon-violet { background-color: var(--dp-color-selection); color: var(--dp-color-accent); }
.card-icon-box.icon-warm { background-color: #fff9e6; color: #b78103; }
.card-icon-box.icon-mint { background-color: var(--dp-color-field-soft); color: #0d7f54; }

.card-title {
  font-family: var(--dp-typography-display);
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--dp-color-ink);
  margin-bottom: 0.75rem;
}

.card-text {
  font-size: 0.95rem;
  color: #4a5568;
  line-height: 1.65;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.card-badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.mini-badge {
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.2rem 0.55rem;
  background-color: var(--dp-color-ground);
  border: 1.5px solid var(--dp-color-outline);
  border-radius: 8px;
}

/* --------------------------------------------------------------------------
   流媒体与 AI 支持图卡 (Streaming & AI Showcase)
   -------------------------------------------------------------------------- */
.showcase-book {
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: 24px;
  box-shadow: var(--dp-shadow-hard-large);
  padding: 2.5rem;
  position: relative;
}

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

.media-panel-title {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--dp-typography-display);
  font-size: 1.3rem;
  font-weight: 800;
  margin-bottom: 1.25rem;
  color: var(--dp-color-ink);
}

.media-icon-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background-color: var(--dp-color-accent-secondary);
  color: #ffffff;
  border-radius: 8px;
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  box-shadow: 2px 2px 0px var(--dp-color-outline);
  font-size: 0.9rem;
}

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

.service-card {
  background-color: var(--dp-color-ground);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  padding: 1rem;
  display: flex;
  align-items: center;
  gap: 0.85rem;
  box-shadow: var(--dp-shadow-hard-small);
}

.service-logo-box {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 900;
  font-size: 1.1rem;
  flex-shrink: 0;
}

.service-info h4 {
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--dp-color-ink);
  margin-bottom: 0.15rem;
}

.service-info p {
  font-size: 0.75rem;
  color: #556075;
}

/* --------------------------------------------------------------------------
   套餐价格对比表 (Pricing Tickets Table)
   -------------------------------------------------------------------------- */
.pricing-wrapper {
  background-color: var(--dp-color-field-soft);
  border-top: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-bottom: var(--dp-border-outline-width) solid var(--dp-color-outline);
}

.pricing-table-container {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: 24px;
  box-shadow: var(--dp-shadow-hard-large);
  margin-bottom: 2rem;
}

.pricing-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
}

.pricing-table caption {
  caption-side: top;
  font-family: var(--dp-typography-display);
  font-size: 1.1rem;
  font-weight: 800;
  padding: 1.25rem;
  background: var(--dp-color-selection);
  border-bottom: var(--dp-border-outline-width) solid var(--dp-color-outline);
  color: var(--dp-color-accent);
  text-align: left;
}

.pricing-table th,
.pricing-table td {
  padding: 1.2rem 1.25rem;
  border-bottom: var(--dp-border-detail-width) solid var(--dp-color-rule-muted);
  border-right: var(--dp-border-detail-width) solid var(--dp-color-rule-muted);
  vertical-align: middle;
}

.pricing-table th:last-child,
.pricing-table td:last-child {
  border-right: none;
}

.pricing-table thead th {
  background-color: #f7f9fd;
  font-family: var(--dp-typography-display);
  font-weight: 800;
  font-size: 1.1rem;
  color: var(--dp-color-ink);
}

.pricing-table thead th.plan-featured {
  background-color: var(--dp-color-selection);
  position: relative;
}

.badge-featured {
  position: absolute;
  top: 6px;
  right: 12px;
  background: var(--dp-color-accent);
  color: #ffffff;
  font-size: 0.7rem;
  font-weight: 800;
  padding: 0.2rem 0.5rem;
  border-radius: 8px;
  border: 1.5px solid var(--dp-color-outline);
}

.price-val {
  font-family: var(--dp-typography-display);
  font-size: 1.7rem;
  font-weight: 900;
  color: var(--dp-color-accent);
}

.price-period {
  font-size: 0.85rem;
  color: #64748b;
  font-weight: 600;
}

.pricing-table tbody tr:hover {
  background-color: #fcfdfe;
}

.check-icon {
  color: #10b981;
  font-weight: 900;
  font-size: 1.1rem;
  margin-right: 0.35rem;
}

/* --------------------------------------------------------------------------
   用户评价背书 (User Reviews & Testimonials)
   -------------------------------------------------------------------------- */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.review-bubble {
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  padding: 1.75rem;
  box-shadow: var(--dp-shadow-hard);
  position: relative;
  display: flex;
  flex-direction: column;
}

