@import url('https://fonts.googleapis.com/css2?family=Nunito+Sans:wght@300;400;500;600;700&family=Varela+Round&display=swap');

/* ===== 基础变量 ===== */
:root {
  --c-main: #c8e0f4;
  --c-accent: #f5e0e8;
  --c-ink: #171f26;
  --c-ink-soft: #3a4a58;
  --c-ink-mute: #6b7f8f;
  --c-main-dark: #a8c8e8;
  --c-main-light: #e4f0fa;
  --c-accent-dark: #e0c4d0;
  --c-accent-light: #fdf0f4;
  --c-surface: #d8eaf6;
  --c-white: #ffffff;
  --shadow-out: -4px -4px 12px rgba(255,255,255,0.85), 5px 5px 14px rgba(150,170,190,0.35);
  --shadow-in: inset 3px 3px 8px rgba(150,170,190,0.35), inset -3px -3px 8px rgba(255,255,255,0.8);
  --shadow-card: -3px -3px 8px rgba(255,255,255,0.9), 3px 3px 10px rgba(140,165,185,0.3);
  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --font-main: 'Nunito Sans', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-brand: 'Varela Round', 'Nunito Sans', sans-serif;
  --transition: 150ms ease;
  --nav-h: 64px;
}

/* ===== 重置 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
  font-family: var(--font-main);
  background: var(--c-main);
  color: var(--c-ink);
  line-height: 1.7;
  min-height: 100vh;
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; border-radius: var(--radius-sm); }
a { color: var(--c-ink); text-decoration: none; }
a:hover { color: var(--c-ink-soft); }
ol, ul { list-style: none; }
button { cursor: pointer; font-family: var(--font-main); }

/* ===== 公告条 ===== */
.announce-bar {
  background: linear-gradient(90deg, var(--c-accent-dark), var(--c-accent), var(--c-main-dark));
  color: var(--c-ink);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-align: center;
  padding: 8px 16px;
  position: sticky;
  top: 0;
  z-index: 100;
}

/* ===== 导航（底部固定条） ===== */
.site-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 200;
  background: linear-gradient(135deg, var(--c-main-light), var(--c-main));
  box-shadow: 0 -4px 20px rgba(150,170,190,0.3), 0 -1px 0 rgba(255,255,255,0.8);
  padding: 0 16px;
}

.nav-brand {
  display: none;
  text-align: center;
  padding: 10px 0 4px;
}
.nav-brand a {
  font-family: var(--font-brand);
  font-size: 1rem;
  font-weight: 700;
  color: var(--c-ink);
  letter-spacing: 0.04em;
}

.site-nav ol {
  display: flex;
  flex-wrap: nowrap;
  overflow-x: auto;
  gap: 4px;
  padding: 8px 0;
  scrollbar-width: none;
}
.site-nav ol::-webkit-scrollbar { display: none; }

.site-nav ol li a {
  display: flex;
  align-items: center;
  white-space: nowrap;
  padding: 10px 14px;
  min-height: 44px;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--c-ink-soft);
  border-radius: var(--radius-sm);
  background: linear-gradient(145deg, var(--c-main-light), var(--c-surface));
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition), transform var(--transition), background var(--transition);
}
.site-nav ol li a:hover,
.site-nav ol li a:active {
  box-shadow: var(--shadow-in);
  transform: scale(0.97);
  background: linear-gradient(145deg, var(--c-surface), var(--c-main-light));
}

/* ===== 底部固定导航占位 ===== */
.bottom-nav-spacer { height: calc(var(--nav-h) + 20px); }

/* ===== Hero（首页）===== */
.hero-section {
  min-height: 70vh;
  display: flex;
  align-items: center;
  gap: 0;
  position: relative;
  overflow: hidden;
  background: linear-gradient(145deg, var(--c-main-light), var(--c-main));
}

.hero-media {
  flex: 0 0 50%;
  height: 70vh;
  overflow: hidden;
  position: relative;
}
.hero-img,
.hero-placeholder {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 0;
}
.hero-placeholder {
  background: linear-gradient(135deg, var(--c-accent) 0%, var(--c-main-dark) 50%, var(--c-accent-light) 100%);
}

/* 斜切色带分割 */
.hero-media::after {
  content: '';
  position: absolute;
  top: 0;
  right: -1px;
  width: 80px;
  height: 100%;
  background: linear-gradient(145deg, var(--c-main-light), var(--c-main));
  clip-path: polygon(40% 0%, 100% 0%, 100% 100%, 0% 100%);
}

