/* 抖阴官方网站 — 霓虹影院风格 · 移动端优先 */
:root {
  --bg-void: #06060e;
  --bg-panel: #0e0e1a;
  --bg-card: #141428;
  --bg-glass: rgba(14, 14, 26, 0.88);
  --accent-cyan: #00e5f0;
  --accent-magenta: #ff2d6a;
  --accent-amber: #ffb020;
  --accent-violet: #7c3aed;
  --text-primary: #ececf4;
  --text-secondary: #9898ae;
  --text-dim: #5c5c72;
  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-glow: rgba(0, 229, 240, 0.25);
  --nav-h: 58px;
  --ads-sticky-h: 96px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --shadow-neon: 0 0 40px rgba(0, 229, 240, 0.08);
  --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  --max-w: 1080px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-void);
  color: var(--text-primary);
  line-height: 1.75;
  font-size: 15px;
  overflow-x: hidden;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent-cyan); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent-amber); }

/* ── 顶栏 ── */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  height: var(--nav-h);
  background: var(--bg-glass);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--border-subtle);
}

.header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 16px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text-primary);
  flex-shrink: 0;
}

.brand-link img { width: 36px; height: 36px; border-radius: 10px; }
.brand-link span {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.04em;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-magenta));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.site-nav { display: none; }
.site-nav a {
  color: var(--text-secondary);
  font-size: 14px;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
}
.site-nav a:hover, .site-nav a.active { color: var(--text-primary); background: rgba(255,255,255,0.05); }

.nav-toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform 0.25s;
}

.btn-download {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  background: linear-gradient(135deg, var(--accent-magenta), var(--accent-violet));
  color: #fff;
  font-size: 13px;
  font-weight: 600;
  border-radius: 50px;
  border: none;
  cursor: pointer;
  white-space: nowrap;
  box-shadow: 0 4px 20px rgba(255, 45, 106, 0.35);
  transition: transform 0.2s, box-shadow 0.2s;
}
.btn-download:hover { transform: translateY(-1px); box-shadow: 0 6px 28px rgba(255, 45, 106, 0.5); color: #fff; }

/* ── 粘性广告条 ── */
.ads-sticky-bar {
  position: fixed;
  top: var(--nav-h);
  left: 0; right: 0;
  z-index: 999;
  background: var(--bg-glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-subtle);
  padding: 10px 12px;
  visibility: hidden;
  opacity: 0;
  transition: opacity 0.25s ease, visibility 0.25s ease;
  pointer-events: none;
  will-change: opacity;
}
.ads-sticky-bar.visible {
  visibility: visible;
  opacity: 1;
  pointer-events: auto;
}

#ads, #ads-sticky {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px 4px;
  max-width: 480px;
  margin: 0 auto;
}
.ads-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: calc(25% - 4px);
  min-width: 72px;
  max-width: 90px;
}
.ads-item figure { display: flex; flex-direction: column; align-items: center; margin: 0; }
.ads-item img {
  width: 58px; height: 58px;
  object-fit: cover;
  border-radius: 16px;
  box-shadow: 0 4px 16px rgba(0,0,0,0.3);
  transition: transform 0.18s;
}
.ads-item a:hover img { transform: scale(1.06); }
.ads-caption {
  font-size: 10px;
  color: var(--text-dim);
  text-align: center;
  margin-top: 4px;
  max-width: 72px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.ads-zone-wrap {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 16px;
  background: linear-gradient(180deg, rgba(124,58,237,0.06) 0%, transparent 100%);
  border-bottom: 1px solid var(--border-subtle);
}
.ads-zone-label {
  text-align: center;
  font-size: 12px;
  color: var(--text-dim);
  margin-bottom: 10px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* ── Hero ── */
.hero {
  position: relative;
  min-height: 88vh;
  display: flex;
  align-items: center;
  padding: calc(var(--nav-h) + 32px) 20px 48px;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 20% 40%, rgba(124,58,237,0.18) 0%, transparent 60%),
    radial-gradient(ellipse 60% 50% at 80% 20%, rgba(0,229,240,0.12) 0%, transparent 55%),
    radial-gradient(ellipse 50% 40% at 60% 80%, rgba(255,45,106,0.1) 0%, transparent 50%),
    var(--bg-void);
  z-index: 0;
}
.hero-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 2px,
    rgba(255,255,255,0.012) 2px,
    rgba(255,255,255,0.012) 4px
  );
  pointer-events: none;
}
.hero-content {
  position: relative;
  z-index: 1;
  max-width: var(--max-w);
  margin: 0 auto;
  width: 100%;
}
.hero-badge {
  display: inline-block;
  padding: 5px 14px;
  border: 1px solid var(--border-glow);
  border-radius: 50px;
  font-size: 12px;
  color: var(--accent-cyan);
  margin-bottom: 20px;
  background: rgba(0,229,240,0.06);
}
.hero h1 {
  font-size: clamp(26px, 7vw, 42px);
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}
.hero h1 em {
  font-style: normal;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-amber));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-desc {
  font-size: 15px;
  color: var(--text-secondary);
  max-width: 520px;
  margin-bottom: 28px;
  line-height: 1.8;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 0; }
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  background: linear-gradient(135deg, var(--accent-cyan), #00b8c8);
  color: #06060e;
  font-weight: 700;
  font-size: 15px;
  border-radius: 50px;
  border: none;
  cursor: pointer;
  box-shadow: 0 4px 24px rgba(0,229,240,0.3);
}
.btn-primary:hover { color: #06060e; filter: brightness(1.08); }
.btn-outline {
  display: inline-flex;
  align-items: center;
  padding: 14px 24px;
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  font-size: 14px;
  border-radius: 50px;
  background: rgba(255,255,255,0.03);
}
.btn-outline:hover { border-color: var(--accent-cyan); color: var(--accent-cyan); }

