:root {
  --bg: #06060b;
  --bg-card: #101018;
  --bg-elevated: #161622;
  --border: rgba(255, 255, 255, 0.08);
  --text: #f2f2f7;
  --text-muted: #9ca3af;
  --purple: #8b5cf6;
  --purple-light: #a78bfa;
  --orange: #ff7a18;
  --orange-soft: #ff9a4d;
  --gradient: linear-gradient(135deg, #8b5cf6 0%, #ff7a18 100%);
  --header-h: 58px;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow: 0 20px 60px rgba(0, 0, 0, 0.45);
  --container: 1120px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.75;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
}

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

a { color: var(--purple-light); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--orange-soft); }

.container {
  width: min(100% - 32px, var(--container));
  margin-inline: auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(6, 6, 11, 0.92);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  gap: 16px;
}

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

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
}

.brand-text strong {
  display: block;
  font-size: 16px;
  letter-spacing: 0.04em;
}

.brand-text small {
  font-size: 11px;
  color: var(--text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.nav-desktop {
  display: none;
  gap: 4px;
}

.nav-desktop a {
  color: var(--text-muted);
  font-size: 14px;
  padding: 8px 14px;
  border-radius: 999px;
  transition: background 0.2s, color 0.2s;
}

.nav-desktop a:hover,
.nav-desktop a.active {
  color: var(--text);
  background: rgba(139, 92, 246, 0.15);
}

.menu-btn {
  display: flex;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.menu-btn span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.25s, opacity 0.25s;
}

.menu-btn.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-btn.open span:nth-child(2) { opacity: 0; }
.menu-btn.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.nav-mobile {
  display: none;
  position: fixed;
  inset: var(--header-h) 0 0 0;
  background: rgba(6, 6, 11, 0.97);
  padding: 24px;
  z-index: 999;
  flex-direction: column;
  gap: 4px;
}

.nav-mobile.open { display: flex; }

.nav-mobile a {
  color: var(--text);
  font-size: 16px;
  padding: 14px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}

.nav-mobile a.active {
  border-color: rgba(139, 92, 246, 0.4);
  background: rgba(139, 92, 246, 0.1);
}

/* Sticky download bar */
.sticky-apps {
  position: fixed;
  top: var(--header-h);
  left: 0;
  right: 0;
  z-index: 950;
  background: rgba(10, 10, 16, 0.96);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: 8px 12px;
  transform: translateY(-110%);
  opacity: 0;
  pointer-events: none;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.sticky-apps.visible {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.sticky-apps .bar-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 6px 4px;
  max-width: var(--container);
  margin: 0 auto;
}

.sticky-apps .bar-grid > div { display: flex; flex-direction: column; align-items: center; }

.sticky-apps .bar-grid img {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  object-fit: cover;
}

.sticky-apps .bar-grid .caption {
  font-size: 10px;
  color: var(--text-muted);
  text-align: center;
  max-width: 72px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  margin-top: 2px;
}

.sticky-apps .bar-grid a { display: block; line-height: 0; }

/* Ads section */
.ads-block {
  padding: 16px 0 8px;
  background: linear-gradient(180deg, rgba(139, 92, 246, 0.06) 0%, transparent 100%);
}

.ads-block .ads-title {
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 10px;
  letter-spacing: 0.06em;
}

#ads {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px 6px;
}

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

#ads img {
  width: 65px;
  height: 65px;
  object-fit: cover;
  border-radius: 16px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
  border: 1px solid var(--border);
}

#ads a { display: block; border-radius: 16px; }

#ads img:hover {
  transform: translateY(-3px) scale(1.03);
  box-shadow: 0 12px 28px rgba(139, 92, 246, 0.25);
}

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

/* Hero */
.hero {
  position: relative;
  padding: 48px 0 56px;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: -40% -20% auto -20%;
  height: 80%;
  background:
    radial-gradient(ellipse at 30% 40%, rgba(139, 92, 246, 0.22) 0%, transparent 55%),
    radial-gradient(ellipse at 70% 20%, rgba(255, 122, 24, 0.14) 0%, transparent 50%);
  pointer-events: none;
}

.hero-grid {
  display: grid;
  gap: 36px;
  align-items: center;
  position: relative;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: 999px;
  border: 1px solid rgba(139, 92, 246, 0.35);
  background: rgba(139, 92, 246, 0.1);
  font-size: 12px;
  color: var(--purple-light);
  margin-bottom: 18px;
  letter-spacing: 0.04em;
}

.hero-badge::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 8px var(--orange);
}

