/* 抖阴APP官网 - 全局样式 */
:root {
  --bg-primary: #0a0a0a;
  --bg-secondary: #141414;
  --bg-card: #1a1a1a;
  --text-primary: #f5f5f5;
  --text-secondary: #b0b0b0;
  --accent-cyan: #00e5ff;
  --accent-magenta: #ff2d6a;
  --accent-red: #ff3b5c;
  --border: #2a2a2a;
  --max-width: 1100px;
  --radius: 10px;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.5);
  --header-height: 68px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.75;
  min-height: 100vh;
}

a { color: var(--accent-cyan); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent-magenta); }

img { max-width: 100%; height: auto; display: block; }

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 20px; }

/* 头部导航 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 10, 10, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  max-width: var(--max-width);
  margin: 0 auto;
  position: relative;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  padding: 0;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  cursor: pointer;
  flex-shrink: 0;
  -webkit-tap-highlight-color: transparent;
}

.nav-toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.2s ease;
}

.site-header.is-nav-open .nav-toggle-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.site-header.is-nav-open .nav-toggle-bar:nth-child(2) {
  opacity: 0;
}

.site-header.is-nav-open .nav-toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.logo-link { display: flex; align-items: center; gap: 12px; }
.logo-link img { width: 42px; height: 42px; }
.logo-text {
  font-size: 1.35rem;
  font-weight: 700;
  background: linear-gradient(90deg, var(--accent-cyan), #fff, var(--accent-magenta));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.main-nav { display: flex; gap: 6px; flex-wrap: wrap; }
.main-nav a {
  color: var(--text-secondary);
  padding: 8px 14px;
  border-radius: 6px;
  font-size: 0.95rem;
}
.main-nav a:hover, .main-nav a.active {
  color: var(--text-primary);
  background: var(--bg-card);
}

/* 按钮 */
.btn {
  display: inline-block;
  padding: 14px 32px;
  border-radius: 50px;
  font-weight: 600;
  font-size: 1rem;
  border: none;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent-magenta), var(--accent-red));
  color: #fff;
  box-shadow: 0 4px 20px rgba(255, 45, 106, 0.35);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 28px rgba(255, 45, 106, 0.5);
  color: #fff;
}
.btn-outline {
  border: 2px solid var(--accent-cyan);
  color: var(--accent-cyan);
  background: transparent;
}
.btn-outline:hover { background: rgba(0, 229, 255, 0.1); color: var(--accent-cyan); }

/* Hero */
.hero {
  padding: 60px 0 50px;
  text-align: center;
  background: radial-gradient(ellipse at 50% 0%, rgba(255, 45, 106, 0.12) 0%, transparent 60%),
              radial-gradient(ellipse at 80% 50%, rgba(0, 229, 255, 0.08) 0%, transparent 50%);
}
.hero h1 {
  font-size: clamp(1.8rem, 5vw, 2.6rem);
  line-height: 1.3;
  margin-bottom: 18px;
}
.hero-desc {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 720px;
  margin: 0 auto 30px;
}
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; margin-bottom: 40px; }
.hero-badges { display: flex; gap: 20px; justify-content: center; flex-wrap: wrap; }
.badge {
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 10px 20px;
  border-radius: var(--radius);
  font-size: 0.9rem;
  color: var(--text-secondary);
}
.badge strong { color: var(--accent-cyan); }

/* 内容区块 */
.section { padding: 50px 0; }
.section-alt { background: var(--bg-secondary); }
.section-title {
  font-size: 1.75rem;
  margin-bottom: 12px;
  text-align: center;
}
.section-subtitle {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: 36px;
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
}

/* 功能卡片 */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}
.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  transition: border-color 0.2s, transform 0.2s;
}
.feature-card:hover {
  border-color: var(--accent-magenta);
  transform: translateY(-3px);
}
.feature-card h3 {
  font-size: 1.15rem;
  margin-bottom: 10px;
  color: var(--accent-cyan);
}
.feature-card p { color: var(--text-secondary); font-size: 0.95rem; }

/* 截图展示 */
.screenshot-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}
.screenshot-item {
  background: var(--bg-card);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
}
.screenshot-item img { width: 100%; aspect-ratio: 9/16; object-fit: cover; object-position: top; }
.screenshot-item figcaption {
  padding: 14px 16px;
  font-size: 0.9rem;
  color: var(--text-secondary);
  border-top: 1px solid var(--border);
}
.screenshot-item figcaption strong { color: var(--text-primary); display: block; margin-bottom: 4px; }

/* 分类标签 */
.category-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  margin: 24px 0;
}
.tag {
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* 安装步骤 */
.steps { counter-reset: step; max-width: 760px; margin: 0 auto; }
.step-item {
  display: flex;
  gap: 20px;
  margin-bottom: 28px;
  align-items: flex-start;
}
.step-item::before {
  counter-increment: step;
  content: counter(step);
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-magenta));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.1rem;
}
.step-item h3 { font-size: 1.05rem; margin-bottom: 6px; }
.step-item p { color: var(--text-secondary); font-size: 0.95rem; }

