:root {
  --bg: #0b0b0d;
  --bg-elevated: #141418;
  --bg-soft: #1a1a20;
  --line: #2c2c34;
  --text: #f2f2f4;
  --muted: #a0a0ab;
  --red: #c62828;
  --red-hot: #e53935;
  --green: #7ae582;
  --radius: 12px;
  --max: 1120px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.45);
  --font-display: "Syne", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(198, 40, 40, 0.18), transparent 55%),
    radial-gradient(900px 500px at 90% 0%, rgba(122, 229, 130, 0.08), transparent 50%),
    linear-gradient(180deg, #101014 0%, var(--bg) 40%, #09090b 100%);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  min-height: 100vh;
}

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

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

a:hover {
  color: #a8f5ae;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  background: rgba(11, 11, 13, 0.86);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 68px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: 0.02em;
}

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  object-fit: cover;
}

.brand span {
  font-size: 1.15rem;
}

.nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav a {
  color: var(--muted);
  padding: 8px 12px;
  border-radius: 999px;
  font-size: 0.95rem;
}

.nav a:hover,
.nav a.active {
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
}

.nav-cta {
  margin-left: 6px;
  background: linear-gradient(135deg, var(--red), #8e0000) !important;
  color: #fff !important;
  padding: 9px 16px !important;
}

.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background:
    linear-gradient(currentColor, currentColor) center / 18px 2px no-repeat,
    linear-gradient(currentColor, currentColor) center / 18px 2px no-repeat,
    linear-gradient(currentColor, currentColor) center / 18px 2px no-repeat,
    var(--bg-elevated);
  background-position:
    center calc(50% - 6px),
    center,
    center calc(50% + 6px),
    0 0;
  color: var(--text);
  cursor: pointer;
  padding: 0;
}

.hero {
  padding: 56px 0 28px;
}

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

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--green);
  font-size: 0.9rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

.hero h1 {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 3.2rem);
  line-height: 1.15;
  letter-spacing: 0.01em;
}

.hero-lead {
  color: var(--muted);
  font-size: 1.05rem;
  max-width: 38em;
  margin: 0 0 24px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 22px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 48px;
  padding: 0 22px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 600;
  cursor: pointer;
}

.btn-primary {
  background: linear-gradient(135deg, var(--red-hot), var(--red));
  color: #fff;
  box-shadow: 0 10px 28px rgba(198, 40, 40, 0.35);
}

.btn-primary:hover {
  color: #fff;
  opacity: 0.92;
}

.btn-secondary {
  background: transparent;
  border-color: var(--line);
  color: var(--text);
}

.btn-secondary:hover {
  border-color: rgba(255, 255, 255, 0.28);
  color: #fff;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 24px;
  color: var(--muted);
  font-size: 0.92rem;
}

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

.hero-visual {
  position: relative;
}

.phone-frame {
  border-radius: 28px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: var(--shadow);
  background: #000;
  transform: rotate(1.5deg);
}

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

.float-card {
  position: absolute;
  left: -18px;
  bottom: 34px;
  width: min(220px, 58%);
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: var(--shadow);
  transform: rotate(-6deg);
}

.section {
  padding: 56px 0;
}

.section-head {
  margin-bottom: 28px;
}

.section-head h2 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  line-height: 1.25;
}

.section-head p {
  margin: 0;
  color: var(--muted);
  max-width: 48em;
}

.feature-grid,
.shot-grid,
.card-grid {
  display: grid;
  gap: 18px;
}

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

.feature-card,
.content-card,
.shot-card,
.faq-item,
.prose,
.error-box {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.03), rgba(255, 255, 255, 0.015));
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.feature-card {
  padding: 22px;
}

.feature-card h3,
.content-card h3,
.shot-card h3 {
  margin: 0 0 10px;
  font-size: 1.15rem;
  font-family: var(--font-display);
}

.feature-card p,
.content-card p,
.shot-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.96rem;
}

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

.shot-card {
  overflow: hidden;
}

.shot-card img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  border-bottom: 1px solid var(--line);
}

.shot-card .shot-body {
  padding: 14px 14px 16px;
}

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

.content-card {
  padding: 24px;
}

.content-card img {
  width: 100%;
  border-radius: 10px;
  margin-bottom: 14px;
  border: 1px solid var(--line);
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  max-height: 420px;
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  align-items: center;
}

.split-media {
  border-radius: 18px;
  overflow: hidden;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.split-media img {
  width: 100%;
  aspect-ratio: 9 / 16;
  max-height: 560px;
  object-fit: cover;
  object-position: top;
}

