/* ========== 登录页 ========== */
body {
  background: var(--bg-page);
  background-image: var(--grad-mesh);
  background-attachment: fixed;
  min-height: 100vh;
}

.login-wrap {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.login-card {
  width: 100%;
  max-width: 440px;
  background: var(--bg-surface);
  border-radius: var(--r-lg);
  border: 1px solid var(--border-default);
  box-shadow: var(--shadow-xl);
  padding: 40px 38px 32px;
  position: relative;
  overflow: hidden;
}
.login-card::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--grad-brand);
}

.login-header {
  text-align: center;
  margin-bottom: 32px;
}
.login-header .logo-mark {
  width: 48px; height: 48px; font-size: 22px;
  margin: 0 auto 14px;
  display: flex;
}
.login-header h1 {
  font-family: var(--font-display);
  font-size: 22px;
  margin: 0;
  font-weight: 700;
  letter-spacing: -0.015em;
}
.login-header .sub {
  color: var(--text-tertiary);
  font-size: 12px;
  margin: 6px 0 0;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-weight: 500;
}

.field { margin-bottom: 16px; }
.field label {
  display: block;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 6px;
}
.field input {
  width: 100%;
  padding: 10px 12px;
  font-size: 14px;
  color: var(--text-primary);
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: var(--r-sm);
  transition: all .15s var(--ease-out);
  outline: none;
}
.field input:hover { border-color: var(--border-strong); }
.field input:focus {
  border-color: var(--brand-400);
  box-shadow: 0 0 0 3px var(--brand-50);
}

.err-msg {
  background: #fee2e2;
  color: #991b1b;
  border: 1px solid #fecaca;
  padding: 10px 12px;
  border-radius: var(--r-sm);
  font-size: 13px;
  margin-bottom: 14px;
}

#login-btn {
  width: 100%;
  padding: 11px;
  font-size: 14px;
  font-weight: 600;
  margin-top: 8px;
  color: #fff;
  background: var(--grad-metal);
  background-size: 200% 200%;
  border: none;
  border-radius: var(--r-md);
  box-shadow:
    0 1px 0 rgba(255,255,255,.25) inset,
    0 -1px 0 rgba(0,0,0,.12) inset,
    var(--shadow-brand);
  animation: metal-shift 6s ease-in-out infinite;
  transition: transform .2s var(--ease-out), box-shadow .25s var(--ease-out);
  position: relative; overflow: hidden;
}
#login-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow:
    0 1px 0 rgba(255,255,255,.3) inset, 0 -1px 0 rgba(0,0,0,.15) inset,
    0 14px 32px -10px rgba(79,70,229,.55);
}
#login-btn:active { transform: translateY(1px); }
#login-btn:disabled { opacity: 0.6; cursor: not-allowed; }

.login-footer {
  margin-top: 28px;
  text-align: center;
  font-size: 11px;
  color: var(--text-tertiary);
  letter-spacing: 0.06em;
}