:root {
    --primary: #4a90d9;
    --primary-dark: #357abd;
    --primary-light: #e8f0fe;
    --success: #28a745;
    --danger: #dc3545;
    --warning: #ffc107;
    --info: #17a2b8;
    --gray-50: #f8f9fa;
    --gray-100: #f1f3f5;
    --gray-200: #e9ecef;
    --gray-300: #dee2e6;
    --gray-400: #ced4da;
    --gray-500: #adb5bd;
    --gray-600: #6c757d;
    --gray-700: #495057;
    --gray-800: #343a40;
    --gray-900: #212529;
    --shadow: 0 2px 8px rgba(0,0,0,0.08);
    --shadow-lg: 0 4px 16px rgba(0,0,0,0.12);
    --radius: 8px;
    --radius-lg: 12px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    background: var(--gray-100);
    color: var(--gray-800);
    line-height: 1.6;
}

.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 6px;
    padding: 8px 20px; border: none; border-radius: var(--radius);
    font-size: 14px; font-weight: 500; cursor: pointer;
    transition: all 0.2s; text-decoration: none;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-success { background: var(--success); color: #fff; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-warning { background: var(--warning); color: var(--gray-800); }
.btn-info { background: var(--info); color: #fff; }
.btn-outline { background: transparent; border: 1px solid var(--gray-300); color: var(--gray-700); }
.btn-outline:hover { background: var(--gray-100); }
.btn-sm { padding: 4px 12px; font-size: 12px; }
.btn-lg { padding: 12px 32px; font-size: 16px; }
.btn-block { width: 100%; }

.form-group { margin-bottom: 16px; }
.form-group label {
    display: block; margin-bottom: 6px;
    font-size: 14px; font-weight: 500; color: var(--gray-700);
}
.form-control {
    width: 100%; padding: 10px 14px;
    border: 1px solid var(--gray-300); border-radius: var(--radius);
    font-size: 14px; transition: border-color 0.2s;
    background: #fff; color: var(--gray-800);
}
.form-control:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(74,144,217,0.15); }
select.form-control { appearance: auto; }

.card {
    background: #fff; border-radius: var(--radius-lg);
    box-shadow: var(--shadow); overflow: hidden;
}
.card-header {
    padding: 16px 20px; border-bottom: 1px solid var(--gray-200);
    font-weight: 600; font-size: 16px; display: flex;
    align-items: center; justify-content: space-between;
}
.card-body { padding: 20px; }

.table-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th, td { padding: 10px 14px; text-align: left; font-size: 14px; }
th { background: var(--gray-50); color: var(--gray-600); font-weight: 600; border-bottom: 2px solid var(--gray-200); }
td { border-bottom: 1px solid var(--gray-200); }
tr:hover td { background: var(--gray-50); }

.badge {
    display: inline-block; padding: 2px 10px; border-radius: 20px;
    font-size: 12px; font-weight: 500;
}
.badge-success { background: #d4edda; color: #155724; }
.badge-danger { background: #f8d7da; color: #721c24; }
.badge-warning { background: #fff3cd; color: #856404; }
.badge-info { background: #d1ecf1; color: #0c5460; }

.modal-overlay {
    display: none; position: fixed; top: 0; left: 0;
    width: 100%; height: 100%; background: rgba(0,0,0,0.5);
    z-index: 1000; align-items: center; justify-content: center;
}
.modal-overlay.active { display: flex; }
.modal {
    background: #fff; border-radius: var(--radius-lg); width: 90%;
    max-width: 500px; max-height: 85vh; overflow-y: auto;
}
.modal-header {
    padding: 16px 20px; border-bottom: 1px solid var(--gray-200);
    display: flex; align-items: center; justify-content: space-between;
    font-weight: 600;
}
.modal-header .close { background: none; border: none; font-size: 24px; cursor: pointer; color: var(--gray-500); }
.modal-body { padding: 20px; }
.modal-footer { padding: 12px 20px; border-top: 1px solid var(--gray-200); display: flex; gap: 10px; justify-content: flex-end; }

.toast-container {
    position: fixed; top: 20px; right: 20px; z-index: 2000;
    display: flex; flex-direction: column; gap: 8px;
}
.toast {
    padding: 12px 20px; border-radius: var(--radius);
    color: #fff; font-size: 14px; animation: slideIn 0.3s ease;
    box-shadow: var(--shadow-lg);
}
.toast-success { background: var(--success); }
.toast-danger { background: var(--danger); }
.toast-info { background: var(--info); }

@keyframes slideIn {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

.empty-state {
    text-align: center; padding: 60px 20px; color: var(--gray-500);
}
.empty-state .icon { font-size: 48px; margin-bottom: 12px; }
.empty-state p { font-size: 14px; }