:root {
  --bg-deep: #07080d;
  --bg-panel: #0f1118;
  --bg-card: #161922;
  --bg-elevated: #1c2030;
  --orange: #ff7a18;
  --orange-soft: #ff9a4d;
  --orange-glow: rgba(255, 122, 24, 0.35);
  --purple: #6b5cff;
  --purple-soft: rgba(107, 92, 255, 0.15);
  --text: #eef0f6;
  --text-muted: #8d94a8;
  --line: rgba(255, 255, 255, 0.07);
  --radius: 14px;
  --radius-lg: 22px;
  --header-h: 64px;
  --download-bar-h: 0px;
  --font-display: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --max: 1120px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + var(--download-bar-h) + 8px);
}

body {
  font-family: var(--font-body);
  background: var(--bg-deep);
  color: var(--text);
  line-height: 1.8;
  font-size: 15px;
  font-weight: 400;
  letter-spacing: 0.01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

body.has-top-bar {
  padding-top: var(--download-bar-h);
}

body.menu-open {
  overflow: hidden;
}

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

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

a:hover {
  color: var(--orange);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  height: var(--header-h);
  background: rgba(7, 8, 13, 0.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
}

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 11px;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-text strong {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: 0.06em;
}

.brand-text span {
  font-size: 0.72rem;
  color: var(--text-muted);
}

.nav-desktop {
  display: none;
  gap: 28px;
}

.nav-desktop a {
  color: var(--text-muted);
  font-size: 0.92rem;
}

.nav-desktop a.active,
.nav-desktop a:hover {
  color: var(--text);
}

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

.menu-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.25s ease;
}

.nav-mobile {
  display: none;
  position: fixed;
  inset: var(--header-h) 0 0 0;
  background: rgba(7, 8, 13, 0.98);
  padding: 24px;
  z-index: 1002;
}

.nav-mobile.open {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.nav-mobile a {
  color: var(--text);
  font-size: 1.05rem;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
}

.download-zone {
  padding: 18px 0 8px;
  background: linear-gradient(180deg, rgba(255, 122, 24, 0.06), transparent);
}

#ads {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  flex-wrap: wrap;
  background: transparent;
  margin: 10px 0;
  gap: 8px;
}

#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(24, 24, 24, 0.12);
  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(24, 24, 24, 0.18);
}

#ads figcaption,
#ads .caption {
  height: 15px;
  font-size: 11px;
  color: #666;
  text-align: center;
  max-width: 100px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.download-zone-label {
  text-align: center;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.fixed-download-bar {
  position: fixed;
  left: 0;
  right: 0;
  top: var(--header-h);
  z-index: 999;
  background: rgba(10, 12, 18, 0.97);
  border-bottom: 1px solid var(--line);
  padding: 8px 12px;
  transform: translateY(-110%);
  opacity: 0;
  pointer-events: none;
  transition: transform 0.3s ease, opacity 0.3s ease;
  backdrop-filter: blur(14px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
}

.fixed-download-bar.visible {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.fixed-download-bar .bar-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  max-width: var(--max);
  margin: 0 auto;
}

.fixed-download-bar .bar-item {
  width: calc(12.5% - 8px);
  min-width: 68px;
  max-width: 78px;
  text-align: center;
}

.fixed-download-bar .bar-item img {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  margin: 0 auto 4px;
  object-fit: cover;
}

.fixed-download-bar .bar-item span {
  display: block;
  font-size: 10px;
  color: var(--text-muted);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

@media (max-width: 768px) {
  .fixed-download-bar {
    top: calc(var(--header-h) + 8px);
    max-height: calc(100dvh - var(--header-h) - 8px);
    overflow-y: auto;
  }

  .fixed-download-bar .bar-item {
    width: calc(25% - 8px);
  }

  .nav-mobile.open {
    top: calc(var(--header-h) + var(--download-bar-h));
    height: calc(100dvh - var(--header-h) - var(--download-bar-h));
    overflow-y: auto;
  }

