:root {
  --bg: #0a0a0c;
  --bg-soft: #121216;
  --bg-card: #18181e;
  --line: #2a2a32;
  --text: #e8e6e3;
  --muted: #9a9690;
  --accent: #c41e2a;
  --accent-soft: #8b1520;
  --accent-glow: rgba(196, 30, 42, 0.35);
  --white: #ffffff;
  --radius: 12px;
  --max: 1120px;
  --font: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  background:
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(139, 21, 32, 0.25), transparent),
    radial-gradient(ellipse 60% 40% at 100% 50%, rgba(40, 20, 25, 0.4), transparent),
    var(--bg);
  color: var(--text);
  line-height: 1.75;
  min-height: 100vh;
}

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

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

a:hover {
  color: #e83a46;
}

ul {
  list-style: none;
}

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

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

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--white);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.04em;
}

.brand img {
  width: 44px;
  height: 44px;
  border-radius: 10px;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  align-items: center;
}

.nav a {
  color: var(--muted);
  font-size: 0.95rem;
}

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

.nav-cta {
  background: var(--accent);
  color: var(--white) !important;
  padding: 8px 16px;
  border-radius: 999px;
  font-weight: 600;
}

.nav-cta:hover {
  background: #e02a36;
}

.menu-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
  padding: 8px 12px;
  border-radius: 8px;
  cursor: pointer;
}

/* Hero */
.hero {
  padding: 48px 0 36px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: center;
}

.hero-badge {
  display: inline-block;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  color: var(--accent);
  border: 1px solid var(--accent-soft);
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 16px;
}

.hero h1 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  line-height: 1.25;
  margin-bottom: 16px;
  color: var(--white);
}

.hero-lead {
  color: var(--muted);
  font-size: 1.05rem;
  margin-bottom: 28px;
  max-width: 36em;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 20px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 10px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  font-size: 1rem;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-soft));
  color: var(--white);
  box-shadow: 0 8px 28px var(--accent-glow);
}

.btn-primary:hover {
  color: var(--white);
  filter: brightness(1.08);
}

.btn-ghost {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--line);
}

.btn-ghost:hover {
  border-color: var(--muted);
  color: var(--white);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 24px;
  color: var(--muted);
  font-size: 0.9rem;
}

.hero-meta strong {
  color: var(--text);
  font-weight: 600;
}

.hero-visual {
  position: relative;
}

.hero-visual img {
  border-radius: 16px;
  border: 1px solid var(--line);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.55);
}

.hero-float {
  position: absolute;
  right: -8px;
  bottom: -16px;
  width: 42%;
  border-radius: 12px;
  border: 2px solid var(--bg);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.5);
}

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

.section-alt {
  background: linear-gradient(180deg, transparent, rgba(24, 24, 30, 0.65), transparent);
}

.section-head {
  margin-bottom: 32px;
  max-width: 42em;
}

.section-head h2 {
  font-size: clamp(1.45rem, 3vw, 1.9rem);
  color: var(--white);
  margin-bottom: 10px;
}

.section-head p {
  color: var(--muted);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

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

.feature-card h3 {
  color: var(--white);
  font-size: 1.1rem;
  margin-bottom: 10px;
}

.feature-card p {
  color: var(--muted);
  font-size: 0.95rem;
}

.feature-num {
  display: inline-block;
  color: var(--accent);
  font-weight: 700;
  font-size: 0.85rem;
  margin-bottom: 8px;
  letter-spacing: 0.06em;
}

/* Showcase / screenshots */
.shot-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.shot-item {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.shot-item:hover {
  transform: translateY(-4px);
  border-color: var(--accent-soft);
}

.shot-item img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  background: #111;
}

.shot-item figcaption {
  padding: 12px 14px;
  font-size: 0.88rem;
  color: var(--muted);
}

.shot-wide {
  grid-column: span 2;
}

.shot-wide img {
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

/* Two column content */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: center;
}

.split-reverse .split-text {
  order: 2;
}

.split-media img {
  border-radius: var(--radius);
  border: 1px solid var(--line);
}

.split-text h2 {
  color: var(--white);
  font-size: 1.55rem;
  margin-bottom: 12px;
}

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

.split-text ul {
  margin: 12px 0 18px;
}

.split-text li {
  position: relative;
  padding-left: 18px;
  color: var(--text);
  margin-bottom: 8px;
}

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

/* Article / SEO long content */
.prose {
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: clamp(24px, 4vw, 40px);
}

.prose h2 {
  color: var(--white);
  font-size: 1.45rem;
  margin: 28px 0 12px;
}

.prose h2:first-child {
  margin-top: 0;
}

.prose h3 {
  color: var(--white);
  font-size: 1.15rem;
  margin: 22px 0 10px;
}

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

.prose a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.prose ul,
.prose ol {
  margin: 0 0 16px 1.2em;
  color: var(--muted);
}

.prose li {
  margin-bottom: 8px;
  list-style: disc;
}

.prose ol li {
  list-style: decimal;
}

.toc {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 22px;
  margin-bottom: 28px;
}

