.drop-zone {
        border: 2px dashed #dee2e6;
        border-radius: 0.75rem;
        background-color: #f8f9fa;
        transition: all 0.2s ease;
        cursor: pointer;
    }

    .drop-zone:hover {
        background-color: #e9ecef;
        border-color: #adb5bd;
    }

    .drop-zone-dragover {
        background-color: #cfe2ff;
        border-color: #0d6efd;
    }

    .drop-zone .drop-zone-content {
        pointer-events: none;
    }

    .drop-zone .drop-zone-content .btn {
        pointer-events: auto;
    }

    .file-info .badge {
        font-size: 0.9rem;
    }

    .btn-group .btn {
        flex: 1;
    }

    .btn-group .btn-check:checked+.btn {
        background-color: #0d6efd;
        color: #fff;
    }

    .card {
        border-radius: 1rem;
    }

    .card-body {
        border-radius: 1rem;
    }

    .drop-zone.is-invalid {
        border-color: #dc3545;
        background-color: #f8d7da;
    }