.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1050; /* encima de la página */
    padding: 16px;
}

.modal-card {
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0,0,0,.2);
    padding: 16px 20px;
    width: 420px;
    max-width: 100%;
}