.hero-text {
  flex: 1 1 50%;
  padding: 48px 40px 48px 20px;
  text-align: right;
}
.hero-eyebrow {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--c-ink-mute);
  margin-bottom: 12px;
  text-transform: uppercase;
}
.hero-text h1 {
  font-family: var(--font-brand);
  font-size: clamp(1.6rem, 4vw, 2.6rem);
  font-weight: 700;
  line-height: 1.25;
  color: var(--c-ink);
  margin-bottom: 16px;
}
.hero-lead {
  font-size: 1rem;
  color: var(--c-ink-soft);
  margin-bottom: 28px;
  max-width: 360px;
  margin-left: auto;
}

/* ===== 按钮 ===== */
.btn-primary {
  display: inline-block;
  padding: 13px 28px;
  min-height: 44px;
  background: linear-gradient(145deg, var(--c-accent), var(--c-accent-dark));
  color: var(--c-ink);
  font-weight: 700;
  font-size: 0.95rem;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-out);
  transition: box-shadow var(--transition), transform var(--transition);
  border: none;
}
.btn-primary:hover { color: var(--c-ink); }
.btn-primary:active {
  box-shadow: var(--shadow-in);
  transform: scale(0.97);
}

.btn-secondary {
  display: inline-block;
  padding: 10px 20px;
  min-height: 40px;
  background: linear-gradient(145deg, var(--c-main-light), var(--c-surface));
  color: var(--c-ink-soft);
  font-weight: 600;
  font-size: 0.88rem;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition), transform var(--transition);
  margin: 4px 0;
  width: 100%;
  text-align: center;
}
.btn-secondary:hover { color: var(--c-ink); }
.btn-secondary:active {
  box-shadow: var(--shadow-in);
  transform: scale(0.97);
}

/* ===== 内容区（prose + sidebar）===== */
.content-section {
  padding: 48px 20px;
  background: linear-gradient(145deg, var(--c-main-light), var(--c-main));
}

.content-wrap {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  gap: 40px;
  align-items: flex-start;
}

.prose-area {
  flex: 1 1 0;
  min-width: 0;
  background: linear-gradient(145deg, var(--c-main-light), var(--c-surface));
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-out);
  padding: 36px 36px;
}

/* ===== 侧边栏 ===== */
.sidebar {
  flex: 0 0 260px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  background: linear-gradient(145deg, var(--c-accent-light), var(--c-accent));
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-out);
  padding: 28px 24px;
  position: sticky;
  top: 24px;
}
.sidebar h2 {
  font-family: var(--font-brand);
  font-size: 1.05rem;
  color: var(--c-ink);
  font-weight: 700;
}
.sidebar hr {
  border: none;
  border-top: 2px solid rgba(23,31,38,0.12);
  margin: 0;
}
.sidebar-nav li {
  padding: 2px 0;
}
.sidebar-nav li a {
  display: block;
  padding: 8px 12px;
  min-height: 40px;
  font-size: 0.88rem;
  color: var(--c-ink-soft);
  border-radius: var(--radius-sm);
  background: linear-gradient(145deg, rgba(255,255,255,0.6), rgba(200,224,244,0.3));
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition), transform var(--transition);
  line-height: 1.4;
  display: flex;
  align-items: center;
}
.sidebar-nav li a:hover {
  box-shadow: var(--shadow-in);
  transform: scale(0.98);
  color: var(--c-ink);
}
.sidebar-cta {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 8px;
}
.sidebar-notice {
  background: linear-gradient(145deg, var(--c-main-light), var(--c-main));
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  font-size: 0.82rem;
  color: var(--c-ink-soft);
  box-shadow: var(--shadow-in);
}

/* ===== prose 内部样式 ===== */
.prose-area h2,
.prose-area h3 {
  font-family: var(--font-brand);
  color: var(--c-ink);
  margin-top: 32px;
  margin-bottom: 8px;
}
.prose-area h2 { font-size: 1.35rem; }
.prose-area h3 { font-size: 1.1rem; }
.prose-area hr {
  border: none;
  border-top: 2px solid rgba(23,31,38,0.1);
  margin: 8px 0 20px;
}
.prose-area p { margin-bottom: 16px; color: var(--c-ink-soft); }
.prose-area ul, .prose-area ol {
  padding-left: 20px;
  margin-bottom: 16px;
  list-style: disc;
}
.prose-area ol { list-style: decimal; }
.prose-area li { margin-bottom: 6px; color: var(--c-ink-soft); }
.prose-area a {
  color: var(--c-ink);
  text-decoration: underline;
  text-underline-offset: 3px;
}
.prose-area strong { color: var(--c-ink); font-weight: 700; }