  .nav-mobile.open::before {
    content: "";
    position: sticky;
    top: -24px;
    display: block;
    height: 8px;
    margin: -24px -24px 16px;
    background: linear-gradient(90deg, rgba(255, 122, 24, 0.9), rgba(107, 92, 255, 0.9));
  }
}

.hero {
  position: relative;
  padding: 48px 0 64px;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: -120px;
  right: -80px;
  width: 420px;
  height: 420px;
  background: radial-gradient(circle, var(--orange-glow), transparent 70%);
  pointer-events: none;
}

.hero-grid {
  display: grid;
  gap: 40px;
  align-items: center;
}

.hero-copy h1 {
  font-family: var(--font-display);
  font-size: clamp(1.85rem, 5vw, 2.75rem);
  font-weight: 700;
  line-height: 1.35;
  letter-spacing: 0.02em;
  margin-bottom: 18px;
}

.hero-copy h1 em {
  font-style: normal;
  color: var(--orange);
}

.hero-lead {
  color: var(--text-muted);
  font-size: 1rem;
  margin-bottom: 24px;
  max-width: 540px;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 28px;
}

.hero-tags span {
  padding: 6px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 0.82rem;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.02);
}

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

.stat-box {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 12px;
  text-align: center;
}

.stat-box strong {
  display: block;
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--orange);
}

.stat-box span {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.hero-visual {
  position: relative;
  min-height: 380px;
  display: flex;
  justify-content: center;
  align-items: center;
}

.phone-stack {
  position: relative;
  width: min(100%, 340px);
  height: 420px;
}

.phone-stack .phone {
  position: absolute;
  width: 58%;
  border-radius: 22px;
  overflow: hidden;
  border: 2px solid rgba(255, 255, 255, 0.12);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.55);
  transition: transform 0.35s ease;
}

.phone-stack .phone:nth-child(1) {
  top: 8%;
  left: 0;
  z-index: 1;
  transform: rotate(-8deg);
}

.phone-stack .phone:nth-child(2) {
  top: 0;
  left: 22%;
  z-index: 3;
  transform: rotate(2deg);
}

.phone-stack .phone:nth-child(3) {
  top: 14%;
  right: 0;
  z-index: 2;
  transform: rotate(7deg);
}

.phone-stack .phone:nth-child(4) {
  bottom: 0;
  left: 28%;
  z-index: 4;
  width: 52%;
  transform: rotate(-3deg);
}

.section {
  padding: 56px 0;
}

.section-head {
  margin-bottom: 36px;
}

.section-label {
  display: inline-block;
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--orange);
  margin-bottom: 10px;
}

.section-head h2 {
  font-family: var(--font-display);
  font-size: clamp(1.45rem, 3.5vw, 2rem);
  font-weight: 700;
  letter-spacing: 0.02em;
  margin-bottom: 12px;
}

.section-head p {
  color: var(--text-muted);
  max-width: 680px;
}

.feature-row {
  display: grid;
  gap: 32px;
  align-items: center;
  margin-bottom: 48px;
}

.feature-row.reverse .feature-media {
  order: 2;
}

.feature-media img {
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.4);
}

.feature-body h3 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  margin-bottom: 14px;
  padding-left: 14px;
  border-left: 3px solid var(--orange);
}

.feature-body p {
  color: var(--text-muted);
  margin-bottom: 12px;
}

.feature-list {
  list-style: none;
  margin-top: 16px;
}

.feature-list li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 8px;
  color: var(--text-muted);
  font-size: 0.92rem;
}

.feature-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--orange);
}

.btn-download {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: 16px;
  padding: 12px 28px;
  background: linear-gradient(135deg, var(--orange), #ff5500);
  color: #fff;
  border: none;
  border-radius: 999px;
  font-size: 0.92rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn-download:hover {
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 10px 30px var(--orange-glow);
}

.highlights {
  display: grid;
  gap: 16px;
  grid-template-columns: 1fr;
}

.highlight-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 20px;
  position: relative;
  overflow: hidden;
}

.highlight-card::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--orange), var(--purple));
}

.highlight-card h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.highlight-card p {
  font-size: 0.88rem;
  color: var(--text-muted);
}

