I'm running a Formula 1 website on Joomla and I don't much about web designing. The webmaster is our of town and I want to make my news topic more dark. How should I go about it?

www.f1passionates.com

you can change the color with a program like photoshop or somethink like this.
Go on your webserver to "images/main/light-item-bg.png" and change the file as u want