/* FAQ */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 14px;
  overflow: hidden;
}
.faq-item summary {
  padding: 18px 22px;
  cursor: pointer;
  font-weight: 600;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.faq-item summary::after { content: "+"; font-size: 1.3rem; color: var(--accent-cyan); }
.faq-item[open] summary::after { content: "−"; }
.faq-item .faq-answer {
  padding: 0 22px 18px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  border-top: 1px solid var(--border);
  padding-top: 14px;
}

/* 文章正文 */
.article-content { max-width: 800px; margin: 0 auto; }
.article-content h1 { font-size: 2rem; margin-bottom: 20px; }
.article-content h2 { font-size: 1.35rem; margin: 32px 0 14px; color: var(--accent-cyan); }
.article-content h3 { font-size: 1.1rem; margin: 24px 0 10px; }
.article-content p { margin-bottom: 16px; color: var(--text-secondary); }
.article-content ul, .article-content ol { margin: 0 0 16px 24px; color: var(--text-secondary); }
.article-content li { margin-bottom: 8px; }
.article-content .update-date { color: var(--text-secondary); font-size: 0.9rem; margin-bottom: 30px; }

/* 内链提示 */
.internal-links {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin: 36px 0;
}
.internal-links h3 { font-size: 1.05rem; margin-bottom: 12px; }
.internal-links ul { list-style: none; margin: 0; }
.internal-links li { margin-bottom: 8px; }
.internal-links a::before { content: "→ "; color: var(--accent-magenta); }

/* 页脚 */
.site-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 40px 0 24px;
  margin-top: 60px;
}
.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 30px;
  margin-bottom: 30px;
}
.footer-col h4 { font-size: 1rem; margin-bottom: 14px; color: var(--text-primary); }
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 8px; }
.footer-col a { color: var(--text-secondary); font-size: 0.9rem; }
.footer-col a:hover { color: var(--accent-cyan); }
.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.85rem;
}

/* 错误页 */
.error-page {
  min-height: 80vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 40px 20px;
}
.error-code {
  font-size: 6rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-magenta));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
}
.error-page h1 { font-size: 1.5rem; margin: 16px 0 10px; }
.error-page p { color: var(--text-secondary); margin-bottom: 28px; }

/* 面包屑 */
.breadcrumb {
  padding: 16px 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
}
.breadcrumb a { color: var(--text-secondary); }
.breadcrumb a:hover { color: var(--accent-cyan); }
.breadcrumb span { margin: 0 8px; }

/* 响应式 */
@media (max-width: 768px) {
  :root { --header-height: 58px; }

  .header-inner {
    flex-wrap: nowrap;
    padding: 10px 16px;
    gap: 12px;
  }

  .logo-link { min-width: 0; flex: 1; }
  .logo-link img { width: 36px; height: 36px; }
  .logo-text { font-size: 1.15rem; }

  .nav-toggle { display: flex; }

  .main-nav {
    display: none;
    position: absolute;
    top: calc(100% + 1px);
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 4px;
    padding: 10px 12px 14px;
    background: rgba(10, 10, 10, 0.98);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.45);
    z-index: 101;
  }

  .site-header.is-nav-open .main-nav { display: flex; }

  .main-nav a {
    width: 100%;
    padding: 12px 14px;
    font-size: 0.95rem;
    border-radius: 8px;
    text-align: left;
  }

  .main-nav a.active {
    background: linear-gradient(90deg, rgba(255, 45, 106, 0.15), rgba(0, 229, 255, 0.08));
    border: 1px solid rgba(255, 45, 106, 0.25);
  }

  body.nav-open { overflow: hidden; }

  body.nav-open::before {
    content: "";
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.55);
    z-index: 98;
  }

  .hero { padding: 40px 0 30px; }
  .section { padding: 36px 0; }
}

/* 顶部固定广告栏 */
.ads-bar {
  position: sticky;
  top: var(--header-height);
  z-index: 99;
  background: rgba(10, 10, 10, 0.97);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: 8px 12px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.35);
}

#ads {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px 12px;
  background: transparent;
  margin: 0 auto;
  max-width: var(--max-width);
}

#ads > div {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 72px;
  box-sizing: border-box;
}

#ads img {
  width: 58px;
  height: 58px;
  object-fit: cover;
  border-radius: 14px;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.4);
  transition: transform 180ms ease, box-shadow 180ms ease;
  display: block;
  border: 1px solid var(--border);
  background: #fff;
}

#ads a {
  display: inline-block;
  text-decoration: none;
  border-radius: 14px;
}

#ads img:hover {
  transform: translateY(-3px) scale(1.06);
  box-shadow: 0 8px 20px rgba(255, 45, 106, 0.35);
}

#ads figcaption,
#ads .caption {
  height: 16px;
  line-height: 16px;
  font-size: 11px;
  color: var(--text-secondary);
  text-align: center;
  max-width: 72px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  margin-top: 4px;
}