/* algo: high-contrast indigo + amber */
body.theme-algo {
  --site-accent: #8fa6ff;
  --site-accent-soft: #6f86ef;
  --site-accent-ink: #eef1ff;
}

body.theme-algo .site-header {
  background: linear-gradient(90deg, rgba(14, 18, 43, 0.92), rgba(27, 21, 52, 0.84));
  border-bottom-color: rgba(145, 158, 239, 0.26);
}

body.theme-algo .brand-link {
  color: #eff3ff;
}

body.theme-algo .nav-link:hover,
body.theme-algo .nav-btn:hover {
  background: rgba(117, 133, 234, 0.18);
  text-decoration: none;
}

body.theme-algo .site-switcher-trigger {
  border-color: rgba(148, 162, 244, 0.36);
}

body.theme-algo .site-switcher-item.is-current {
  background: rgba(132, 148, 243, 0.24);
}

:root[data-theme='light'] body.theme-algo {
  --site-accent: #4a60cf;
  --site-accent-soft: #6075db;
  --site-accent-ink: #1b255f;
}

:root[data-theme='light'] body.theme-algo .site-header {
  background: linear-gradient(90deg, rgba(247, 248, 255, 0.95), rgba(239, 241, 255, 0.90));
  border-bottom-color: rgba(92, 109, 191, 0.26);
}

:root[data-theme='light'] body.theme-algo .brand-link {
  color: #19285f;
}