:root {
  --bg: #0a0a0c;
  --bg-soft: #141418;
  --bg-card: #1a1a20;
  --text: #f5f5f7;
  --text-muted: #a0a0ab;
  --accent: #ff4d6d;
  --accent-2: #ff8a3d;
  --grad: linear-gradient(135deg, #ff8a3d 0%, #ff4d6d 55%, #c43bff 100%);
  --line: rgba(255, 255, 255, 0.08);
  --radius: 14px;
  --shadow: 0 18px 40px rgba(0, 0, 0, 0.35);
  --max: 1120px;
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(255, 138, 61, 0.18), transparent 60%),
    radial-gradient(900px 420px at 90% 0%, rgba(196, 59, 255, 0.14), transparent 55%),
    var(--bg);
  color: var(--text);
  line-height: 1.75;
  min-height: 100vh;
}

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

a {
  color: #ffb4c0;
  text-decoration: none;
  transition: color 0.2s ease, opacity 0.2s ease;
}

a:hover {
  color: #fff;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  background: rgba(10, 10, 12, 0.82);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 0;
}

.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: 10px;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 14px;
  align-items: center;
}

.nav a {
  color: var(--text-muted);
  font-size: 0.95rem;
  padding: 6px 0;
}

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

.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--line);
  background: var(--bg-soft);
  color: var(--text);
  border-radius: 10px;
  padding: 0;
  cursor: pointer;
}

.menu-toggle svg {
  width: 22px;
  height: 22px;
  display: block;
}

.hero {
  padding: 48px 0 28px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 28px;
  align-items: center;
}

.eyebrow {
  display: inline-block;
  font-size: 0.85rem;
  color: #ffd0b5;
  background: rgba(255, 138, 61, 0.12);
  border: 1px solid rgba(255, 138, 61, 0.28);
  border-radius: 999px;
  padding: 4px 12px;
  margin-bottom: 14px;
}

.hero h1 {
  font-size: clamp(1.8rem, 3.4vw, 2.6rem);
  line-height: 1.25;
  margin-bottom: 14px;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

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

.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 20px;
  border-radius: 999px;
  font-weight: 600;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--grad);
  color: #fff;
  box-shadow: 0 10px 28px rgba(255, 77, 109, 0.28);
}

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

.btn-ghost {
  background: rgba(255, 255, 255, 0.04);
  border-color: var(--line);
  color: var(--text);
}

.hero-visual {
  position: relative;
  border-radius: 22px;
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid var(--line);
  background: #000;
}

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

.hero-badge {
  position: absolute;
  left: 14px;
  bottom: 14px;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(8px);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px 12px;
  font-size: 0.85rem;
}

section {
  padding: 42px 0;
}

.section-head {
  margin-bottom: 22px;
}

.section-head h2 {
  font-size: clamp(1.35rem, 2.4vw, 1.85rem);
  margin-bottom: 8px;
}

.section-head p {
  color: var(--text-muted);
  max-width: 720px;
}

.grid-3,
.grid-4,
.grid-2 {
  display: grid;
  gap: 16px;
}

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

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

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

.card {
  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);
  overflow: hidden;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.card:hover {
  transform: translateY(-3px);
  border-color: rgba(255, 77, 109, 0.35);
}

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

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

.card-body h3 {
  font-size: 1.02rem;
  margin-bottom: 6px;
}

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

.feature-list {
  display: grid;
  gap: 14px;
}

.feature-item {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 16px;
  align-items: start;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px;
}

.feature-item img {
  width: 120px;
  border-radius: 10px;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
}

.prose {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 28px 24px;
}

.prose h2,
.prose h3 {
  margin: 1.4em 0 0.55em;
}

.prose h2:first-child,
.prose h3:first-child {
  margin-top: 0;
}

.prose p {
  margin-bottom: 1em;
  color: #d7d7df;
}

.prose ul,
.prose ol {
  margin: 0 0 1em 1.2em;
  color: #d7d7df;
}

.prose li {
  margin-bottom: 0.45em;
}

.breadcrumb {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin: 18px 0 8px;
}

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

.page-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 10px;
}

.page-desc {
  color: var(--text-muted);
  margin-bottom: 22px;
}

.toc {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 18px 0 8px;
}

.toc a {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 6px 12px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.internal-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 18px;
}

.internal-links a {
  display: block;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px;
  color: var(--text);
}

.internal-links a span {
  display: block;
  color: var(--text-muted);
  font-size: 0.88rem;
  margin-top: 4px;
}

.site-footer {
  margin-top: 40px;
  border-top: 1px solid var(--line);
  background: #08080a;
  padding: 34px 0 24px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 24px;
  margin-bottom: 22px;
}

.site-footer h3 {
  font-size: 1rem;
  margin-bottom: 10px;
}

.site-footer p,
.site-footer a {
  color: var(--text-muted);
  font-size: 0.92rem;
}

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

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

.copyright {
  border-top: 1px solid var(--line);
  padding-top: 16px;
  color: #777784;
  font-size: 0.85rem;
}

.error-wrap {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 60px 16px;
}

.error-wrap h1 {
  font-size: clamp(2.4rem, 8vw, 4.5rem);
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 10px;
}

.error-wrap p {
  color: var(--text-muted);
  margin-bottom: 22px;
}

@media (max-width: 960px) {
  .hero-grid,
  .grid-3,
  .grid-4,
  .footer-grid,
  .internal-links {
    grid-template-columns: 1fr 1fr;
  }

  .feature-item {
    grid-template-columns: 96px 1fr;
  }

  .feature-item img {
    width: 96px;
  }
}

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

  .nav {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: flex-start;
    padding-bottom: 10px;
  }

  .nav.open {
    display: flex;
  }

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

  .hero-grid,
  .grid-2,
  .grid-3,
  .grid-4,
  .footer-grid,
  .internal-links {
    grid-template-columns: 1fr;
  }

  .hero {
    padding-top: 28px;
  }

  .hero-visual img {
    max-height: 420px;
  }

  .prose {
    padding: 20px 16px;
  }

  section {
    padding: 30px 0;
  }
}