Link Click To Hide / Show Series Of DIV

I'm basically trying to make it so a link click will hide and display a series of DIVs to make my site look a bit neater and more professional. The code I have WORKS, it can make a DIV appear and disappear easily enough but the issue I'm having is that it only works if you click the same link to show nad hide. Click a link to show a DIV then click another link and both will be visible.

But the only other code I tried to hide all but the selected DIV just results in my page becoming invisible (Its constructed with DIVs from top to bottom) so its not a suitable result. I'm basically after this: [URL]. Where you click on the link (in this case an image) and it shows what you need. I did try searching through their HTML and code but their javascript file appears as one long string to me so its hard to find any real useful detail.

This is the code I have at the moment:
Code JavaScript:
function showHide(shID) {
if (document.getElementById(shID)) {
if (document.getElementById(shID).style.display != 'block') {
document.getElementById(shID).style.display = 'block';
}else {
document.getElementById(shID).style.display = 'none';
}}}

And this is my current page in practice. [URL]. I'm assuming I might need an array but I need to stop it picking on every DIV and only the DIVs in my content area.