display or hide header shopping sidebar

First look at Html code for header sidebar

<li class="top-cart">
        <div class="block-title">
        <strong id="cartHeader"><a href="http://lifemore.svn-test.com/index.php/checkout/cart/">shopping bag (<span>1</span>)</a></strong>
    </div>
	<span class="icon"></span>
    <div class="block-content" id="topCartContent">
        <div class="inner-wrapper">                            <p class="block-subtitle">
                <span class="close-btn" onclick="Enterprise.TopCart.hideCart()">Close</span>
                Recently added item(s)            </p>

 Add this style to the css file will make it active.

<style>
.top-cart .block-content {
    display: none;
}
.top-cart:hover .block-content  {
    display: block;
}
</style>