.preloader-main{
    position: fixed;
    top: 0;
    left: 0;
    pointer-events: none;
    z-index: 100;
    width: 100%;
    height: 100%;
    background: white;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all .25s linear;
    opacity: 0;
}

.preloader-main.visible{
    opacity: 1;
}