:root {
  --bg: #f7f8fc;
  --bg-elev: #ffffff;
  --text: #141a2e;
  --text-muted: #5b6480;
  --border: #e3e6f0;
  --accent: #4f5bd5;
  --accent-strong: #3b45b8;
  --accent-soft: #eceefe;
  --glow: rgba(255, 196, 92, 0.55);
  --radius: 16px;
  --max: 1080px;
  font-family:
    -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB',
    'Microsoft YaHei', 'Noto Sans SC', Roboto, Helvetica, Arial, sans-serif;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1020;
    --bg-elev: #151a30;
    --text: #eef0fa;
    --text-muted: #a3aac4;
    --border: #262c47;
    --accent: #8b93ff;
    --accent-strong: #a9afff;
    --accent-soft: #1d2242;
    --glow: rgba(255, 196, 92, 0.35);
    color-scheme: dark;
  }
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  color: var(--accent-strong);
  text-decoration: underline;
}

.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 20px;
  color: var(--text);
  letter-spacing: -0.01em;
}

.brand:hover {
  color: var(--text);
  text-decoration: none;
}

.brand img {
  width: 30px;
  height: 30px;
}

.lang-switch {
  display: inline-flex;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 3px;
  background: var(--bg-elev);
}

.lang-switch button {
  border: 0;
  background: transparent;
  color: var(--text-muted);
  font: inherit;
  font-size: 14px;
  padding: 4px 12px;
  border-radius: 999px;
  cursor: pointer;
}

.lang-switch button[aria-pressed='true'] {
  background: var(--accent);
  color: #fff;
}

/* Hero */
.hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding: 88px 0 72px;
  text-align: center;
}

.hero::before {
  content: '';
  position: absolute;
  inset: -40% 20% auto;
  height: 520px;
  background: radial-gradient(closest-side, var(--glow), transparent 70%);
  filter: blur(20px);
  z-index: -1;
}

.badge {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 20px;
}

.hero h1 {
  font-size: clamp(34px, 6vw, 56px);
  line-height: 1.15;
  margin: 0 0 18px;
  letter-spacing: -0.02em;
}

.hero p.lead {
  font-size: clamp(17px, 2.2vw, 20px);
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 auto 32px;
}

.cta-row {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 12px 22px;
  border-radius: 12px;
  font-weight: 600;
  font-size: 16px;
  border: 1px solid transparent;
}

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

.btn-primary:hover {
  background: var(--accent-strong);
  color: #fff;
  text-decoration: none;
}

.btn-ghost {
  border-color: var(--border);
  color: var(--text);
  background: var(--bg-elev);
}

.btn-ghost:hover {
  color: var(--text);
  text-decoration: none;
  border-color: var(--accent);
}

/* Sections */
section {
  padding: 64px 0;
}

.section-title {
  text-align: center;
  font-size: clamp(26px, 4vw, 34px);
  margin: 0 0 12px;
  letter-spacing: -0.01em;
}

.section-sub {
  text-align: center;
  color: var(--text-muted);
  margin: 0 auto 40px;
  max-width: 600px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 18px;
}

.card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}

.card .icon {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  background: var(--accent-soft);
  color: var(--accent);
  display: grid;
  place-items: center;
  margin-bottom: 14px;
}

.card h3 {
  margin: 0 0 8px;
  font-size: 18px;
}

.card p {
  margin: 0;
  color: var(--text-muted);
  font-size: 15px;
}

/* Steps */
.steps {
  counter-reset: step;
}

.steps .card {
  position: relative;
  padding-top: 56px;
}

.steps .card::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  top: 20px;
  left: 24px;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  font-size: 14px;
  display: grid;
  place-items: center;
}

/* Clients */
.clients {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.client {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 10px 18px;
  font-weight: 600;
  font-size: 15px;
}

.client small {
  color: var(--text-muted);
  font-weight: 400;
  margin-left: 6px;
}

/* Contact */
.contact {
  text-align: center;
}

.contact .card {
  max-width: 560px;
  margin: 0 auto;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 28px 0 40px;
  color: var(--text-muted);
  font-size: 14px;
}

.site-footer .wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
  justify-content: space-between;
}

.site-footer nav {
  display: flex;
  gap: 20px;
}

/* Legal page */
.legal {
  padding-top: 48px;
  padding-bottom: 72px;
  max-width: 760px;
}

.legal h1 {
  font-size: 32px;
  margin: 0 0 8px;
}

.legal h2 {
  font-size: 22px;
  margin: 40px 0 8px;
}

.legal .note {
  background: var(--accent-soft);
  border-radius: 12px;
  padding: 14px 18px;
  color: var(--text);
  font-size: 15px;
}

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

/* Language visibility */
[data-lang-block] {
  display: none;
}

html[lang='en'] [data-lang-block='en'],
html[lang='zh-CN'] [data-lang-block='zh-CN'] {
  display: revert;
}

@media (max-width: 480px) {
  .hero {
    padding: 64px 0 48px;
  }

  section {
    padding: 48px 0;
  }

  .site-footer .wrap {
    flex-direction: column;
  }
}