JSFiddle - React, Tailwind, and code Playground

HTML

<div class="content two-column">
    <div class="big-block">Big block</div>
    <div class="two-column">
        <div class="small-block">Small block 1</div>
        <div class="small-block">Small block 2</div>
        <div class="small-block">Small block 3</div>
        <div class="small-block">Small block 4</div>
        <div class="small-block">Small block 5</div>
        <div class="small-block">Small block 6</div>
    </div>
</div>

CSS

.content {
    height: 130px;
}
.two-column {
    -moz-column-count: 2; /* Для Firefox */
    -webkit-column-count: 2; /* Для Safari и Chrome */
    column-count: 2;
}
.big-block {
    background: red;
    line-height: 50px;
}
.small-block {
    background: gray;
    line-height: 50px;
}