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 40px;
  padding-top: 28px;
  border-top: 1px solid var(--border-subtle);
}
.stat-item { text-align: center; }
.stat-num {
  font-size: 22px;
  font-weight: 800;
  color: var(--accent-amber);
  display: block;
}
.stat-label { font-size: 11px; color: var(--text-dim); margin-top: 2px; }

/* ── 通用区块 ── */
.section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 48px 20px;
}
.section-header { margin-bottom: 32px; }
.section-tag {
  font-size: 11px;
  letter-spacing: 0.15em;
  color: var(--accent-magenta);
  text-transform: uppercase;
  margin-bottom: 8px;
  display: block;
}
.section-header h2 {
  font-size: clamp(22px, 5vw, 30px);
  font-weight: 700;
  line-height: 1.3;
}

/* 3:7 图文模块 */
.media-block {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-bottom: 40px;
  padding: 24px;
  background: var(--bg-panel);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle);
}
.media-block.reverse .media-visual { order: -1; }
.media-visual {
  flex: 0 0 auto;
  width: 100%;
  position: relative;
}
.media-visual img {
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-neon);
  border: 1px solid var(--border-subtle);
}
.media-visual figcaption {
  font-size: 11px;
  color: var(--text-dim);
  text-align: center;
  margin-top: 8px;
}
.media-body { flex: 1; }
.media-body h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-primary);
}
.media-body p {
  color: var(--text-secondary);
  font-size: 14px;
  margin-bottom: 12px;
}
.media-body p:last-child { margin-bottom: 0; }
.media-body a.inline-link {
  color: var(--accent-cyan);
  border-bottom: 1px dashed rgba(0,229,240,0.4);
}

/* 功能网格 */
.feature-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}
.feature-card {
  padding: 20px;
  background: var(--bg-card);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  transition: border-color 0.25s;
}
.feature-card:hover { border-color: var(--border-glow); }
.feature-icon {
  width: 40px; height: 40px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  margin-bottom: 12px;
  background: linear-gradient(135deg, rgba(124,58,237,0.2), rgba(0,229,240,0.1));
}
.feature-card h4 { font-size: 15px; font-weight: 600; margin-bottom: 6px; }
.feature-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.65; }

/* FAQ */
.faq-list { display: flex; flex-direction: column; gap: 10px; }
.faq-item {
  background: var(--bg-panel);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  overflow: hidden;
}
.faq-q {
  width: 100%;
  text-align: left;
  padding: 16px 18px;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  font-family: inherit;
}
.faq-q::after {
  content: "+";
  font-size: 18px;
  color: var(--accent-cyan);
  flex-shrink: 0;
  transition: transform 0.25s;
}
.faq-item.open .faq-q::after { transform: rotate(45deg); }
.faq-a {
  display: none;
  padding: 0 18px 16px;
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.7;
}
.faq-item.open .faq-a { display: block; }

