:root {
  --bg: #0b0b0d;
  --bg-2: #141418;
  --bg-3: #1c1c22;
  --text: #f2f2f4;
  --muted: #a3a3ad;
  --line: #2a2a32;
  --accent: #e11d2e;
  --accent-2: #22c55e;
  --gold: #eab308;
  --max: 1120px;
  --radius: 10px;
  --nav-h: 56px;
  --header-offset: 56px;
  --font: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html { scroll-behavior: smooth; }

html, body {
  overflow-x: hidden;
}

body {
  font-family: var(--font);
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(225, 29, 46, 0.18), transparent 55%),
    radial-gradient(900px 420px at 90% 0%, rgba(34, 197, 94, 0.08), transparent 50%),
    linear-gradient(180deg, #101014 0%, var(--bg) 35%, #09090b 100%);
  color: var(--text);
  line-height: 1.75;
  min-height: 100vh;
  padding-top: var(--header-offset);
}

a { color: var(--accent-2); text-decoration: none; }
a:hover { color: #4ade80; text-decoration: underline; }

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

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

/* Header - always fixed */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(11, 11, 13, 0.96);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  height: var(--nav-h);
  min-height: var(--nav-h);
  padding: 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  text-decoration: none;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.04em;
}
.brand:hover { text-decoration: none; color: var(--text); }
.brand img {
  width: 40px;
  height: 40px;
  border-radius: 9px;
  object-fit: cover;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 14px;
  align-items: center;
}
.nav a {
  color: var(--muted);
  font-size: 0.95rem;
  text-decoration: none;
}
.nav a:hover,
.nav a.active { color: var(--text); }

.menu-toggle {
  display: none;
  background: var(--bg-3);
  border: 1px solid var(--line);
  color: var(--text);
  padding: 8px 12px;
  border-radius: 8px;
  cursor: pointer;
}

/* Hero */
.hero {
  padding: 48px 0 28px;
  border-bottom: 1px solid var(--line);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 36px;
  align-items: center;
}

.hero-copy h1 {
  font-size: clamp(1.7rem, 3.2vw, 2.55rem);
  line-height: 1.25;
  margin: 10px 0 16px;
  font-weight: 800;
}

.hero-copy .lead {
  color: var(--muted);
  font-size: 1.05rem;
  margin-bottom: 22px;
}

.eyebrow {
  display: inline-block;
  color: var(--gold);
  font-size: 0.88rem;
  letter-spacing: 0.08em;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 18px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 8px;
  font-weight: 700;
  border: 1px solid transparent;
  text-decoration: none !important;
  cursor: pointer;
  transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}
.btn:hover { transform: translateY(-1px); }

.btn-primary {
  background: linear-gradient(135deg, #e11d2e, #b91c1c);
  color: #fff !important;
}
.btn-primary:hover { background: linear-gradient(135deg, #f43f5e, #dc2626); }

.btn-secondary {
  background: transparent;
  border-color: var(--line);
  color: var(--text) !important;
}
.btn-secondary:hover { border-color: var(--accent-2); color: var(--accent-2) !important; }

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  color: var(--muted);
  font-size: 0.92rem;
}
.hero-meta span::before {
  content: "";
  display: inline-block;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent-2);
  margin-right: 8px;
  vertical-align: middle;
}

.hero-visual {
  position: relative;
}
.hero-visual img {
  width: 100%;
  border-radius: 14px;
  border: 1px solid var(--line);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.45);
}
.hero-visual::after {
  content: "";
  position: absolute;
  inset: auto -8% -10% 20%;
  height: 40%;
  background: radial-gradient(ellipse, rgba(225, 29, 46, 0.25), transparent 70%);
  z-index: -1;
  pointer-events: none;
}

/* Sections */
.section {
  padding: 56px 0;
  border-bottom: 1px solid var(--line);
}
.section-head {
  margin-bottom: 28px;
  max-width: 760px;
}
.section-head h2 {
  font-size: clamp(1.4rem, 2.4vw, 1.9rem);
  margin-bottom: 10px;
  line-height: 1.3;
}
.section-head p { color: var(--muted); }

.prose p {
  margin-bottom: 14px;
  color: #d4d4d8;
}
.prose h3 {
  font-size: 1.2rem;
  margin: 26px 0 10px;
  color: #fff;
}
.prose ul, .prose ol {
  margin: 10px 0 16px 1.2em;
  color: #d4d4d8;
}
.prose li { margin-bottom: 8px; }