.prose-block {
  background: var(--bg-panel);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  margin-bottom: 32px;
}

.prose-block h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  margin-bottom: 16px;
  color: var(--text);
}

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

.prose-block a {
  color: var(--orange-soft);
}

.faq-list details {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 20px;
  margin-bottom: 12px;
}

.faq-list summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}

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

.faq-list p {
  margin-top: 12px;
  color: var(--text-muted);
  font-size: 0.92rem;
}

.cta-band {
  margin: 48px 0 64px;
  padding: 40px 28px;
  text-align: center;
  background: linear-gradient(135deg, rgba(255, 122, 24, 0.12), rgba(107, 92, 255, 0.08));
  border: 1px solid rgba(255, 122, 24, 0.2);
  border-radius: var(--radius-lg);
}

.cta-band h2 {
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.cta-band p {
  color: var(--text-muted);
  margin-bottom: 20px;
}

.site-footer {
  border-top: 1px solid var(--line);
  padding: 40px 0 32px;
  background: var(--bg-panel);
}

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

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.88rem;
  margin-top: 12px;
  max-width: 320px;
}

.footer-links h4 {
  font-size: 0.85rem;
  margin-bottom: 12px;
  color: var(--text);
}

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

.footer-links li {
  margin-bottom: 8px;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.88rem;
}

.footer-bottom {
  margin-top: 32px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.breadcrumb {
  padding: 18px 0 0;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.breadcrumb a {
  color: var(--text-muted);
}

.breadcrumb span {
  color: var(--text);
}

.page-hero {
  padding: 32px 0 24px;
}

.page-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  font-weight: 700;
  letter-spacing: 0.02em;
  margin-bottom: 10px;
}

.page-hero p {
  color: var(--text-muted);
}

.legal-content {
  padding: 24px 0 64px;
}

.legal-content h2 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 600;
  margin: 28px 0 12px;
}

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

.legal-content ul {
  padding-left: 20px;
  margin-bottom: 16px;
}

.error-page {
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 40px 20px 64px;
}

.error-page h1 {
  font-family: var(--font-display);
  font-size: 4rem;
  font-weight: 700;
  color: var(--orange);
  line-height: 1;
  margin-bottom: 12px;
}

.text-columns {
  display: grid;
  gap: 20px;
  margin-bottom: 40px;
}

.text-column-item {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px 22px;
}

.text-column-item h4 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text);
}

.text-column-item p {
  color: var(--text-muted);
  font-size: 0.92rem;
  margin-bottom: 10px;
}

.preview-gallery {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-bottom: 40px;
}

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

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

.preview-item figcaption {
  padding: 12px 14px;
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.5;
  border-top: 1px solid var(--line);
}

.seo-article {
  margin-bottom: 36px;
}

.seo-article h3 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 14px;
}

.seo-article p {
  color: var(--text-muted);
  margin-bottom: 12px;
}

.article-split {
  display: grid;
  gap: 32px;
  align-items: start;
  margin-bottom: 40px;
}

.error-page p {
  color: var(--text-muted);
  margin-bottom: 24px;
}

@media (min-width: 768px) {
  .nav-desktop {
    display: flex;
  }

  .menu-toggle {
    display: none;
  }

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

  .feature-row {
    grid-template-columns: 1fr 1fr;
  }

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

  .footer-grid {
    grid-template-columns: 1.4fr 1fr 1fr;
  }

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

  .preview-gallery {
    grid-template-columns: repeat(4, 1fr);
  }

  .article-split {
    grid-template-columns: 1.2fr 1fr;
  }
}

@media (min-width: 992px) {
  .phone-stack:hover .phone:nth-child(1) {
    transform: rotate(-10deg) translateY(-6px);
  }

  .phone-stack:hover .phone:nth-child(2) {
    transform: rotate(0deg) translateY(-10px);
  }

  .phone-stack:hover .phone:nth-child(3) {
    transform: rotate(9deg) translateY(-4px);
  }

  .phone-stack:hover .phone:nth-child(4) {
    transform: rotate(-5deg) translateY(-8px);
  }
}