JSFiddle - React, Tailwind, and code Playground

by Elena Shevchuk

HTML

<div class="a">
    <div class="b"></div>
</div>

CSS

body {
    background-image: url("http://cdn.joxi.ru/uploads/prod/2014/04/07/45d/afa/ec4fd2a3737512a2cf6819c432a0138a6058aa72.jpg");
    padding-left: 100px;
    padding-top: 100px;
    position: relative;
    z-index: 1;
}
.a {
    left: 100px;
    top: 50px;
    width: 100px;
    height: 100px;
    position: absolute;
    background: blue;
    opacity: .5;
}
.b {
    width: 100px;
    height: 100px;
    top: 50px;
    left: -50px;
    position: absolute;
    background: green;
    opacity: .5;
    z-index: -1;
}