jfa-go/css/modal.css

.modal {
    display: none;
    position: fixed;
    z-index: 1;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,40%);
}

.modal-shown {
    display: block;
}

@keyframes modal-hide {
    from { opacity: 1; }
    to { opacity: 0; }
}

.modal-hiding {
    animation: modal-hide 0.2s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

@keyframes modal-content-show {
    from {
        opacity: 0;
        top: -6rem;
    }
    to {
        opacity: 1;
        top: 0;
    }
}

.modal-content {
    position: relative;
    margin: 10% auto;
    width: 30%;
}

.modal-shown .modal-content {
    animation: modal-content-show 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

@media screen and (max-width: 400px) {
    .modal-content {
        width: 90%;
    }
}

.modal-close {
    float: right;
    color: #aaa;
    font-weight: normal;
}

.modal-close:hover,
.modal-close:focus {
    filter: brightness(60%);
}