JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>IG Indy Gamers</title>
<link rel="stylesheet" type="text/css" href="mycss.css" media="screen" />
<link href="styles.css" rel="stylesheet" type="text/css">
<link rel="stylesheet" href="colorbox.css" />



</head>
<body>
<div id="maincontainer">
<div id="topsection" ><div class="innertube"> 
 TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION  TOP SECTION
    
    </div>
    </div>


<!--  CONTENT START -->
<div id="contentwrapper">
<div id="contentcolumn">
  <div class="innertube"> 
<table bgcolor="red"><tr><td><h1>MIDDLE SECTION MIDDLE SECTION  MIDDLE SECTION  MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION  MIDDLE SECTION  MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION  MIDDLE SECTION  MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION  MIDDLE SECTION  MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION  MIDDLE SECTION  MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION MIDDLE SECTION</h1></td></tr></table>      
</div>
</div> 
        </div>
   
    
        
<div id="leftcolumn">
<div...

CSS

body{
margin:0;
padding:0;
line-height: 1.5em;
color: black;
height: 100%;
}

b{font-size: 110%;}
em{color: red;}
a{color: blue;}



/*TOPSECTION */
#topsection{
background: red;
background-position: left top, left top;
background-repeat: no-repeat, repeat;
height: 200px; /*Height of top section*/
color: White;
text-align:center;
min-width: 950px;
}


/* CONTENT */
#contentwrapper{
float: left;
width: 100%;
min-width: 1000px;
background: white;
}

#contentcolumn{
margin: 0 20% 0 20%; /*Margins for content column. Should be "0 RightColumnWidth 0 LeftColumnWidth*/
}



/* LEFT COLUMN */
#leftcolumn{
float: left;
width: 20%; /*Width of left column in percentage*/
margin-left: -100%;
background: blue;
}


/* RIGHT COLUMN */
#rightcolumn{
float: left;
width: 20%; /*Width of right column in pixels*/
margin-left: -20%; /*Set margin to that of -(RightColumnWidth)*/
background: blue;
}

/* FOOTER */
#footer{
clear: left;
width: 100%;
background: black;
color: #5f5f5f;
text-align: center;
padding: 4px 0;
}

#footer a{
color: #FFFF80;
}

/*OTHER*/
.innertube{
margin: 10px; /*Margins for inner DIV inside each column (to provide padding)*/
margin-top: 0;
}