.menu-anchor {
    margin-left: -9px;
    margin-top: -2px;
    width: 40px;
    height: 32px;
    display: inline-block;
    vertical-align: middle;
    position: relative;
    text-indent: -9999px;
    overflow: hidden;
    cursor: pointer;
    background: #FFF;
}

.menu-anchor:before {
    content: "";
    display: block;
    margin: 7px auto;
    width: 70%;
    height: 0.25em;
    background: #000;
    box-shadow: 0 .45em 0 0 #000, 0 .9em 0 0 #000;
}

.menu-active .menu-anchor {background: #fff}

menu {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 19999;
    width: 80vw;
    height: 100%;
    margin: 0px;
    padding: 20px;
    background: #FFF;
    box-shadow: inset -5px -10px 10px 0 rgba(0,0,0,.3);
    overflow-x: auto;
}

menu {
    -webkit-transform: translateX(-80vw);
    -moz-transform: translateX(-80vw);
    -ms-transform: translateX(-80vw);
    transform: translateX(-80vw);
    -webkit-transition: all .25s linear;
    -moz-transition: all .25s linear;
    -ms-transition: all .25s linear;
    transition: all .25s linear;
}

.menu-active {
    -webkit-transform: translateX(0);
    -moz-transform: translateX(0);
    -ms-transform: translateX(0);
    transform: translateX(0);
}