:root {
  --bg: #f7f8fa;
  --surface: #ffffff;
  --text: #1c2330;
  --muted: #5b6577;
  --border: #e3e6ec;
  --accent: #2f6fde;
  --accent-soft: #eaf1fd;
  --on-accent: #ffffff;
  --radius: 12px;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12151b;
    --surface: #1a1e26;
    --text: #e6e9ef;
    --muted: #9aa3b2;
    --border: #2a303b;
    --accent: #6b9cf0;
    --accent-soft: #1e2a40;
    --on-accent: #12151b;
    color-scheme: dark;
  }
}

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family:
    system-ui,
    -apple-system,
    'Segoe UI',
    Roboto,
    'Helvetica Neue',
    Arial,
    'PingFang SC',
    'Microsoft YaHei',
    sans-serif;
  font-size: 16px;
  line-height: 1.65;
}

a {
  color: var(--accent);
}

.wrap {
  max-width: 880px;
  margin: 0 auto;
  padding: 0 16px;
}

/* Header */
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}

.site-header .wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  min-height: 64px;
  padding-top: 10px;
  padding-bottom: 10px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.2px;
  text-decoration: none;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px 20px;
  font-size: 15px;
}

.site-nav a {
  color: var(--muted);
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a[aria-current='page'] {
  color: var(--accent);
}

/* Sign-in entry to the console (app.bxads.com) */
.site-nav .nav-signin,
.button {
  display: inline-block;
  background: var(--accent);
  color: var(--on-accent);
  font-weight: 600;
  text-decoration: none;
  border-radius: 999px;
}

.site-nav .nav-signin {
  padding: 4px 14px;
}

.site-nav .nav-signin:hover,
.button:hover {
  color: var(--on-accent);
  opacity: 0.9;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 16px;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.button {
  padding: 10px 22px;
  font-size: 16px;
}

/* Main */
main {
  padding: 48px 0 64px;
}

.hero h1 {
  margin: 0 0 12px;
  font-size: 40px;
  line-height: 1.2;
}

.lead {
  margin: 0;
  color: var(--muted);
  font-size: 18px;
}

section {
  margin-top: 48px;
}

h2 {
  margin: 0 0 16px;
  font-size: 22px;
  line-height: 1.35;
}

h3 {
  margin: 0 0 6px;
  font-size: 17px;
}

.features {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.card {
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

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

.note {
  padding: 20px;
  background: var(--accent-soft);
  border-radius: var(--radius);
}

.note p {
  margin: 0 0 10px;
}

.note p:last-child {
  margin-bottom: 0;
}

/* Legal pages */
.doc {
  padding: 32px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.doc h1 {
  margin: 0 0 4px;
  font-size: 32px;
  line-height: 1.25;
}

.doc .meta {
  margin: 0 0 24px;
  color: var(--muted);
}

.doc h2 {
  margin-top: 32px;
  font-size: 20px;
}

.doc ul {
  padding-left: 22px;
}

.doc li {
  margin-bottom: 6px;
}

/* Footer */
.site-footer {
  padding: 24px 0 40px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 14px;
}

.site-footer .wrap {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 16px;
}

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

@media (max-width: 640px) {
  main {
    padding: 32px 0 48px;
  }

  .hero h1 {
    font-size: 32px;
  }

  .lead {
    font-size: 17px;
  }

  section {
    margin-top: 36px;
  }

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

  .doc {
    padding: 20px 16px;
  }

  .doc h1 {
    font-size: 26px;
  }
}