Not working (need Help)

[ali Khan]

I want to use this in Opencart for :checked in IE7 and IE8

I copied this in header.tpl where all my scripts and css files are link but its not working

<!--[if (gte IE 6)&(lte IE 8)]>
<script type="text/javascript" src="catalog/view/theme/default/stylesheet/selectivizr.js"></script>
<noscript><link rel="stylesheet" href="[fallback css]" /></noscript>
<![endif]-->