On the site new3.thesciencecouincil.com I'd like to reduce the space above and between the 5 buttons (under the img with planet earth in it).

The buttons are custom html modules.
<p><a href="index.php?option=com_content&view=category&layout=blog&id=11&Itemid=116"><img src="images/buttons/button-role-of-energy.jpg" alt="" /></a></p>

Using the inspector I see a margin around the img even though I've set it to 0px
.top-2 {
padding: 0px;
margin: 0px;
}

I'd like the spacing between the buttons to be 1/2 of what it is now and the space above the buttons to be 1/2 of current space.
I suspect that the solution is something I've overlooked.
What next?

thanks,

Keith