.review-stars {
  color: #f59e0b;
  font-size: 1.15rem;
  margin-bottom: 0.75rem;
}

.review-text {
  font-size: 0.95rem;
  color: var(--dp-color-ink);
  line-height: 1.6;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  border-top: var(--dp-border-detail-width) dashed var(--dp-color-rule-muted);
  padding-top: 1rem;
}

.author-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: #ffffff;
}

.author-info h4 {
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--dp-color-ink);
}

.author-info p {
  font-size: 0.75rem;
  color: #64748b;
}

/* --------------------------------------------------------------------------
   常见问题解答 (FAQ - Details/Summary 原生展开)
   -------------------------------------------------------------------------- */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 900px;
  margin: 0 auto;
}

.faq-item {
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  box-shadow: var(--dp-shadow-hard-small);
  overflow: hidden;
  transition: all var(--dp-motion-interaction) ease;
}

.faq-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 1.5rem;
  font-family: var(--dp-typography-display);
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--dp-color-ink);
  cursor: pointer;
  list-style: none;
  background-color: #ffffff;
  user-select: none;
}

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

.faq-summary:hover {
  background-color: var(--dp-color-selection);
}

.faq-icon-tag {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  background: var(--dp-color-accent-warm);
  border: var(--dp-border-detail-width) solid var(--dp-color-outline);
  border-radius: 8px;
  font-size: 1.1rem;
  font-weight: 900;
  transition: transform var(--dp-motion-interaction) ease;
}

details[open] .faq-icon-tag {
  transform: rotate(45deg);
  background: var(--dp-color-accent-fresh);
}

.faq-body {
  padding: 0 1.5rem 1.35rem 1.5rem;
  font-size: 0.95rem;
  color: #4a5568;
  line-height: 1.7;
  border-top: var(--dp-border-detail-width) dashed var(--dp-color-rule-muted);
  margin-top: -0.25rem;
  padding-top: 1rem;
  background-color: #fafbfc;
}

.faq-body a {
  color: var(--dp-color-accent);
  font-weight: 700;
  text-decoration: underline;
}

/* --------------------------------------------------------------------------
   收尾呼吁区 (Closing CTA Banner)
   -------------------------------------------------------------------------- */
.closing-cover {
  background-color: var(--dp-color-accent-fresh);
  border-top: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-bottom: var(--dp-border-outline-width) solid var(--dp-color-outline);
  padding: 4.5rem 0;
  position: relative;
}

.closing-card {
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: 24px;
  padding: 3rem 2rem;
  text-align: center;
  box-shadow: var(--dp-shadow-hard-large);
  max-width: 800px;
  margin: 0 auto;
  position: relative;
}

.closing-title {
  font-family: var(--dp-typography-display);
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 900;
  color: var(--dp-color-ink);
  margin-bottom: 1rem;
  line-height: 1.25;
}

.closing-desc {
  font-size: 1.1rem;
  color: #4a5568;
  margin-bottom: 2rem;
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   规范页脚 (Footer - 严格只保留四个标题，在新页面打开)
   -------------------------------------------------------------------------- */
.site-footer {
  background-color: var(--dp-color-outline);
  color: #f7f9fd;
  padding: 3.5rem 0 2rem;
  margin-top: auto;
}

.footer-nav-bar {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 2.5rem;
  flex-wrap: wrap;
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid #42495b;
}

.footer-title-link {
  font-family: var(--dp-typography-display);
  font-size: 1.1rem;
  font-weight: 800;
  color: #ffffff;
  text-decoration: none;
  padding: 0.5rem 1rem;
  border: var(--dp-border-detail-width) solid transparent;
  border-radius: var(--dp-radius-corner);
  transition: all var(--dp-motion-interaction) ease;
}

.footer-title-link:hover {
  background-color: var(--dp-color-accent);
  color: #ffffff;
  border-color: #ffffff;
  transform: translateY(-2px);
}

.footer-bottom-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: var(--dp-typography-metadata);
  color: #a0aec0;
}

/* --------------------------------------------------------------------------
   知识科普与文章页面专项样式 (Knowledge & Articles)
   -------------------------------------------------------------------------- */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: var(--dp-typography-label);
  font-weight: 700;
  margin-bottom: 1.75rem;
  flex-wrap: wrap;
}

