* {
    margin: 0;
    padding: 0;
}
#nav-icon3 span:nth-child(1) {
    top: 0px;
}

#nav-icon3 span:nth-child(2), #nav-icon3 span:nth-child(3) {
    top: 18px;
}

#nav-icon3 span:nth-child(4) {
    top: 36px;
}

#nav-icon3.open span:nth-child(1) {
    top: 18px;
    width: 0%;
    left: 50%;
}

#nav-icon3.open span:nth-child(2) {
    -webkit-transform: rotate(45deg);
    -moz-transform: rotate(45deg);
    -o-transform: rotate(45deg);
    transform: rotate(45deg);
}

#nav-icon3.open span:nth-child(3) {
    -webkit-transform: rotate(-45deg);
    -moz-transform: rotate(-45deg);
    -o-transform: rotate(-45deg);
    transform: rotate(-45deg);
}

#nav-icon3.open span:nth-child(4) {
    top: 18px;
    width: 0%;
    left: 50%;
}