.hero h1 {
  font-size: clamp(26px, 6vw, 42px);
  line-height: 1.25;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.hero h1 em {
  font-style: normal;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-lead {
  color: var(--text-muted);
  font-size: 15px;
  max-width: 540px;
  margin-bottom: 24px;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 28px;
}

.hero-tags span {
  font-size: 12px;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  color: var(--text-muted);
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  max-width: 420px;
}

.hero-stats div {
  padding: 14px 12px;
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  border: 1px solid var(--border);
  text-align: center;
}

.hero-stats b {
  display: block;
  font-size: 20px;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-stats i {
  font-style: normal;
  font-size: 11px;
  color: var(--text-muted);
}

/* Phone stack hero visual */
.phone-cascade {
  position: relative;
  width: min(100%, 320px);
  height: 420px;
  margin: 0 auto;
}

.phone-item {
  position: absolute;
  width: 148px;
  border-radius: 22px;
  overflow: hidden;
  border: 2px solid rgba(255, 255, 255, 0.12);
  box-shadow: var(--shadow);
  background: #000;
}

.phone-item img { width: 100%; aspect-ratio: 9/19; object-fit: cover; }

.phone-item:nth-child(1) { top: 0; left: 0; transform: rotate(-8deg); z-index: 1; }
.phone-item:nth-child(2) { top: 24px; left: 88px; transform: rotate(4deg); z-index: 2; }
.phone-item:nth-child(3) { top: 120px; left: 20px; transform: rotate(-3deg); z-index: 3; }
.phone-item:nth-child(4) { top: 140px; left: 108px; transform: rotate(7deg); z-index: 4; }

/* Section common */
.section {
  padding: 56px 0;
}

.section-head {
  margin-bottom: 32px;
}

.section-label {
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--orange);
  margin-bottom: 8px;
}

.section-head h2 {
  font-size: clamp(22px, 4.5vw, 30px);
  line-height: 1.3;
  margin-bottom: 10px;
}

.section-head p {
  color: var(--text-muted);
  max-width: 640px;
}

/* Feature cards grid */
.feature-grid {
  display: grid;
  gap: 16px;
}

.feature-card {
  padding: 24px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
  transition: border-color 0.25s, transform 0.25s;
}

.feature-card:hover {
  border-color: rgba(139, 92, 246, 0.35);
  transform: translateY(-2px);
}

.feature-card .icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  background: rgba(139, 92, 246, 0.15);
  margin-bottom: 14px;
}

.feature-card h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 14px;
  color: var(--text-muted);
}

/* Editorial blocks (3:7 ratio) */
.editorial {
  display: grid;
  gap: 28px;
  margin-bottom: 40px;
  align-items: center;
}

.editorial.reverse .editorial-media { order: -1; }

.editorial-media {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  max-width: 280px;
  margin: 0 auto;
}

.editorial-media img {
  width: 100%;
  aspect-ratio: 9/19;
  object-fit: cover;
}

.editorial-body h3 {
  font-size: 20px;
  margin-bottom: 12px;
  line-height: 1.35;
}

.editorial-body p {
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 12px;
}

.editorial-body ul {
  margin: 12px 0 0 18px;
  color: var(--text-muted);
  font-size: 14px;
}

.editorial-body li { margin-bottom: 6px; }

/* Channel tabs showcase */
.channel-row {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.channel-chip {
  padding: 16px;
  border-radius: var(--radius-sm);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  text-align: center;
}

.channel-chip strong {
  display: block;
  font-size: 15px;
  margin-bottom: 4px;
}

.channel-chip span {
  font-size: 12px;
  color: var(--text-muted);
}

/* FAQ */
.faq-list { display: grid; gap: 12px; }

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

.faq-item summary {
  padding: 16px 18px;
  cursor: pointer;
  font-weight: 600;
  font-size: 15px;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

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

.faq-item summary::after {
  content: "+";
  color: var(--purple-light);
  font-size: 18px;
  transition: transform 0.2s;
}

.faq-item[open] summary::after { transform: rotate(45deg); }

.faq-item .faq-body {
  padding: 0 18px 16px;
  color: var(--text-muted);
  font-size: 14px;
}

/* CTA band */
.cta-band {
  padding: 48px 0;
  text-align: center;
  background: linear-gradient(180deg, transparent, rgba(139, 92, 246, 0.08), transparent);
}

.cta-band h2 {
  font-size: clamp(20px, 4vw, 28px);
  margin-bottom: 12px;
}

.cta-band p {
  color: var(--text-muted);
  margin-bottom: 20px;
  max-width: 520px;
  margin-inline: auto;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: 999px;
  background: var(--gradient);
  color: #fff;
  font-weight: 600;
  font-size: 15px;
  border: none;
  cursor: pointer;
  transition: opacity 0.2s, transform 0.2s;
}