.dual {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  align-items: start;
}
.shot {
  border-radius: var(--radius);
  border: 1px solid var(--line);
  overflow: hidden;
  background: var(--bg-2);
}
.shot img { width: 100%; }
.shot figcaption {
  padding: 12px 14px;
  color: var(--muted);
  font-size: 0.9rem;
  border-top: 1px solid var(--line);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.feature {
  background: linear-gradient(180deg, var(--bg-2), var(--bg-3));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}
.feature h3 {
  font-size: 1.05rem;
  margin-bottom: 8px;
}
.feature p {
  color: var(--muted);
  font-size: 0.95rem;
}

.gallery {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}
.gallery .shot { margin: 0; }

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  counter-reset: step;
}
.step {
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  position: relative;
}
.step::before {
  counter-increment: step;
  content: counter(step);
  display: inline-flex;
  width: 28px;
  height: 28px;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  font-size: 0.85rem;
  margin-bottom: 10px;
}
.step h3 { font-size: 1rem; margin-bottom: 6px; }
.step p { color: var(--muted); font-size: 0.92rem; }

.faq details {
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 16px;
  margin-bottom: 10px;
}
.faq summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq details[open] summary { color: var(--accent-2); margin-bottom: 8px; }
.faq p { color: var(--muted); }

.links-box {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 16px;
  padding: 18px;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.download-banner {
  background:
    linear-gradient(120deg, rgba(225, 29, 46, 0.22), rgba(34, 197, 94, 0.12)),
    var(--bg-2);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 28px;
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  align-items: center;
  justify-content: space-between;
}
.download-banner h2 { margin-bottom: 8px; }
.download-banner p { color: var(--muted); max-width: 620px; }

/* Legal / inner pages */
.page-hero {
  padding: 42px 0 18px;
  border-bottom: 1px solid var(--line);
}
.page-hero h1 {
  font-size: clamp(1.6rem, 2.8vw, 2.2rem);
  margin-bottom: 10px;
}
.page-hero p { color: var(--muted); }
.legal {
  padding: 36px 0 60px;
  max-width: 860px;
}
.legal h2 {
  font-size: 1.25rem;
  margin: 28px 0 10px;
}
.legal p, .legal li { color: #d4d4d8; margin-bottom: 12px; }
.legal ul { margin-left: 1.2em; }

/* Error pages */
.error-page {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 60px 16px;
}
.error-page .code {
  font-size: clamp(4rem, 12vw, 7rem);
  font-weight: 800;
  line-height: 1;
  background: linear-gradient(135deg, #e11d2e, #22c55e);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 10px;
}
.error-page h1 { margin-bottom: 12px; }
.error-page p { color: var(--muted); margin-bottom: 22px; }

/* Footer */
.site-footer {
  padding: 36px 0 28px;
  background: #08080a;
  border-top: 1px solid var(--line);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 24px;
  margin-bottom: 24px;
}
.site-footer h3 {
  font-size: 1rem;
  margin-bottom: 12px;
}
.site-footer p, .site-footer a {
  color: var(--muted);
  font-size: 0.92rem;
}
.site-footer a { display: block; margin-bottom: 8px; text-decoration: none; }
.site-footer a:hover { color: var(--accent-2); }
.copyright {
  border-top: 1px solid var(--line);
  padding-top: 16px;
  color: #71717a;
  font-size: 0.85rem;
  text-align: center;
}

@media (max-width: 960px) {
  .hero-grid,
  .dual,
  .footer-grid { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: 1fr 1fr; }
  .gallery { grid-template-columns: 1fr 1fr; }
  .steps { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 720px) {
  .header-inner {
    position: relative;
    flex-wrap: nowrap;
  }

  .menu-toggle {
    display: inline-flex;
    margin-left: auto;
    z-index: 2;
  }

  .nav {
    display: none;
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    width: 100%;
    margin: 0;
    padding: 10px 16px 14px;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: rgba(11, 11, 13, 0.98);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.35);
    z-index: 1001;
    max-height: calc(100vh - var(--nav-h));
    overflow-y: auto;
  }

  .nav.open { display: flex; }

  .nav a {
    display: block;
    padding: 12px 4px;
    border-bottom: 1px solid var(--line);
    font-size: 1rem;
  }

  .nav a:last-child { border-bottom: none; }

  .hero { padding: 28px 0 20px; }
  .section { padding: 40px 0; }
  .feature-grid,
  .gallery,
  .steps { grid-template-columns: 1fr; }
  .download-banner { padding: 22px; }
  .cta-row .btn { width: 100%; }
}