.height{
    min-height: 100vh;
}
#bottom-top{
    position: fixed;
    bottom: 20px;
    right: 20px;
    box-shadow: 0 0 8px 0 #000;
    padding: 5px;
    border-radius: 5px;
    --size: 25px;
    height: var(--size);
    width: var(--size);
    display: grid;
    place-content: center;
    opacity: 0;
    visibility: hidden;
    background-color: #fcfcfc;
    fill: #000;
}
#bottom-top svg{
    --size: 15px;
    height: var(--size);
    width: var(--size);
}
#bottom-top.show{
    opacity: 1;
    visibility: visible;
}