:root {
  --bg: #0b1220;
  --card: rgba(255, 255, 255, 0.06);
  --border: rgba(255, 255, 255, 0.12);
  --text: rgba(255, 255, 255, 0.92);
  --muted: rgba(255, 255, 255, 0.68);
  --warn: #ffd36a;
}
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: radial-gradient(1200px 800px at 20% 10%, rgba(90,140,255,.28), transparent 60%),
              radial-gradient(1000px 700px at 85% 30%, rgba(255,120,210,.20), transparent 55%),
              radial-gradient(900px 650px at 40% 90%, rgba(60,255,200,.18), transparent 60%),
              var(--bg);
  color: var(--text);
}
.wrap { min-height: 100%; display: grid; place-items: center; padding: 24px; }
.card {
  width: min(520px, 92vw);
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 22px 20px 18px;
  backdrop-filter: blur(12px);
  box-shadow: 0 18px 60px rgba(0,0,0,.35);
}
.title { font-size: 18px; font-weight: 700; letter-spacing: .2px; }
.sub { margin-top: 10px; font-size: 13px; line-height: 1.6; color: var(--muted); }
.warn { margin-top: 12px; font-size: 13px; color: var(--warn); }
.spinner {
  margin-top: 16px;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 3px solid rgba(255, 255, 255, 0.18);
  border-top-color: rgba(255, 255, 255, 0.86);
  animation: spin 0.9s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }