.multi-site-popup {
        display: flex;
        justify-content: center;
        align-items: center;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background-color: rgba(0, 0, 0, 0.5);
        z-index: 999;
        transition: opacity 0.3s ease;
    }

    .popup-content {
        background-color: #fff;
        max-width: 600px;
        width: 100%;
        padding: 30px;
        border-radius: 10px;
    }

    .close-btn {
        font-size: 1.5rem;
        background: transparent;
        border: none;
        cursor: pointer;
    }

    .form-control, .form-select {
        border-radius: 10px;
    }

    .btn {
        transition: background-color 0.3s ease;
    }

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

    .form-control:focus, .form-select:focus {
        border-color: #0056b3;
        box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
    }

    .btn-lg {
        padding: 12px 20px;
        font-size: 1.125rem;
    }