/* ===== 卡片网格 ===== */
.cards-section,
.related-section,
.other-features-section,
.faq-guides-section,
.about-links-section,
.privacy-extra-section {
  padding: 40px 20px;
  background: linear-gradient(145deg, var(--c-main), var(--c-surface));
}
.cards-section h2,
.related-section h2,
.other-features-section h2,
.faq-guides-section h2,
.about-links-section h2,
.privacy-extra-section h2 {
  font-family: var(--font-brand);
  font-size: 1.3rem;
  color: var(--c-ink);
  text-align: center;
  max-width: 1100px;
  margin: 0 auto 4px;
}
.cards-section hr,
.related-section hr,
.other-features-section hr,
.faq-guides-section hr,
.about-links-section hr,
.privacy-extra-section hr {
  border: none;
  border-top: 2px solid rgba(23,31,38,0.1);
  max-width: 1100px;
  margin: 0 auto 24px;
}

.cards-figure,
.about-figure {
  max-width: 1100px;
  margin: 0 auto;
}

.card-grid,
.about-quick-links {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
}

/* 子页卡片：描边无阴影 */
.child-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 22px 20px;
  background: linear-gradient(145deg, var(--c-main-light), var(--c-surface));
  border: 1.5px solid rgba(23,31,38,0.1);
  border-radius: var(--radius-sm);
  box-shadow: none;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
  color: var(--c-ink);
  text-decoration: none;
}
.child-card:hover {
  border-color: var(--c-main-dark);
  box-shadow: var(--shadow-card);
  transform: translateY(-2px);
  color: var(--c-ink);
}
.child-card:active {
  transform: scale(0.97);
  box-shadow: var(--shadow-in);
}
.child-card strong {
  font-family: var(--font-brand);
  font-size: 1rem;
  font-weight: 700;
  color: var(--c-ink);
  line-height: 1.3;
}
.child-card span {
  font-size: 0.84rem;
  color: var(--c-ink-mute);
  line-height: 1.5;
}

/* ===== Hero（内页）===== */
.page-hero-section,
.about-hero-section,
.privacy-hero-section,
.faq-hero,
.feature-hero-section {
  padding: 52px 20px 40px;
  background: linear-gradient(145deg, var(--c-accent-light), var(--c-accent), var(--c-main));
  position: relative;
  overflow: hidden;
}
.page-hero-inner,
.about-hero-inner {
  max-width: 780px;
  margin: 0 auto;
}
.page-hero-section h1,
.about-hero-section h1,
.privacy-hero-section h1,
.faq-hero h1 {
  font-family: var(--font-brand);
  font-size: clamp(1.5rem, 3.5vw, 2.2rem);
  font-weight: 700;
  line-height: 1.3;
  color: var(--c-ink);
  margin-bottom: 12px;
}
.page-lead {
  font-size: 1rem;
  color: var(--c-ink-soft);
  max-width: 640px;
}
.eyebrow-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--c-ink-mute);
  background: linear-gradient(145deg, var(--c-main-light), var(--c-main));
  border-radius: 20px;
  padding: 4px 12px;
  margin-bottom: 12px;
  box-shadow: var(--shadow-card);
}
.date-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 12px;
}
.page-date {
  font-size: 0.8rem;
  color: var(--c-ink-mute);
  background: rgba(255,255,255,0.5);
  padding: 3px 10px;
  border-radius: 20px;
}

/* ===== Feature Hero（并排）===== */
.feature-hero-section {
  display: flex;
  align-items: center;
  gap: 0;
  min-height: 40vh;
  padding: 0;
}
.feature-hero-media {
  flex: 0 0 40%;
  height: 40vh;
  min-height: 280px;
  overflow: hidden;
}
.feature-hero-img,
.feature-hero-placeholder {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 0;
}
.feature-hero-placeholder {
  background: linear-gradient(135deg, var(--c-accent), var(--c-main-dark));
}
.feature-hero-text {
  flex: 1 1 60%;
  padding: 40px 36px;
}
.feature-hero-text h1 {
  font-family: var(--font-brand);
  font-size: clamp(1.4rem, 3vw, 2rem);
  font-weight: 700;
  color: var(--c-ink);
  margin-bottom: 10px;
  line-height: 1.3;
}

