* { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #F8FAFC;
  --card: #FFFFFF;
  --text: #0F172A;
  --muted: #64748B;
  --line: #E2E8F0;
  --accent: #2563EB;
  --accent-2: #4F46E5;
  --danger: #DC2626;
}

html, body { height: 100%; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, "PingFang SC", "Microsoft YaHei", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  -webkit-font-smoothing: antialiased;
}

.gate { width: 100%; max-width: 420px; }

.gate-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 40px 36px 36px;
  box-shadow: 0 8px 30px rgba(15, 23, 42, 0.06);
}

.gate-brand { display: flex; align-items: center; gap: 10px; }
.gate-brand img { height: 34px; width: auto; display: block; }

.gate-tag { margin-top: 10px; font-size: 12px; color: var(--muted); }

.gate-card h1 { margin-top: 26px; font-size: 24px; font-weight: 700; letter-spacing: -0.02em; }

.gate-desc {
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

#gate-form { margin-top: 26px; }

.gate-label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 8px; }

#gate-password {
  width: 100%;
  height: 46px;
  padding: 0 14px;
  font-size: 15px;
  color: var(--text);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  outline: none;
  transition: border-color 0.15s, box-shadow 0.15s;
}

#gate-password:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.14);
}

#gate-submit {
  width: 100%;
  height: 46px;
  margin-top: 14px;
  border: none;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: opacity 0.15s;
}

#gate-submit:hover { opacity: 0.92; }
#gate-submit:active { opacity: 0.85; }
#gate-submit:disabled { opacity: 0.6; cursor: default; }

.gate-error {
  margin-top: 12px;
  font-size: 13px;
  color: var(--danger);
}

.gate-foot { margin-top: 22px; text-align: center; font-size: 12px; color: var(--muted); }

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}