Как сделать простую подсветку кода в HTML средствами JS (Примеры)

<style type="text/css">
        .columns { width:100%; display:table; } 
        .columns .a, .columns .b, .columns .c {
            //float: left; 
            //clear:right; 
            display:table-cell; 
        } 
        .columns .a { width:30%; background: #ccffcc; }
        .columns .b { width:40%; background: #ffcccc; } 
        .columns .c { width: 30%; background: silver; } 
</style>

<script type="text/javascript">

/* загрузка HTML-редактора аяксом */
function load_editor( obj ) {

	// set editor position using cookie data
	try {
		cookie = document.cookie.split("; ")
		for(i in cookie) {
			item = cookie[i].split("=");
			if( obj.id == item[0] ) {
				pos = item[1].split(",");
				obj.style.left = pos[0];
				obj.style.top = pos[1];
			}
		}
	}
	catch(e) {}
	
	//loading ajax editor
	if( !obj.editor_loaded ) {
		x.ajax({action: "files/editor.html", elements: []}, function( data ){
			    obj.innerHTML += data;
			    obj.editor_loaded = true;
		}, "get");
	}
	
	// show & hide editor
	obj.style.visibility = !obj.style.visibility || obj.style.visibility == "hidden" ? "visible" : "hidden";
}
</script>

<?php

define( _site_url_, $_SERVER["DOCUMENT_ROOT"]);
define( _site_templates_, _site_url_ . "/source/pages/");
define("_partition_param_", "partition");

function parse_template( $ext = ".html" ) {

	$mod_rewrite_on = substr_count(strtolower($_SERVER["SERVER_SOFTWARE"]), "apache") && in_array("mod_rewrite", apache_get_modules()) ? true : false;
	$current_url = parse_url( $_SERVER["REQUEST_URI"] );
	
	if( $mod_rewrite_on ) list(,$partition) = explode("/", $current_url["path"]);
	else $partition = $_GET[ _partition_param_ ];
	
	$partition = htmlspecialchars($partition, ENT_QUOTES);

	if( !is_file(_site_templates_ . $partition . $ext) ) $partition = "index";
	include _site_templates_ . $partition . $ext;
}

include_once _site_url_. "/scripts/news/include.php";
parse_template();

?>

<!-- HTML-comment single line -->
<div class="columns"> 
        <div class="a" title="Бла бла"> 
                Колонка шириной 30% 
                <div style="width:200px; font-size:9px; background:black; color:white; text-align:center;">spacer</div> 
        </div> 
        <div class="b">Колонка шириной 40%, которая не скачет</div> 
        <div class="c">Колонка шириной 30% </div> 
</div> 

<br clear="all" />
Some text...