/* 抖阴APP官网 - d-y.pics */
:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #14141f;
  --bg-card: #1a1a28;
  --accent-cyan: #25f4ee;
  --accent-magenta: #fe2c55;
  --text-primary: #f0f0f5;
  --text-secondary: #a0a0b8;
  --text-muted: #6b6b80;
  --border: #2a2a3a;
  --radius: 12px;
  --shadow: 0 4px 24px rgba(0,0,0,0.4);
  --max-width: 1200px;
  --header-h: 64px;
  --tabbar-h: 56px;
}

*, *::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; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10,10,15,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  height: var(--header-h);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
}

.logo-link {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text-primary);
  font-weight: 700;
  font-size: 1.25rem;
}

.logo-link:hover { color: var(--text-primary); }

.logo-link img { width: 40px; height: 40px; border-radius: 8px; }

.nav-main { display: flex; gap: 8px; list-style: none; }

.nav-main a {
  color: var(--text-secondary);
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 0.95rem;
}

.nav-main a:hover,
.nav-main a.active {
  color: var(--text-primary);
  background: var(--bg-card);
}

.btn-download {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: linear-gradient(135deg, var(--accent-magenta), #ff4466);
  color: #fff !important;
  padding: 10px 24px;
  border-radius: 24px;
  font-weight: 600;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
}

.btn-download:hover {
  color: #fff !important;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(254,44,85,0.4);
}

/* Hero */
.hero {
  padding: 60px 0 80px;
  background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(37,244,238,0.08) 0%, transparent 70%);
  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(254,44,85,0.08) 0%, transparent 70%);
  pointer-events: none;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero h1 {
  font-size: 2.5rem;
  line-height: 1.3;
  margin-bottom: 20px;
  background: linear-gradient(135deg, var(--text-primary), var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 32px;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 32px;
}

.badge {
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }

.btn-secondary {
  display: inline-flex;
  align-items: center;
  padding: 10px 24px;
  border-radius: 24px;
  border: 1px solid var(--border);
  color: var(--text-primary) !important;
  font-weight: 500;
  transition: border-color 0.2s, background 0.2s;
}

.btn-secondary:hover {
  border-color: var(--accent-cyan);
  background: var(--bg-card);
  color: var(--accent-cyan) !important;
}

.hero-image {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

/* Sections */
.section { padding: 72px 0; }

.section-alt { background: var(--bg-secondary); }

.section-header { text-align: center; margin-bottom: 48px; }

.section-header h2 {
  font-size: 2rem;
  margin-bottom: 12px;
}

.section-header p {
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto;
}

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

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 24px;
  transition: transform 0.2s, border-color 0.2s;
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-cyan);
}

.feature-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-magenta));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 16px;
}

.feature-card h3 { font-size: 1.15rem; margin-bottom: 10px; }
.feature-card p { color: var(--text-secondary); font-size: 0.95rem; }

/* Category showcase */
.category-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.category-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: transform 0.2s;
}

.category-card:hover { transform: scale(1.02); }

.category-card img { width: 100%; aspect-ratio: 9/16; object-fit: cover; object-position: top; }

.category-card .cat-label {
  padding: 12px 16px;
  font-weight: 600;
  font-size: 0.95rem;
  text-align: center;
}

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

.gallery-item {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  background: var(--bg-card);
}

.gallery-item img { width: 100%; aspect-ratio: 9/16; object-fit: cover; object-position: top; }

.gallery-item figcaption {
  padding: 14px 16px;
  font-size: 0.9rem;
  color: var(--text-secondary);
  text-align: center;
}

/* Content article */
.content-article {
  max-width: 860px;
  margin: 0 auto;
}

.content-article h2 {
  font-size: 1.6rem;
  margin: 40px 0 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--accent-magenta);
}

.content-article h3 {
  font-size: 1.25rem;
  margin: 28px 0 12px;
  color: var(--accent-cyan);
}

.content-article p { margin-bottom: 16px; color: var(--text-secondary); }

.content-article ul, .content-article ol {
  margin: 0 0 16px 24px;
  color: var(--text-secondary);
}

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

.content-article strong { color: var(--text-primary); }

/* 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: 16px;
  overflow: hidden;
}

.faq-item summary {
  padding: 20px 24px;
  cursor: pointer;
  font-weight: 600;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq-item summary::after { content: "+"; font-size: 1.2rem; color: var(--accent-cyan); }
.faq-item[open] summary::after { content: "−"; }

.faq-item .faq-answer {
  padding: 0 24px 20px;
  color: var(--text-secondary);
}

/* Download steps */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  counter-reset: step;
}

.step-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  position: relative;
}

.step-card::before {
  counter-increment: step;
  content: counter(step);
  display: block;
  width: 36px;
  height: 36px;
  line-height: 36px;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-magenta));
  border-radius: 50%;
  margin: 0 auto 16px;
  font-weight: 700;
  color: #fff;
}

.step-card h3 { font-size: 1rem; margin-bottom: 8px; }
.step-card p { color: var(--text-secondary); font-size: 0.9rem; }

/* Page layout */
.page-hero {
  padding: 48px 0;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  text-align: center;
}

.page-hero h1 { font-size: 2rem; margin-bottom: 8px; }
.page-hero p { color: var(--text-secondary); }

.page-content { padding: 48px 0 80px; }

.legal-content {
  max-width: 800px;
  margin: 0 auto;
}

.legal-content h2 {
  font-size: 1.3rem;
  margin: 32px 0 12px;
  color: var(--accent-cyan);
}

