JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/css/bootstrap.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/css/bootstrap-theme.min.css">
    <div class="bg col-xs-4">1</div>
    <div class="bg col-xs-4">2</div>
    <div class="col-xs-4">
        <div class="row">
            <div class="bg col-xs-12">3</div>
            <div class="bg col-xs-12">4</div>
        </div>
    </div>

    <div class="bg col-xs-4">5</div>
    <div class="bg col-xs-4">6</div>
    <div class="bg col-xs-4">7</div>

CSS

.bg {
    position: relative;
    background: red;
    height: 200px;
    text-align: center;
    font-size: 20px;
    color: #fff;
    padding-top: 90px;
}
.bg:after {
    content: ' ';
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    width: 1px;
    height: 100%;
    background: #fff;
}
.bg:before {
    content: ' ';
    position: absolute;
    top: 0;
    right: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: #fff;
}