:root {
  --bg: #0a0a0b;
  --bg-2: #121214;
  --bg-3: #1a1a1e;
  --text: #f2f2f2;
  --text-muted: #a8a8b0;
  --accent: #c41e2a;
  --accent-hover: #e02836;
  --line: rgba(255, 255, 255, 0.08);
  --green: #3ecf5a;
  --max: 1100px;
  --radius: 10px;
  --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(196, 30, 42, 0.18), transparent),
    radial-gradient(ellipse 60% 40% at 100% 50%, rgba(196, 30, 42, 0.06), transparent),
    var(--bg);
  color: var(--text);
  line-height: 1.75;
  font-size: 16px;
  min-height: 100vh;
}

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

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

a:hover {
  color: #ff6b75;
}

.container {
  width: min(100% - 32px, var(--max));
  margin: 0 auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 10, 11, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}

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

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

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

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

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

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

.nav-cta {
  background: var(--accent);
  color: #fff !important;
  padding: 8px 16px;
  border-radius: 6px;
  font-weight: 600;
}

.nav-cta:hover {
  background: var(--accent-hover);
  color: #fff !important;
}

.menu-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
  width: 40px;
  height: 40px;
  padding: 0;
  border-radius: 8px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
}

.menu-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--text);
  border-radius: 1px;
  transition: transform 0.2s, opacity 0.2s;
}

.menu-toggle.is-open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-toggle.is-open span:nth-child(2) {
  opacity: 0;
}

.menu-toggle.is-open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Hero */
.hero {
  padding: 48px 0 36px;
  border-bottom: 1px solid var(--line);
}

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

.hero h1 {
  font-size: clamp(1.6rem, 3.5vw, 2.35rem);
  line-height: 1.35;
  margin-bottom: 14px;
  font-weight: 800;
}

.hero .lead {
  color: var(--text-muted);
  font-size: 1.05rem;
  margin-bottom: 24px;
  max-width: 36em;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 18px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 22px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.98rem;
  border: none;
  cursor: pointer;
  transition: background 0.2s, transform 0.15s;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
}

.btn-secondary {
  background: var(--bg-3);
  color: var(--text);
  border: 1px solid var(--line);
}

.btn-secondary:hover {
  border-color: rgba(255, 255, 255, 0.2);
  color: var(--text);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  color: var(--text-muted);
  font-size: 0.88rem;
}

.hero-meta span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.hero-meta i {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--green);
  display: inline-block;
}

.hero-visual {
  position: relative;
}

.hero-visual img {
  border-radius: 12px;
  border: 1px solid var(--line);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.45);
  width: 100%;
  max-width: 320px;
  margin: 0 auto;
}

/* Sections */
.section {
  padding: 56px 0;
  border-bottom: 1px solid var(--line);
}

.section-head {
  margin-bottom: 28px;
  max-width: 42em;
}

.section-head h2 {
  font-size: clamp(1.35rem, 2.5vw, 1.85rem);
  margin-bottom: 10px;
  line-height: 1.35;
}

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

.section-body {
  color: var(--text-muted);
}

.section-body h3 {
  color: var(--text);
  font-size: 1.2rem;
  margin: 28px 0 12px;
}

.section-body h4 {
  color: var(--text);
  font-size: 1.05rem;
  margin: 22px 0 10px;
}

.section-body p {
  margin-bottom: 14px;
}

.section-body ul,
.section-body ol {
  margin: 0 0 16px 1.25em;
}

.section-body li {
  margin-bottom: 8px;
}

.section-body strong {
  color: var(--text);
  font-weight: 600;
}

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

.feature-card {
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.2s, transform 0.2s;
}

.feature-card:hover {
  border-color: rgba(196, 30, 42, 0.45);
  transform: translateY(-2px);
}

.feature-card img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  background: var(--bg-3);
}

