.burger {
    width: 30px;
    height: 17px;
    transform: rotate(0deg);
    transition: .5s ease-in-out;
    cursor: pointer;
    position: relative;  
    z-index: 2000;

    span {
        display: block;
        position: absolute;
        height: 4px;
        width: 100%;
        background: $color-white;
        opacity: 1;
        left: 0;
        transform: rotate(0deg);
        transition: .25s ease-in-out;

        &:nth-child(1) {
            top: 0px;
        }

        &:nth-child(2),
        &:nth-child(3) {
            top: 7px;
        }

        &:nth-child(4) {
            top: 14px;
        }
    }

    &.open{
        span{

            &:nth-child(1) {
                top: 18px;
                width: 0%;
                left: 50%;
            }

            &:nth-child(2) {
                transform: rotate(45deg);
            }

            &:nth-child(3) {
                transform: rotate(-45deg);
            }

            &:nth-child(4) {
                top: 18px;
                width: 0%;
                left: 50%;
            }
        }
    }
}