/* CTA 条 */
.cta-strip {
  margin: 0 20px 48px;
  max-width: calc(var(--max-w) - 40px);
  margin-left: auto;
  margin-right: auto;
  padding: 32px 24px;
  text-align: center;
  background: linear-gradient(135deg, rgba(124,58,237,0.15), rgba(255,45,106,0.1));
  border-radius: var(--radius-lg);
  border: 1px solid rgba(124,58,237,0.25);
}
.cta-strip h3 { font-size: 20px; margin-bottom: 10px; }
.cta-strip p { font-size: 14px; color: var(--text-secondary); margin-bottom: 20px; }

/* 纯文案 SEO 模块 */
.prose-block {
  padding: 28px 24px;
  background: var(--bg-panel);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle);
  margin-bottom: 28px;
}
.prose-block h3 {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--text-primary);
}
.prose-block p {
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.85;
  margin-bottom: 12px;
}
.prose-block p:last-child { margin-bottom: 0; }
.prose-block a { border-bottom: 1px dashed rgba(0,229,240,0.35); }

.text-columns {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-bottom: 32px;
}
.text-col {
  padding: 22px;
  background: var(--bg-card);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
}
.text-col h4 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--accent-cyan);
}
.text-col p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.75;
}

/* 内页 */
.page-hero {
  padding: calc(var(--nav-h) + 40px) 20px 32px;
  text-align: center;
  background: linear-gradient(180deg, rgba(124,58,237,0.08) 0%, transparent 100%);
}
.page-hero h1 { font-size: clamp(24px, 5vw, 34px); font-weight: 700; margin-bottom: 8px; }
.page-hero p { color: var(--text-secondary); font-size: 14px; }

.prose {
  max-width: 760px;
  margin: 0 auto;
  padding: 32px 20px 56px;
}
.prose h2 {
  font-size: 18px;
  font-weight: 700;
  margin: 28px 0 12px;
  color: var(--accent-cyan);
}
.prose h2:first-child { margin-top: 0; }
.prose p, .prose li {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 12px;
  line-height: 1.8;
}
.prose ul, .prose ol { padding-left: 20px; margin-bottom: 16px; }
.prose a { border-bottom: 1px dashed rgba(0,229,240,0.3); }

/* 404 / 502 */
.error-page {
  min-height: 80vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: calc(var(--nav-h) + 24px) 20px 48px;
  text-align: center;
}
.error-code {
  font-size: 80px;
  font-weight: 900;
  line-height: 1;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-magenta));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.error-page h1 { font-size: 22px; margin: 16px 0 8px; }
.error-page p { color: var(--text-secondary); font-size: 14px; margin-bottom: 24px; max-width: 400px; }

/* 页脚 */
.site-footer {
  background: var(--bg-panel);
  border-top: 1px solid var(--border-subtle);
  padding: 40px 20px 28px;
}
.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}
.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 20px;
}
.footer-brand img { width: 32px; height: 32px; border-radius: 8px; }
.footer-brand span { font-weight: 700; font-size: 15px; }
.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin-bottom: 20px;
}
.footer-links a { font-size: 13px; color: var(--text-secondary); }
.footer-links a:hover { color: var(--accent-cyan); }
.footer-copy {
  font-size: 12px;
  color: var(--text-dim);
  line-height: 1.6;
  padding-top: 16px;
  border-top: 1px solid var(--border-subtle);
}

/* ── 响应式 ── */
@media (min-width: 640px) {
  .text-columns { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .media-block {
    flex-direction: row;
    align-items: flex-start;
    gap: 28px;
  }
  .media-visual { width: 30%; flex-shrink: 0; }
  .media-body { width: 70%; }
  .media-block.reverse { flex-direction: row-reverse; }
}

@media (min-width: 768px) {
  .nav-toggle { display: none; }
  .site-nav {
    display: flex;
    align-items: center;
    gap: 4px;
  }
  .feature-grid { grid-template-columns: repeat(3, 1fr); }
  .hero { min-height: 75vh; }
}

@media (max-width: 767px) {
  .btn-download,
  .nav-dl-link { display: none !important; }

  .site-nav {
    position: fixed;
    top: var(--nav-h);
    left: 0; right: 0;
    background: var(--bg-glass);
    backdrop-filter: blur(18px);
    flex-direction: column;
    padding: 12px;
    border-bottom: 1px solid var(--border-subtle);
    transform: translateY(-120%);
    opacity: 0;
    transition: transform 0.3s, opacity 0.3s;
    display: flex;
  }
  .site-nav.open {
    transform: translateY(0);
    opacity: 1;
  }
  .site-nav a { width: 100%; padding: 12px 16px; }
}