.feature-card .cap {
  padding: 14px 16px 16px;
}

.feature-card h3 {
  font-size: 1rem;
  margin: 0 0 6px;
  color: var(--text);
}

.feature-card p {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin: 0;
  line-height: 1.55;
}

.shot-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin: 24px 0;
}

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

.shot-row.cols-2 {
  grid-template-columns: repeat(2, 1fr);
  max-width: 640px;
}

.shot {
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

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

.shot figcaption {
  padding: 10px 12px;
  font-size: 0.82rem;
  color: var(--text-muted);
  text-align: center;
}

/* Download box */
.download-box {
  background: linear-gradient(145deg, var(--bg-3), var(--bg-2));
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 28px;
  text-align: center;
}

.download-box h2 {
  margin-bottom: 10px;
}

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

.download-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

/* Breadcrumb / page */
.page-hero {
  padding: 36px 0 24px;
  border-bottom: 1px solid var(--line);
}

.page-hero h1 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  margin-bottom: 8px;
}

.breadcrumb {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 12px;
}

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

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

.prose {
  padding: 40px 0 56px;
  max-width: 760px;
}

.prose h2 {
  font-size: 1.35rem;
  margin: 32px 0 12px;
}

.prose h3 {
  font-size: 1.1rem;
  margin: 24px 0 10px;
}

.prose p,
.prose li {
  color: var(--text-muted);
}

.prose p {
  margin-bottom: 14px;
}

.prose ul,
.prose ol {
  margin: 0 0 16px 1.25em;
}

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

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

/* Error pages */
.error-page {
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 48px 16px;
}

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

.error-page h2 {
  margin-bottom: 12px;
}

.error-page p {
  color: var(--text-muted);
  margin-bottom: 24px;
  max-width: 28em;
}

/* TOC */
.toc {
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 20px;
  margin: 20px 0 28px;
}

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

.toc ol {
  margin: 0 0 0 1.2em;
  color: var(--text-muted);
}

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

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

/* FAQ */
.faq-item {
  border-bottom: 1px solid var(--line);
  padding: 16px 0;
}

.faq-item h3 {
  font-size: 1.05rem;
  margin: 0 0 8px;
  color: var(--text);
}

.faq-item p {
  margin: 0;
  color: var(--text-muted);
}

/* Footer */
.site-footer {
  padding: 40px 0 28px;
  background: var(--bg-2);
  border-top: 1px solid var(--line);
  margin-top: auto;
}

.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 {
  font-size: 1.05rem;
  margin-bottom: 6px;
}

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

.footer-col h4 {
  font-size: 0.92rem;
  margin-bottom: 12px;
  color: var(--text);
}

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

.footer-col a {
  color: var(--text-muted);
  font-size: 0.88rem;
  display: block;
  padding: 4px 0;
}

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

.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 18px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  justify-content: space-between;
  color: var(--text-muted);
  font-size: 0.82rem;
}

.internal-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  font-size: 0.9rem;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 16px 0;
}

.tag {
  background: var(--bg-3);
  border: 1px solid var(--line);
  color: var(--text-muted);
  padding: 4px 12px;
  border-radius: 999px;
  font-size: 0.82rem;
}

/* Mobile */
@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }

  .hero-visual {
    order: -1;
  }

  .hero-visual img {
    max-width: 240px;
  }

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

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

  .shot-row.cols-3 {
    grid-template-columns: repeat(2, 1fr);
  }

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

@media (max-width: 640px) {
  .menu-toggle {
    display: inline-flex;
    flex-direction: column;
  }

  .nav {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    padding-bottom: 8px;
  }

  .nav.open {
    display: flex;
  }

  .header-inner {
    flex-wrap: wrap;
  }

  .feature-grid,
  .shot-row,
  .shot-row.cols-3,
  .shot-row.cols-2 {
    grid-template-columns: 1fr 1fr;
    gap: 10px;
  }

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

  .section {
    padding: 40px 0;
  }

  .hero {
    padding: 28px 0 24px;
  }

  .download-box {
    padding: 22px 16px;
  }
}