body {
  font-family: 'Inter', 'Noto Sans SC', sans-serif;
  transition: background-color 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
}

/* Glassmorphism Navigation */
.navbar {
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  background-color: rgba(var(--bs-body-bg-rgb), 0.8) !important;
  border-bottom: 1px solid rgba(var(--bs-body-color-rgb), 0.1);
}

.navbar-brand {
  letter-spacing: 1px;
}

/* 渐变与动效卡片 */
.system-card {
  border: none;
  border-radius: 15px;
  background: var(--bs-body-bg);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

[data-bs-theme="dark"] .system-card {
  background: rgba(var(--bs-dark-rgb), 0.8);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  border: 1px solid rgba(255,255,255,0.05);
}

.system-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
}

[data-bs-theme="dark"] .system-card:hover {
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.6);
}

.login-title {
  font-weight: 800;
  background: linear-gradient(135deg, #0d6efd, #0dcaf0);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

[data-bs-theme="dark"] .login-title {
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* 主容器居中与自适应高度 */
.content-wrapper {
  min-height: calc(100vh - 180px);
}

/* 按钮改进 */
.btn-primary {
  background: linear-gradient(135deg, #0d6efd, #0b5ed7);
  border: none;
  letter-spacing: 0.5px;
  font-weight: 600;
  transition: all 0.2s ease-in-out;
}

.btn-primary:hover {
  background: linear-gradient(135deg, #0b5ed7, #0a58ca);
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(13, 110, 253, 0.3);
}

[data-bs-theme="dark"] .btn-primary {
  background: linear-gradient(135deg, #3b82f6, #6366f1);
}

[data-bs-theme="dark"] .btn-primary:hover {
  background: linear-gradient(135deg, #2563eb, #4f46e5);
  box-shadow: 0 5px 15px rgba(99, 102, 241, 0.3);
}

/* 输入框焦点动画 */
.form-control {
  border-radius: 8px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.form-control:focus {
  border-color: #8b5cf6;
  box-shadow: 0 0 0 0.25rem rgba(139, 92, 246, 0.25);
}

/* Footer 微调 */
.footer {
  font-size: 0.9rem;
  background: transparent;
}