SOURCE

<div class="box">
	<div class="block">1</div>
	<div class="block">2</div>
	<div class="block">3</div>
	<div class="block">4</div>
</div>

.box {
    display: flex;
    background-color: #fff;
    justify-content: space-around;
}

.block {
    background-color: #ffd200;
    width: 150px;
    height: 150px;
    line-height: 150px;
    color: #fff;
    font-size: 75px;
    text-align: center;
    margin: 5px;
}