.btn-primary:hover {
  opacity: 0.92;
  transform: translateY(-1px);
  color: #fff;
}

/* Text-only SEO blocks */
.prose-block {
  padding: 32px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
  margin-bottom: 28px;
}

.prose-block h3 {
  font-size: 18px;
  margin-bottom: 14px;
  color: var(--text);
}

.prose-block p {
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 12px;
}

.seo-columns {
  display: grid;
  gap: 16px;
  margin-bottom: 28px;
}

.seo-columns .prose-block { margin-bottom: 0; }

.guide-steps {
  display: grid;
  gap: 14px;
  margin: 24px 0 28px;
}

.guide-step {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 14px;
  padding: 18px;
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  border: 1px solid var(--border);
}

.guide-step-num {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 18px;
  background: rgba(139, 92, 246, 0.18);
  color: var(--purple-light);
}

.guide-step-body h4 {
  font-size: 16px;
  margin-bottom: 6px;
}

.guide-step-body p {
  color: var(--text-muted);
  font-size: 14px;
  margin: 0;
}

.keyword-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.keyword-tags span {
  font-size: 12px;
  padding: 5px 12px;
  border-radius: 999px;
  background: rgba(255, 122, 24, 0.1);
  border: 1px solid rgba(255, 122, 24, 0.25);
  color: var(--orange-soft);
}

/* Breadcrumb */
.breadcrumb {
  padding: 16px 0 0;
  font-size: 13px;
  color: var(--text-muted);
}

.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--purple-light); }
.breadcrumb span { color: var(--text); }

/* Subpage */
.page-hero {
  padding: 32px 0 24px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 32px;
}

.page-hero h1 {
  font-size: clamp(24px, 5vw, 32px);
  margin-bottom: 8px;
}

.page-hero p {
  color: var(--text-muted);
  font-size: 14px;
}

.page-content {
  padding-bottom: 64px;
}

.page-content h2 {
  font-size: 20px;
  margin: 28px 0 12px;
  color: var(--purple-light);
}

.page-content h3 {
  font-size: 17px;
  margin: 20px 0 10px;
}

.page-content p,
.page-content li {
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 10px;
}

.page-content ul,
.page-content ol {
  margin: 0 0 16px 20px;
}

/* Error pages */
.error-page {
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 48px 16px;
}

.error-code {
  font-size: 72px;
  font-weight: 800;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 12px;
}

.error-page h1 { font-size: 22px; margin-bottom: 10px; }
.error-page p { color: var(--text-muted); margin-bottom: 24px; max-width: 400px; }

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 40px 0 32px;
  background: var(--bg-card);
}

.footer-grid {
  display: grid;
  gap: 24px;
  margin-bottom: 28px;
}

.footer-brand img {
  width: 44px;
  border-radius: 10px;
  margin-bottom: 10px;
}

.footer-brand p {
  font-size: 13px;
  color: var(--text-muted);
  max-width: 280px;
}

.footer-links h4 {
  font-size: 14px;
  margin-bottom: 10px;
}

.footer-links a {
  display: block;
  font-size: 13px;
  color: var(--text-muted);
  padding: 4px 0;
}

.footer-bottom {
  padding-top: 20px;
  border-top: 1px solid var(--border);
  font-size: 12px;
  color: var(--text-muted);
  text-align: center;
}

/* Desktop */
@media (min-width: 768px) {
  .nav-desktop { display: flex; }
  .menu-btn { display: none; }

  .sticky-apps .bar-grid {
    grid-template-columns: repeat(8, 1fr);
  }

  .sticky-apps .bar-grid img {
    width: 52px;
    height: 52px;
  }

  .hero-grid {
    grid-template-columns: 1fr 1fr;
    gap: 48px;
  }

  .phone-cascade {
    width: 340px;
    height: 440px;
    margin-left: auto;
    margin-right: 0;
  }

  .phone-item { width: 168px; }
  .phone-item:nth-child(2) { left: 100px; }
  .phone-item:nth-child(4) { left: 124px; }

  .feature-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .editorial {
    grid-template-columns: 3fr 7fr;
    gap: 40px;
  }

  .editorial.reverse {
    grid-template-columns: 7fr 3fr;
  }

  .editorial.reverse .editorial-media { order: 0; }

  .editorial-media {
    max-width: none;
    margin: 0;
  }

  .channel-row {
    grid-template-columns: repeat(3, 1fr);
  }

  .footer-grid {
    grid-template-columns: 2fr 1fr 1fr;
  }

  .seo-columns {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .hero { padding: 64px 0 72px; }
  .section { padding: 72px 0; }
}