:root {
  --auth-bg: #0f172a;
  --auth-card: #ffffff;
  --auth-accent: #2563eb;
  --auth-muted: #64748b;
  --auth-border: #e2e8f0;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }

body.auth-body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: var(--auth-bg);
  color: #0f172a;
}

.auth-visual {
  padding: 48px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  color: #e2e8f0;
  background: linear-gradient(145deg, #1e3a8a 0%, #0f172a 55%, #172554 100%);
}

.auth-visual h1 {
  margin: 0 0 12px;
  font-size: clamp(28px, 4vw, 40px);
  line-height: 1.2;
}

.auth-visual p {
  margin: 0;
  color: #94a3b8;
  max-width: 420px;
  line-height: 1.7;
}

.auth-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 28px;
}

.auth-badge {
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(255,255,255,.08);
  border: 1px solid rgba(255,255,255,.12);
  font-size: 13px;
}

.auth-panel {
  display: grid;
  place-items: center;
  padding: 32px;
  background: #f8fafc;
}

.auth-card {
  width: min(420px, 100%);
  background: var(--auth-card);
  border-radius: 20px;
  padding: 36px;
  box-shadow: 0 24px 60px rgba(15, 23, 42, 0.12);
  border: 1px solid var(--auth-border);
}

.auth-card h2 {
  margin: 0 0 8px;
  font-size: 24px;
}

.auth-card .muted {
  color: var(--auth-muted);
  font-size: 14px;
  margin: 0 0 24px;
}

.auth-form label {
  display: grid;
  gap: 8px;
  font-size: 14px;
  color: #334155;
  margin-bottom: 16px;
}

.auth-form input {
  padding: 12px 14px;
  border: 1px solid var(--auth-border);
  border-radius: 12px;
  font: inherit;
}

.auth-form input:focus {
  outline: 2px solid rgba(37, 99, 235, 0.25);
  border-color: var(--auth-accent);
}

.auth-btn {
  width: 100%;
  padding: 12px 16px;
  border: none;
  border-radius: 12px;
  background: var(--auth-accent);
  color: #fff;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  margin-top: 8px;
}

.auth-btn:hover { filter: brightness(1.05); }

.alert {
  padding: 12px 14px;
  border-radius: 10px;
  margin-bottom: 16px;
  font-size: 14px;
}
.alert-error { background: #fef2f2; color: #dc2626; }
.alert-success { background: #ecfdf5; color: #059669; }

@media (max-width: 900px) {
  body.auth-body { grid-template-columns: 1fr; }
  .auth-visual { padding: 32px 24px; min-height: auto; }
  .auth-panel { padding: 24px; }
}