:root {
  --bg: #0b0612;
  --bg-2: #140a1f;
  --panel: #1a1028;
  --line: rgba(255, 255, 255, 0.08);
  --text: #f4eef8;
  --muted: #b7a8c8;
  --pink: #ff3385;
  --pink-2: #ff6b9d;
  --orange: #ff7f6a;
  --accent: #a855f7;
  --max: 1120px;
  --radius: 14px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
  --font: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(255, 51, 133, 0.22), transparent 60%),
    radial-gradient(900px 500px at 90% 0%, rgba(168, 85, 247, 0.18), transparent 55%),
    linear-gradient(180deg, #120818 0%, var(--bg) 40%, #08040d 100%);
  line-height: 1.75;
  min-height: 100vh;
}

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

a {
  color: var(--pink-2);
  text-decoration: none;
}

a:hover {
  color: #fff;
}

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

.skip {
  position: absolute;
  left: -9999px;
}

.skip:focus {
  left: 16px;
  top: 16px;
  z-index: 1000;
  background: #fff;
  color: #000;
  padding: 8px 12px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  background: rgba(11, 6, 18, 0.82);
  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: 10px;
  color: #fff;
  font-weight: 700;
  letter-spacing: 0.02em;
}

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

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  align-items: center;
}

.nav a {
  color: var(--muted);
  font-size: 14px;
}

.nav a:hover,
.nav a.active {
  color: #fff;
}

.menu-btn {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--line);
  background: var(--panel);
  color: #fff;
  border-radius: 10px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
}

.menu-btn span {
  display: block;
  width: 18px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.menu-btn[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-btn[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.menu-btn[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 999px;
  border: 0;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  color: #fff;
  background: linear-gradient(135deg, var(--pink), var(--orange));
  box-shadow: 0 10px 30px rgba(255, 51, 133, 0.35);
}

.btn-ghost {
  color: #fff;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

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

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 36px;
  align-items: center;
}

.hero h1 {
  margin: 0 0 14px;
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1.25;
  background: linear-gradient(90deg, #fff, var(--pink-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero .lead {
  color: var(--muted);
  font-size: 17px;
  margin: 0 0 22px;
}

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

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  color: var(--muted);
  font-size: 13px;
}

.hero-meta span {
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.03);
  padding: 6px 10px;
  border-radius: 999px;
}

.phone-frame {
  position: relative;
  border-radius: 28px;
  padding: 12px;
  background: linear-gradient(160deg, rgba(255, 51, 133, 0.45), rgba(168, 85, 247, 0.25));
  box-shadow: var(--shadow);
}

.phone-frame img {
  border-radius: 20px;
  width: 100%;
}

.section {
  padding: 42px 0;
}

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

.section-head h2 {
  margin: 0 0 8px;
  font-size: clamp(22px, 3vw, 30px);
}

.section-head p {
  margin: 0;
  color: var(--muted);
  max-width: 760px;
}

.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

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

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

.card {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.04), rgba(255, 255, 255, 0.02));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.card img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  background: #000;
}

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

.card-body h3 {
  margin: 0 0 8px;
  font-size: 17px;
}

.card-body p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.feature {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 24px;
  align-items: center;
  padding: 22px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin-bottom: 18px;
}

.feature.reverse {
  grid-template-columns: 1.1fr 0.9fr;
}

.feature.reverse .feature-media {
  order: 2;
}

.feature-media img {
  border-radius: 12px;
  width: 100%;
  max-height: 520px;
  object-fit: cover;
  object-position: top;
}

.feature h3 {
  margin-top: 0;
}

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

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

.prose h2,
.prose h3 {
  color: #fff;
}

.prose h2 {
  margin-top: 1.6em;
}

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

.prose ul,
.prose ol {
  color: var(--muted);
  padding-left: 1.2em;
}

.prose li {
  margin: 0.4em 0;
}

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

.toc a {
  font-size: 13px;
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid var(--line);
  color: var(--muted);
  background: rgba(0, 0, 0, 0.2);
}

.steps {
  counter-reset: step;
  display: grid;
  gap: 14px;
}

.step {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 14px;
  align-items: start;
  padding: 16px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.03);
}

.step::before {
  counter-increment: step;
  content: counter(step);
  width: 48px;
  height: 48px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-weight: 700;
  background: linear-gradient(135deg, var(--pink), var(--accent));
}

.cta-band {
  margin: 20px 0 10px;
  padding: 28px;
  border-radius: 18px;
  background:
    linear-gradient(120deg, rgba(255, 51, 133, 0.25), rgba(168, 85, 247, 0.18)),
    var(--panel);
  border: 1px solid rgba(255, 51, 133, 0.25);
  text-align: center;
}

.cta-band h2 {
  margin: 0 0 10px;
}

.cta-band p {
  margin: 0 0 18px;
  color: var(--muted);
}

.site-footer {
  margin-top: 40px;
  border-top: 1px solid var(--line);
  background: rgba(0, 0, 0, 0.28);
  padding: 34px 0 24px;
}

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

.site-footer h3 {
  margin: 0 0 12px;
  font-size: 16px;
}

.site-footer p,
.site-footer a {
  color: var(--muted);
  font-size: 14px;
}

.site-footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-footer li {
  margin: 8px 0;
}

.copyright {
  margin-top: 24px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  color: #8d7c9d;
  font-size: 13px;
  text-align: center;
}

.page-hero {
  padding: 36px 0 10px;
}

.page-hero h1 {
  margin: 0 0 10px;
  font-size: clamp(26px, 3.5vw, 36px);
}

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

.breadcrumb {
  color: var(--muted);
  font-size: 13px;
  margin-bottom: 12px;
}

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

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

.error-page h1 {
  font-size: clamp(42px, 10vw, 88px);
  margin: 0;
  background: linear-gradient(135deg, var(--pink), var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.error-page p {
  color: var(--muted);
  max-width: 520px;
  margin: 12px auto 22px;
}

.keyword-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.keyword-cloud span {
  font-size: 12px;
  color: var(--muted);
  border: 1px dashed rgba(255, 255, 255, 0.12);
  padding: 4px 10px;
  border-radius: 999px;
}

@media (max-width: 960px) {
  .hero-grid,
  .feature,
  .feature.reverse,
  .grid-2,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .feature.reverse .feature-media {
    order: 0;
  }

  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr 1fr;
  }
}

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

  .nav {
    display: none;
    position: absolute;
    left: 16px;
    right: 16px;
    top: 64px;
    flex-direction: column;
    align-items: stretch;
    padding: 12px;
    background: #160d22;
    border: 1px solid var(--line);
    border-radius: 12px;
  }

  .nav.open {
    display: flex;
  }

  .hero {
    padding-top: 28px;
  }

  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }

  .card img,
  .feature-media img {
    max-height: 420px;
  }
}