style.css

body {
    margin: 0px;
    padding: 0px;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

button {
    border: 1px solid black;
    border-radius: 2px;
    font-size: 1.2rem;
    background: white;
    color: black;
    transition: .5s;
    cursor: pointer;
}

button:hover {
    background: black;
    color: white;
}

.overlay {
    position: fixed;
    background: rgba(0, 0, 0, .5);
    left: 0%;
    right: 0%;
    top: 0%;
    bottom: 0%;
    visibility: hidden;
    transition: .3s;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0px;
    transition: .5s;
}

.modal {
    width: 200px;
    background: white;
    border-radius: 5px;
    /*animation: modalIn .5s forwards;*/
    animation-delay: .5s;
    animation-timing-function: cubic-bezier(.43, -0.55, .71, 1.3);
    animation-iteration-count: 1;
    transform: translateY(-700px);
    display: flex;
    flex-direction: column;
}

.modal-button {
    cursor: pointer;
    font-size: 1.3rem;
    color: grey;
    background: white;
    display: flex;
    justify-content: center;
    align-items: center;
    align-self: flex-end;
    margin: 1px 2px;
    will-change: transform;
    transition: .2s;
}

.modal-button:active {
    transform: scale(.3);
}

.modal-button:hover {
    background: white;
    color: black;
}

.modal-content {
    text-align: center;
    font-family: Arial;
}

.overlay.active {
    visibility: visible;
}

@keyframes modalIn {
    from {
        transform: translateY(-700px);
    }
    to {
        transform: translateY(0px);
    }
}

@keyframes modalOut {
    from {
        transform: translateY(0px);
    }
    to {
        transform: translateY(-700px);
    }
}