:root {
  --ds-blue: #4d6bfe;
  --ds-blue-hover: #3f5be8;
  --ds-text: #1b1f2a;
  --ds-muted: #8b8fa3;
  --ds-line: #e5e7ef;
  --font: "Inter", "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
}

* { box-sizing: border-box; }

html, body { height: 100%; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ds-text);
  background: #ffffff;
  background-image: radial-gradient(900px 480px at 50% -12%, rgba(77, 107, 254, 0.08), transparent 62%);
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; }

.lg-topbar {
  position: fixed; top: 0; left: 0; right: 0;
  display: flex; align-items: center; justify-content: space-between;
  padding: 22px 34px;
}

.lg-brand { display: inline-flex; align-items: center; gap: 10px; }
.lg-logo {
  width: 32px; height: 32px; border-radius: 9px;
  display: grid; place-items: center;
  background: linear-gradient(135deg, var(--ds-blue), #7c93ff);
  color: #fff; font-size: 12px; font-weight: 800;
  box-shadow: 0 6px 14px rgba(77, 107, 254, 0.28);
}
.lg-brand-name { font-size: 15px; font-weight: 700; color: #141824; letter-spacing: 0.4px; }
.lg-back { font-size: 12.5px; color: var(--ds-muted); }
.lg-back:hover { color: var(--ds-blue); }

.lg-main {
  min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  padding: 88px 20px 64px;
}

.lg-card {
  width: 100%; max-width: 400px;
  background: #ffffff;
  border: 1px solid #eceef5;
  border-radius: 20px;
  padding: 34px 32px 26px;
  box-shadow: 0 20px 50px rgba(27, 31, 42, 0.07);
}

.lg-title { margin: 0; font-size: 26px; font-weight: 700; letter-spacing: 0.3px; color: #141824; }
.lg-sub { margin: 9px 0 26px; font-size: 13px; color: var(--ds-muted); }

.lg-form { display: flex; flex-direction: column; gap: 16px; }
.lg-field { display: flex; flex-direction: column; gap: 7px; }
.lg-label { font-size: 12px; color: #6b7280; }

.lg-input {
  width: 100%; height: 46px;
  padding: 0 14px;
  border: 1px solid var(--ds-line);
  border-radius: 12px;
  background: #ffffff;
  color: var(--ds-text);
  font-family: inherit; font-size: 14px;
  outline: none;
  transition: 0.18s;
}
.lg-input::placeholder { color: #a9adbd; }
.lg-input:focus {
  border-color: var(--ds-blue);
  box-shadow: 0 0 0 3px rgba(77, 107, 254, 0.13);
}

.lg-btn {
  height: 46px; margin-top: 4px;
  border: none; border-radius: 12px;
  background: var(--ds-blue);
  color: #fff;
  font-family: inherit; font-size: 14px; font-weight: 600;
  cursor: pointer;
  transition: 0.18s;
}
.lg-btn:hover:not(:disabled) { background: var(--ds-blue-hover); }
.lg-btn:disabled { opacity: 0.6; cursor: not-allowed; }

.lg-error {
  padding: 9px 12px;
  border-radius: 9px;
  background: #fef2f2;
  border: 1px solid #f6cccc;
  color: #d93025;
  font-size: 12px;
  line-height: 1.5;
}

.lg-hint {
  display: flex; align-items: center; justify-content: space-between;
  gap: 10px; margin-top: 20px;
  font-size: 12px; color: #9aa0b0;
}
.lg-hint a { color: var(--ds-blue); }
.lg-hint a:hover { text-decoration: underline; }

.lg-footer {
  position: fixed; bottom: 20px; left: 0; right: 0;
  text-align: center;
  font-size: 11px; color: #b3b8c6;
}

.hidden { display: none !important; }

@media (max-width: 520px) {
  .lg-topbar { padding: 16px 18px; }
  .lg-card { padding: 28px 22px 22px; border-radius: 16px; }
  .lg-main { padding: 70px 16px 60px; align-items: flex-start; }
  .lg-title { font-size: 23px; }
}