* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    border-bottom: 1px solid #e9ecef;
    margin-bottom: 30px;
}

header h1 {
    color: #007bff;
}

.user-menu {
    display: flex;
    align-items: center;
    gap: 15px;
}

.btn {
    display: inline-block;
    padding: 8px 16px;
    border: none;
    border-radius: 4px;
    text-decoration: none;
    cursor: pointer;
    font-size: 14px;
    transition: background 0.3s;
}

.btn-primary {
    background-color: #007bff;
    color: white;
}

.btn-primary:hover {
    background-color: #0056b3;
}

.btn-secondary {
    background-color: #6c757d;
    color: white;
}

.btn-secondary:hover {
    background-color: #545b62;
}

.btn-outline {
    background-color: transparent;
    border: 1px solid #007bff;
    color: #007bff;
}

.btn-outline:hover {
    background-color: #007bff;
    color: white;
}

.btn-danger {
    background-color: #dc3545;
    color: white;
    padding: 4px 8px;
    font-size: 12px;
}

.btn-danger:hover {
    background-color: #c82333;
}

.btn-group {
    display: flex;
    gap: 10px;
    margin-top: 20px;
}

.form-container {
    background: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    max-width: 600px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}

.form-group input {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
}

.card {
    background: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}

.dashboard .card {
    margin-top: 20px;
}

.alert {
    padding: 12px;
    margin-bottom: 20px;
    border-radius: 4px;
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-info {
    background-color: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

.text-center {
    text-align: center;
}

.mt-20 {
    margin-top: 20px;
}

/* 统计卡片 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: white;
    padding: 20px;
    border-radius: 8px;
    text-align: center;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.stat-number {
    font-size: 24px;
    font-weight: bold;
    color: #007bff;
    margin: 10px 0;
}

/* 表格 */
.table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

.table th,
.table td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

.table th {
    background-color: #f8f9fa;
    font-weight: bold;
}

.status-available { color: green; }
.status-used { color: orange; }
.status-deleted { color: red; }

.pagination {
    display: flex;
    justify-content: center;
    margin-top: 20px;
    gap: 5px;
}

.pagination a {
    padding: 8px 12px;
    text-decoration: none;
    border: 1px solid #ddd;
    color: #007bff;
}

.pagination a.active {
    background-color: #007bff;
    color: white;
}

.pagination a:hover:not(.active) {
    background-color: #f8f9fa;
}