Add an "active" class selector with the appropriate styles:
.product-link:hover,
.product-link.active {
background: #E6DCD0;
}
Add the "active" class to the first link:
<div id="link0" class="product-link active">
Add / remove the "active" class in the
boxActivate
function:
var boxActivate = function(id){
$links.removeClass("active");
$boxes.hide().filter('#box' + id).show().closest(".product-link").addClass("active");
}
You'll also want to set the initial display state for the second and third boxes to "none".
Updated demo[
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