.split-copy h2 {
  margin-top: 0;
  font-family: var(--font-display);
}

.split-copy p {
  color: var(--muted);
}

.split-copy ul {
  margin: 0;
  padding-left: 1.15em;
  color: var(--muted);
}

.split-copy li + li {
  margin-top: 8px;
}

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

.step {
  padding: 18px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--bg-elevated);
}

.step-num {
  display: inline-flex;
  width: 28px;
  height: 28px;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: rgba(198, 40, 40, 0.2);
  color: #ff8a80;
  font-size: 0.85rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.step h3 {
  margin: 0 0 8px;
  font-size: 1rem;
}

.step p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.prose {
  padding: 28px;
}

.prose h2,
.prose h3 {
  font-family: var(--font-display);
  line-height: 1.35;
}

.prose h2 {
  margin-top: 1.6em;
  margin-bottom: 0.6em;
  font-size: 1.45rem;
}

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

.prose h3 {
  margin-top: 1.35em;
  margin-bottom: 0.45em;
  font-size: 1.15rem;
}

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

.prose p {
  margin: 0 0 1em;
}

.prose ul,
.prose ol {
  padding-left: 1.2em;
  margin: 0 0 1em;
}

.prose li + li {
  margin-top: 0.45em;
}

.toc {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px 18px;
  margin: 0 0 24px;
  padding: 18px;
  border-radius: 12px;
  background: var(--bg-soft);
  border: 1px solid var(--line);
}

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

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

.faq-item {
  padding: 18px 20px;
}

.faq-item h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
}

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

.cta-banner {
  padding: 34px;
  border-radius: 18px;
  border: 1px solid rgba(198, 40, 40, 0.35);
  background:
    radial-gradient(600px 180px at 0% 0%, rgba(198, 40, 40, 0.28), transparent 60%),
    linear-gradient(135deg, #1a1012, #121218);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  flex-wrap: wrap;
}

.cta-banner h2 {
  margin: 0 0 8px;
  font-family: var(--font-display);
}

.cta-banner p {
  margin: 0;
  color: var(--muted);
}

.page-hero {
  padding: 42px 0 10px;
}

.page-hero h1 {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 3.4vw, 2.6rem);
}

.page-hero p {
  margin: 0;
  color: var(--muted);
  max-width: 46em;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 14px;
}

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

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

.site-footer {
  margin-top: 40px;
  border-top: 1px solid var(--line);
  background: #09090b;
  padding: 36px 0 28px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 24px;
  margin-bottom: 24px;
}

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

.footer-brand img {
  width: 48px;
  height: 48px;
  border-radius: 12px;
}

.footer-brand p,
.footer-col p,
.footer-bottom {
  color: var(--muted);
  font-size: 0.92rem;
}

.footer-col h3 {
  margin: 0 0 12px;
  font-size: 1rem;
}

.footer-col a {
  display: block;
  color: var(--muted);
  margin-bottom: 8px;
}

.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 18px;
  justify-content: space-between;
}

.error-wrap {
  min-height: 70vh;
  display: grid;
  place-items: center;
  padding: 40px 0;
}

.error-box {
  width: min(100%, 640px);
  padding: 36px 28px;
  text-align: center;
}

.error-box .code {
  font-family: var(--font-display);
  font-size: 4rem;
  line-height: 1;
  color: var(--red-hot);
  margin-bottom: 8px;
}

.error-box h1 {
  margin: 0 0 12px;
  font-family: var(--font-display);
}

.error-box p {
  color: var(--muted);
  margin: 0 0 22px;
}

.age-note {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(198, 40, 40, 0.15);
  color: #ffab91;
  font-size: 0.85rem;
  border: 1px solid rgba(198, 40, 40, 0.35);
}

@media (max-width: 960px) {
  .hero-grid,
  .split,
  .footer-grid,
  .card-grid {
    grid-template-columns: 1fr;
  }

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

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

  .float-card {
    left: 12px;
    bottom: 18px;
  }

  .phone-frame {
    transform: none;
    max-width: 420px;
    margin-inline: auto;
  }
}

@media (max-width: 720px) {
  .menu-toggle {
    display: inline-block;
  }

  .nav {
    display: none;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 12px 16px 16px;
    background: rgba(12, 12, 14, 0.98);
    border-bottom: 1px solid var(--line);
  }

  .nav.open {
    display: flex;
  }

  .nav a {
    padding: 12px 14px;
  }

  .nav-cta {
    margin-left: 0;
    text-align: center;
  }

  .hero {
    padding-top: 28px;
  }

  .feature-grid,
  .steps,
  .shot-grid,
  .toc,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 40px 0;
  }

  .prose,
  .cta-banner {
    padding: 20px;
  }

  .hero-actions,
  .cta-banner {
    flex-direction: column;
    align-items: stretch;
  }

  .btn {
    width: 100%;
  }
}