modify HTML with java script to fulfil below

Code:

body {font-family:Verdana, Arial, sans-serif;

background-color: #ffe496;

}

#wrapper { background-color: #efdaae;

color: #000066;

width: 80%;

margin: auto;

min-width:850px;

}

main{

position:relative;

left:50px;

}

#leftcolumn { float: left;

width: 150px;

background-colour: #FFEBC0;

}

#rightcolumn { margin-left: 155px;

background-color: #f7ebde;

color: #000000;

}

header{ background-color: #ccaa66;

color: #00005D;

font-size: 150%;

padding: 10px;

}

#javalogo{

margin: auto;

display:block;

}

h2 { color: #869dc7;

font-family: arial, sans-serif;

}

.content {padding: 20px 20px 0 20px;

}

#floatleft { margin: 10px;

float: left;

}

footer {font-size:70%;

background-color: #ccaa66;

text-align: center;

clear: right;

padding-bottom:20px;

}

nav ul { list-style-type: none;

}

nav a {text-decoration: none;

color: #704f3a;

}

a:visited {

color: #CCaa66;

}

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