Making a line move smoothly under my navbar
<p>So I'm trying some stuff out for webdesign but I'm having a bit of a problem with the following idea:</p>

<p>So I'm trying to make a litte .png line I made move smoothly under my navbar. So when I click on another link it slidestowards it and stays there as long as that site is active, but I'm having a bit of a problem finding the code, even tried making it myself.</p>

<p>If anybody has a usefull link for this or a code they wrote before, it would be really appreciated.</p>
