JSFiddle - React, Tailwind, and code Playground

HTML

<div id="main"></div>

CSS

#main {
    width:200px;
    height:300px;
    background:#000;
}
#main:before {
    content:'im before';
    position:fixed;
    left:0px;
    top:0px;
    width:40px;
    height:40px;
    background:blue
}

JavaScript

$("#main").hover(function () {
    $(this).animate({
        "margin-left": "40px"
    });
    $("#main:before").animate({
        "margin-left": "40px"
    });
}, function () {
    $(this).animate({
        "margin-left": "0px"
    });
    $("#main:before").animate({
        "margin-left": "0px"
    });
});