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

.breadcrumbs span {
  color: #718096;
}

.article-hero-box {
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: 20px;
  padding: 2.5rem;
  box-shadow: var(--dp-shadow-hard);
  margin-bottom: 2.5rem;
}

.article-meta-row {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  font-size: var(--dp-typography-metadata);
  font-weight: 700;
  color: #64748b;
  margin-top: 1rem;
  flex-wrap: wrap;
}

.article-content {
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: 20px;
  padding: 2.5rem;
  box-shadow: var(--dp-shadow-hard);
  margin-bottom: 3rem;
  line-height: 1.85;
  font-size: 1.05rem;
}

.article-content h2 {
  font-family: var(--dp-typography-display);
  font-size: 1.5rem;
  font-weight: 900;
  color: var(--dp-color-ink);
  margin: 2rem 0 1rem;
  padding-bottom: 0.5rem;
  border-bottom: var(--dp-border-detail-width) dashed var(--dp-color-rule-muted);
}

.article-content h3 {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--dp-color-accent);
  margin: 1.5rem 0 0.75rem;
}

.article-content p {
  margin-bottom: 1.25rem;
  color: #2d3748;
}

.article-content ul, 
.article-content ol {
  margin: 1rem 0 1.5rem 1.75rem;
  color: #2d3748;
}

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

.article-content a {
  color: var(--dp-color-accent);
  font-weight: 700;
  text-decoration: underline;
}

.article-cta-box {
  background: var(--dp-color-field-soft);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  padding: 1.75rem;
  margin: 2rem 0;
  box-shadow: var(--dp-shadow-hard-small);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}

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

.article-card-item {
  background: var(--dp-color-panel);
  border: var(--dp-border-outline-width) solid var(--dp-color-outline);
  border-radius: var(--dp-radius-corner);
  padding: 1.75rem;
  box-shadow: var(--dp-shadow-hard);
  display: flex;
  flex-direction: column;
  transition: transform var(--dp-motion-interaction) ease, box-shadow var(--dp-motion-interaction) ease;
}

.article-card-item:hover {
  transform: translate(-3px, -3px);
  box-shadow: var(--dp-shadow-hard-large);
}

.article-card-item h3 {
  font-family: var(--dp-typography-display);
  font-size: 1.2rem;
  font-weight: 800;
  line-height: 1.4;
  margin-bottom: 0.75rem;
}

.article-card-item h3 a {
  color: var(--dp-color-ink);
  text-decoration: none;
}

.article-card-item h3 a:hover {
  color: var(--dp-color-accent);
}

.article-card-item p {
  font-size: 0.9rem;
  color: #4a5568;
  line-height: 1.6;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: var(--dp-border-detail-width) dashed var(--dp-color-rule-muted);
  padding-top: 0.85rem;
  font-size: var(--dp-typography-metadata);
  font-weight: 700;
  color: #718096;
}

/* --------------------------------------------------------------------------
   响应式媒体查询 (@media)
   -------------------------------------------------------------------------- */
@media (max-width: 1100px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  
  .advantages-grid,
  .reviews-grid,
  .articles-catalog-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .showcase-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .header-inner {
    flex-wrap: wrap;
  }

  .nav-menu {
    order: 3;
    width: 100%;
    justify-content: flex-start;
    overflow-x: auto;
    padding-top: 0.5rem;
    gap: 0.5rem;
  }

  .nav-link {
    font-size: 0.85rem;
    padding: 0.35rem 0.5rem;
    white-space: nowrap;
  }

  .advantages-grid,
  .reviews-grid,
  .articles-catalog-grid,
  .fact-strip,
  .media-tags-cloud {
    grid-template-columns: 1fr;
  }

  .hero-headline {
    font-size: 2.2rem;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

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

  .footer-nav-bar {
    gap: 1.25rem;
    flex-direction: column;
    text-align: center;
  }

  .footer-bottom-row {
    flex-direction: column;
    text-align: center;
    gap: 0.75rem;
  }
  
  .pricing-table th,
  .pricing-table td {
    padding: 0.85rem;
    font-size: 0.85rem;
  }

  .article-cta-box {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 390px) {
  .container {
    padding: 0 1rem;
  }

  .hero-headline {
    font-size: 1.85rem;
  }

  .btn {
    padding: 0.6rem 1rem;
    font-size: 0.95rem;
  }
}

/* 用户减少动态偏好 */
@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;
  }
  .btn:hover,
  .card-playful:hover,
  .article-card-item:hover {
    transform: none !important;
  }
}