JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrapper">
    <div id="left">
        <div id="left_block_one"></div>
        <div id="left_block_two"></div>        
    </div>
    <div id="middle"></div>
    <div id="right"></div>
    <div id="footer"></div>
</div>

CSS

#wrapper {
    width: 600px;
    height: 600px;
    background-color: #cecece;
}
#left {
    width: 150px;
    height: 490px;
    background-color: green;
    float: left;
    padding-top: 10px;
}
#middle {
    width: 300px;
    height: 500px;
    background-color: blue;
    float: left;
}
#right {
    width: 150px;
    height: 500px;
    background-color: green;
    float: left;
}
#left_block_one {
    width: 60px;
    height: 60px;
    float: left;
    margin-left: 10px;
    background-color: red;
}
#left_block_two {
    width: 60px;
    height: 60px;
    float: right;
    margin-right: 10px;
    background-color: red;
}
#footer {
    width: 600px;
    height: 100px;
    float: left;
    background-color: #666;
}