JSFiddle - React, Tailwind, and code Playground

HTML

<div class="box1">1</div>
<div class="box2">2
    <dic class="box2-1">2-1</dic>
</div>

CSS

div {
    width: 100px;
    height: 100px;
    float: left;
    cursor: pointer;
}
.box1 {
    background: red;
}
.box2 {
    background: green;
    position: relative;
}
.box2-1 {
    background: blue;
    position: absolute;
    top: 0;
    left: -30px;
}
div:hover {
    border: 5px solid orange;
}