// JavaScript Document
<script type="text/javascript">
// make sure to execute this on page load
$(function() {
    // determine if the browser supports transition
    var thisStyle = document.body.style,
    supportsTransition = thisStyle.WebkitTransition !== undefined ||
        thisStyle.MozTransition !== undefined ||
        thisStyle.OTransition !== undefined ||
        thisStyle.transition !== undefined;

    // assign jQuery transition if the browser doesn't support
    if ( ! supportsTransition ) {
        var defaultCSS = {
            backgroundColor: '#F9F9F9'
        },
        hoverCSS = {
            backgroundColor: '#CC0000'
        };

        // loop through each button
        $('.subtle').each(function() {
            var $subtle = $(this);

            // bind an event listener for mouseover and focus
            $subtle.bind('mouseenter focus', function() {
                $subtle.animate(hoverCSS, 500, 'swing' );
            });

            // bind the reverse for mouseout and blur
            $subtle.bind('mouseleave blur', function(ev) {
                if ( ev.type == 'mouseleave' && ev.target == document.activeElement ) return false;

                $subtle.animate(defaultCSS, 500, 'swing' );
            });
        });
    }
});
</script>