/* ===== 页脚 ===== */
.site-footer {
  background: linear-gradient(145deg, var(--c-main-dark), var(--c-surface));
  padding: 28px 24px 16px;
  text-align: center;
}
.site-footer p {
  font-size: 0.9rem;
  color: var(--c-ink-soft);
  margin-bottom: 8px;
}
.site-footer p a {
  color: var(--c-ink);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 2px;
  margin: 0 4px;
}
.site-footer small {
  font-size: 0.75rem;
  color: var(--c-ink-mute);
  display: block;
  line-height: 1.5;
}
.footer-brand { font-family: var(--font-brand); }

/* ===== FAQ prose ===== */
.faq-prose h2 { color: var(--c-ink); }
.faq-prose h3 {
  color: var(--c-ink-soft);
  background: linear-gradient(145deg, rgba(245,224,232,0.5), rgba(200,224,244,0.5));
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  margin-bottom: 6px;
}

/* ===== 滚动揭示动效 ===== */
@media (prefers-reduced-motion: no-preference) {
  .child-card,
  .prose-area,
  .sidebar {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s ease, transform 0.5s ease, box-shadow var(--transition), border-color var(--transition);
  }
  .child-card.revealed,
  .prose-area.revealed,
  .sidebar.revealed {
    opacity: 1;
    transform: translateY(0);
  }
  .card-grid .child-card:nth-child(2) { transition-delay: 0.08s; }
  .card-grid .child-card:nth-child(3) { transition-delay: 0.16s; }
  .card-grid .child-card:nth-child(4) { transition-delay: 0.24s; }
  .card-grid .child-card:nth-child(5) { transition-delay: 0.32s; }
  .card-grid .child-card:nth-child(6) { transition-delay: 0.40s; }
}
@media (prefers-reduced-motion: reduce) {
  .child-card,
  .prose-area,
  .sidebar {
    opacity: 1 !important;
    transform: none !important;
    transition: box-shadow var(--transition), border-color var(--transition), transform var(--transition) !important;
  }
}

/* ===== 空提示 ===== */
.empty-tip {
  color: var(--c-ink-mute);
  font-size: 0.9rem;
  padding: 20px;
  text-align: center;
}

/* ===== 桌面端 ===== */
@media (min-width: 768px) {
  .site-nav { padding: 0 32px; }
  .nav-brand { display: block; }
  .site-nav ol {
    justify-content: center;
    flex-wrap: wrap;
    overflow-x: visible;
  }
  .site-nav ol li a { font-size: 0.85rem; }
  .bottom-nav-spacer { height: 80px; }

  .content-section { padding: 56px 40px; }
  .cards-section,
  .related-section,
  .other-features-section,
  .faq-guides-section,
  .about-links-section,
  .privacy-extra-section { padding: 48px 40px; }
}

@media (min-width: 1024px) {
  .hero-section { min-height: 70vh; }
  .hero-text { padding: 60px 60px 60px 30px; }
  .content-section { padding: 64px 60px; }
}

/* ===== 移动端适配 ===== */
@media (max-width: 767px) {
  .hero-section {
    flex-direction: column;
    min-height: auto;
  }
  .hero-media {
    flex: 0 0 auto;
    width: 100%;
    height: 45vw;
    min-height: 180px;
  }
  .hero-media::after { display: none; }
  .hero-text {
    padding: 28px 20px 24px;
    text-align: left;
  }
  .hero-lead { margin-left: 0; }
  .hero-eyebrow { text-align: left; }

  .content-wrap {
    flex-direction: column;
    gap: 24px;
  }
  .sidebar {
    position: static;
    flex: none;
    width: 100%;
  }
  .prose-area { padding: 24px 18px; }

  .feature-hero-section {
    flex-direction: column;
    min-height: auto;
  }
  .feature-hero-media {
    flex: 0 0 auto;
    width: 100%;
    height: 38vw;
    min-height: 160px;
  }
  .feature-hero-text {
    padding: 24px 20px;
  }

  .card-grid,
  .about-quick-links {
    grid-template-columns: 1fr;
  }

  .announce-bar { font-size: 0.72rem; }
}