Possible to set dimensions for click target

Hello all, I am newby, newby, newby, as you are all used to hearing…!
I’m using a template-based website with basic customisation (trying to code my own later) and I’m trying to increase the size of the click target on my header. The current problem is that only the bottom half of my header logo is clickable.
If you look at my website, jamesmulhollandphoto.com, you will see what I mean.
Here is the code (at least what I think is the right part…):
</style>
<script type=“text/javascript”>
(function($) {
$(document).ready(function () {
$(“#headertext”).click(function() {
$(location).attr(‘href’,‘http://www.jamesmulhollandphoto.com/’);
});
});
})(jQuery);
</script>
<style type=“text/css”>
#headertext { cursor: pointer };
</style>

If anyone can help me with increasing the click target zone to cover (approximately) the whole of my header logo, I’d be most appreciative!

Many thanks to all.

**edit: actually, just looking at the site again, I noticed that the whole white section just above the homepage slideshow image is also clickable - would there be any way to REMOVE this click target zone and restrict it to just around the header logo?
As I said, I’m very new to this etc, so if there’s a relatively simple fix that’d be great… Cheers muchly!

Never mind, I just asked the webmaster to do it as it was bugging me too much.
Will continue to research on future problems…

Thanks anyway!