/* 自定义样式 */
body {
    /* background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); */
    background-color: #f5f5f5;
    min-height: 100vh;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.card {
    border: none;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
}

.card-header {
    border-radius: 15px 15px 0 0 !important;
    border: none;
}

.form-control, .form-select {
    border-radius: 8px;
    border: 1px solid #e1e5e9;
    padding: 8px 10px;
    transition: all 0.3s ease;
}

.form-control:focus, .form-select:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 0.2rem rgba(102, 126, 234, 0.25);
}

.btn {
    border-radius: 8px;
    padding: 12px 24px;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-outline-secondary {
    border-color: #6c757d;
    color: #6c757d;
}

.btn-outline-secondary:hover {
    background-color: #6c757d;
    border-color: #6c757d;
}

.table {
    border-radius: 8px;
    overflow: hidden;
}

.table th {
    background-color: #f8f9fa;
    border-bottom: 2px solid #dee2e6;
    font-weight: 600;
}

.alert {
    border-radius: 8px;
    border: none;
}

.text-success {
    color: #28a745 !important;
    font-weight: 600;
}

.text-danger {
    color: #dc3545 !important;
    font-weight: 600;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }
    
    .card {
        margin: 20px 0;
    }
    
    .btn {
        width: 100%;
        margin-bottom: 10px;
    }
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid #ffffff;
    border-radius: 50%;
    border-top-color: transparent;
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* 表单验证样式 */
.is-invalid {
    border-color: #dc3545 !important;
}

.invalid-feedback {
    display: block;
    width: 100%;
    margin-top: 0.25rem;
    font-size: 0.875em;
    color: #dc3545;
}