.legal-content p, .legal-content li {
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.legal-content ul, .legal-content ol { margin-left: 24px; margin-bottom: 16px; }

/* Error pages */
.error-page {
  min-height: calc(100vh - var(--header-h) - 200px);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 60px 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;
  margin-bottom: 16px;
}

.error-page h1 { font-size: 1.5rem; margin-bottom: 12px; }
.error-page p { color: var(--text-secondary); margin-bottom: 32px; }

/* Footer */
.site-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 48px 0 24px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-top: 12px;
  max-width: 320px;
}

.footer-col h4 {
  font-size: 0.95rem;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.footer-col ul { list-style: none; }

.footer-col li { margin-bottom: 10px; }

.footer-col a { color: var(--text-secondary); font-size: 0.9rem; }
.footer-col a:hover { color: var(--accent-cyan); }

.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-bottom p { color: var(--text-muted); font-size: 0.85rem; }

.footer-links { display: flex; gap: 20px; flex-wrap: wrap; }
.footer-links a { color: var(--text-muted); font-size: 0.85rem; }

/* 移动端底部导航栏 */
.mobile-tabbar {
  display: none;
}

@media (max-width: 768px) {
  body {
    padding-bottom: calc(var(--tabbar-h) + env(safe-area-inset-bottom, 0px));
  }

  .mobile-tabbar {
    display: flex;
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 200;
    height: calc(var(--tabbar-h) + env(safe-area-inset-bottom, 0px));
    padding-bottom: env(safe-area-inset-bottom, 0px);
    background: rgba(14, 14, 22, 0.98);
    backdrop-filter: blur(16px);
    border-top: 1px solid var(--border);
    box-shadow: 0 -4px 24px rgba(0, 0, 0, 0.35);
  }

  .mobile-tabbar .tab-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 3px;
    color: var(--text-muted);
    font-size: 0.7rem;
    padding: 6px 0;
    transition: color 0.2s;
    -webkit-tap-highlight-color: transparent;
  }

  .mobile-tabbar .tab-item svg {
    width: 22px;
    height: 22px;
    stroke-linecap: round;
    stroke-linejoin: round;
  }

  .mobile-tabbar .tab-item.active {
    color: var(--accent-magenta);
  }

  .mobile-tabbar .tab-item.active svg {
    filter: drop-shadow(0 0 6px rgba(254, 44, 85, 0.4));
  }

  .mobile-tabbar .tab-item:active {
    color: var(--accent-cyan);
  }

  /* 移动端页脚精简 */
  .site-footer {
    padding: 24px 0 16px;
    margin-bottom: 0;
  }

  .footer-grid {
    display: none;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 10px;
    border-top: none;
    padding-top: 0;
  }

  .footer-bottom p {
    font-size: 0.8rem;
    line-height: 1.5;
  }

  .footer-links {
    justify-content: center;
    gap: 8px 16px;
    width: 100%;
  }

  .footer-links a {
    font-size: 0.78rem;
    padding: 4px 0;
  }

  /* 精简页脚（404/502） */
  .site-footer.compact {
    padding: 16px 0;
  }
}

/* Breadcrumb */
.breadcrumb {
  padding: 16px 0;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.breadcrumb a { color: var(--text-secondary); }
.breadcrumb span { margin: 0 8px; }

/* Internal links box */
.internal-links {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin: 40px 0;
}

.internal-links h3 { font-size: 1rem; margin-bottom: 12px; }

.internal-links ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.internal-links a {
  background: var(--bg-secondary);
  padding: 6px 14px;
  border-radius: 6px;
  font-size: 0.9rem;
  border: 1px solid var(--border);
}

/* Responsive */
@media (max-width: 1024px) {
  .hero-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .category-grid { grid-template-columns: repeat(3, 1fr); }
  .gallery-grid { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  .nav-main { display: none; }
  .hero h1 { font-size: 1.8rem; }
  .hero { padding: 40px 0 56px; }
  .section { padding: 48px 0; }
  .features-grid,
  .category-grid,
  .gallery-grid,
  .steps { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .page-hero { padding: 32px 0; }
  .page-hero h1 { font-size: 1.6rem; }
  .page-content { padding: 32px 0 48px; }
  .error-page { min-height: auto; padding: 48px 20px 32px; }
  .error-code { font-size: 4.5rem; }
}

/* 广告栏 - 固定于导航下方 */
.ad-bar {
  position: sticky;
  top: var(--header-h);
  z-index: 90;
  background: rgba(20, 20, 31, 0.96);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: 10px 0;
}

.ad-bar .container {
  display: flex;
  justify-content: center;
}

#ads {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px;
  background: transparent;
}

#ads > div {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 70px;
  box-sizing: border-box;
}

#ads img {
  width: 65px;
  height: 65px;
  object-fit: cover;
  border-radius: 18px;
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.35);
  transition: transform 180ms ease, box-shadow 180ms ease;
  display: block;
  border: none;
  background: linear-gradient(135deg, #fff, #fff);
}

#ads a {
  display: inline-block;
  text-decoration: none;
  border-radius: 15px;
}

#ads img:hover {
  transform: translateY(-4px) scale(1.04);
  box-shadow: 0 10px 24px rgba(254, 44, 85, 0.25);
}

#ads figcaption,
#ads .caption {
  height: 15px;
  font-size: 11px;
  color: var(--text-secondary);
  text-align: center;
  max-width: 100px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  margin-top: 4px;
}