:root {
  --primary: #2F3B52;
  --primary-light: #3d4d6b;
  --accent: #FF8C42;
  --text: #333;
  --text-sub: #6B7488;
}

* { box-sizing: border-box; }

html, body { height: 100%; margin: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", "Noto Color Emoji", sans-serif;
  /* 默认渐变背景：未设置自定义背景时使用，保证登录页始终美观 */
  background: linear-gradient(135deg, #e5edf7 0%, #cdd9ec 100%);
  color: var(--text);
}

/* 背景图上叠加半透明遮罩，保证卡片文字清晰可读 */
.login-mask {
  position: fixed;
  inset: 0;
  background: rgba(20, 28, 43, .45);
}

.login-wrap {
  position: relative;
  z-index: 1;
  min-height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.login-card {
  width: 100%;
  max-width: 380px;
  background: #fff;
  border-radius: 16px;
  box-shadow: 0 18px 50px rgba(20, 28, 43, .28);
  padding: 40px 34px 34px;
  text-align: center;
}

.login-brand {
  font-size: 46px;
  line-height: 1;
  margin-bottom: 10px;
}

.login-title {
  font-size: 22px;
  font-weight: 700;
  margin: 6px 0 4px;
  color: var(--primary);
  letter-spacing: .5px;
}

.login-sub {
  margin: 0 0 26px;
  color: var(--text-sub);
  font-size: 14px;
}

.login-form { text-align: left; }

.login-field { display: block; margin-bottom: 18px; }

.login-label {
  display: block;
  font-size: 13px;
  color: var(--text-sub);
  margin-bottom: 7px;
  font-weight: 600;
}

.login-field input {
  width: 100%;
  height: 46px;
  padding: 0 14px;
  border: 1px solid #d9e0ec;
  border-radius: 10px;
  font-size: 15px;
  color: var(--text);
  background: #fbfcfe;
  outline: none;
  transition: border-color .18s, box-shadow .18s, background .18s;
}

.login-field input::placeholder { color: rgba(107, 116, 136, .85); }

.login-field input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(47, 59, 82, .12);
  background: #fff;
}

.login-err {
  margin: -4px 0 14px;
  padding: 10px 12px;
  background: #fdecea;
  color: #c0392b;
  border-radius: 9px;
  font-size: 13px;
  text-align: center;
}

/* 「记住密码」复选框 */
.login-remember {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: -6px 0 16px;
  font-size: 13px;
  color: var(--text-sub);
  cursor: pointer;
  user-select: none;
}

.login-remember input[type="checkbox"] {
  width: 16px;
  height: 16px;
  accent-color: var(--primary);
  cursor: pointer;
}

.login-btn {
  width: 100%;
  height: 48px;
  border: none;
  border-radius: 10px;
  background: var(--primary);
  color: #fff;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 4px;
  cursor: pointer;
  transition: background .18s, transform .05s;
}

.login-btn:hover { background: var(--primary-light); }
.login-btn:active { transform: translateY(1px); }
.login-btn:disabled { opacity: .65; cursor: default; }

.login-foot {
  margin-top: 18px;
  color: rgba(255, 255, 255, .9);
  font-size: 12px;
  text-shadow: 0 1px 2px rgba(0, 0, 0, .3);
}