.toc strong {
  display: block;
  color: var(--white);
  margin-bottom: 10px;
}

.toc a {
  display: block;
  color: var(--muted);
  padding: 4px 0;
}

.toc a:hover {
  color: var(--accent);
}

/* Steps */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  counter-reset: step;
}

.step {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  counter-increment: step;
}

.step::before {
  content: "0" counter(step);
  display: block;
  color: var(--accent);
  font-weight: 700;
  margin-bottom: 10px;
}

.step h3 {
  color: var(--white);
  font-size: 1.05rem;
  margin-bottom: 8px;
}

.step p {
  color: var(--muted);
  font-size: 0.92rem;
}

/* FAQ */
.faq details {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 16px 18px;
  margin-bottom: 10px;
}

.faq summary {
  cursor: pointer;
  color: var(--white);
  font-weight: 600;
  list-style: none;
}

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

.faq details[open] summary {
  margin-bottom: 10px;
  color: var(--accent);
}

.faq details p {
  color: var(--muted);
}

/* Page banner for inner pages */
.page-banner {
  padding: 40px 0 20px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}

.page-banner h1 {
  font-size: clamp(1.6rem, 3.5vw, 2.2rem);
  color: var(--white);
  margin-bottom: 10px;
}

.page-banner p {
  color: var(--muted);
  max-width: 40em;
}

.breadcrumb {
  font-size: 0.88rem;
  color: var(--muted);
  margin-bottom: 14px;
}

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

.breadcrumb a:hover {
  color: var(--accent);
}

.legal-content {
  max-width: 820px;
  margin: 0 auto 60px;
}

.legal-content h2 {
  color: var(--white);
  font-size: 1.25rem;
  margin: 28px 0 10px;
}

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

.legal-content ul {
  margin-left: 1.2em;
  margin-bottom: 16px;
}

.legal-content li {
  list-style: disc;
}

/* Error pages */
.error-page {
  min-height: 70vh;
  display: flex;
  align-items: center;
  text-align: center;
  padding: 60px 0;
}

.error-page h1 {
  font-size: clamp(3rem, 10vw, 5rem);
  color: var(--accent);
  line-height: 1;
  margin-bottom: 12px;
}

.error-page h2 {
  color: var(--white);
  margin-bottom: 12px;
}

.error-page p {
  color: var(--muted);
  margin-bottom: 28px;
}

/* Download band */
.download-band {
  background:
    linear-gradient(135deg, rgba(196, 30, 42, 0.18), transparent 55%),
    var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: clamp(28px, 5vw, 48px);
  text-align: center;
}

.download-band h2 {
  color: var(--white);
  margin-bottom: 10px;
}

.download-band p {
  color: var(--muted);
  margin-bottom: 22px;
}

.download-band .cta-row {
  justify-content: center;
}

/* Related links */
.related {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.related a {
  display: block;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 16px 18px;
  color: var(--text);
}

.related a:hover {
  border-color: var(--accent);
  color: var(--white);
}

.related span {
  display: block;
  color: var(--muted);
  font-size: 0.85rem;
  margin-top: 4px;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--line);
  background: #070709;
  padding: 40px 0 28px;
  margin-top: 40px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 28px;
  margin-bottom: 28px;
}

.footer-brand {
  display: flex;
  gap: 12px;
  align-items: flex-start;
}

.footer-brand img {
  width: 48px;
  height: 48px;
  border-radius: 10px;
}

.footer-brand h3 {
  color: var(--white);
  font-size: 1.05rem;
  margin-bottom: 6px;
}

.footer-brand p {
  color: var(--muted);
  font-size: 0.9rem;
}

.footer-col h4 {
  color: var(--white);
  font-size: 0.95rem;
  margin-bottom: 12px;
}

.footer-col a {
  display: block;
  color: var(--muted);
  padding: 4px 0;
  font-size: 0.92rem;
}

.footer-col a:hover {
  color: var(--accent);
}

.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 18px;
  color: var(--muted);
  font-size: 0.85rem;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  justify-content: space-between;
}

/* Mobile */
@media (max-width: 900px) {
  .menu-toggle {
    display: inline-flex;
  }

  .nav {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    background: rgba(12, 12, 15, 0.98);
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    align-items: stretch;
    padding: 12px 16px 18px;
    gap: 0;
  }

  .nav.open {
    display: flex;
  }

  .nav a {
    padding: 12px 8px;
    border-bottom: 1px solid var(--line);
  }

  .nav-cta {
    margin-top: 10px;
    text-align: center;
    border-bottom: none !important;
  }

  .hero-grid,
  .split,
  .feature-grid,
  .footer-grid,
  .related {
    grid-template-columns: 1fr;
  }

  .split-reverse .split-text {
    order: 0;
  }

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

  .shot-wide {
    grid-column: span 2;
  }

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

  .hero-float {
    width: 38%;
    right: 8px;
    bottom: -12px;
  }
}

@media (max-width: 560px) {
  .shot-grid {
    grid-template-columns: 1fr 1fr;
    gap: 10px;
  }

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

  .hero {
    padding-top: 28px;
  }

  .section {
    padding: 40px 0;
  }
}