JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrapper">
	<div id="main">
		<div class="header">


		</div>
		<div class="cnt">
			<div id="sidebar_left_parent">
                <div class="sidebar_left"></div>
                <div class="sidebar_left"></div>
                <div class="sidebar_left"></div>
			</div>
			
            <div id="sidebar_right_parent">

			</div>
            
			<div id="content">
			</div>
			
			<div class="clear"></div>
			<div id="footer">
			</div>
		</div>
	</div>	
</div>

CSS

#main{
	margin: 0 auto;
	background: #eaeaea;
	width: 1000px;
	height: 900px;
}

.clear{
	clear: both;
}
.header{
	width: 100%;
	height: 190px;
}

#sidebar_left_parent {
	width: 185px;
	background: #000000;
	position: relative;
	float: left;
}

#content{
	width: 630px;
	height: 600px;
	position: relative;
    margin: 0 185px 0 185px;
	background: #ffffff;
}

#sidebar_right_parent { 
	width: 185px;
	height: 250px;
	background: #41b2f2;
	float: right;
	position: relative;
}

.sidebar_left {
    width:185px;
    height:200px;
    margin-bottom:20px;
    background:#666;
}