different colors in each columns

Hi guys,
thirst of all let me thank to all of you who have created this shopping cart and this website. Excellent job!

I started to create my own template, I keep three colums on the main page, but each column has different background color (I create new classes in stylesheet.css derived from .box .middle class and changed reference to this class in tpl file for each module (for example - 3rd row in category.tpl <div id="category" class="middle_yellow"><?php echo $category; ?></div>). It works, but it is not the best way, I do not respect the choice of column side (right/left) from the admin menu. What is the variable which dedicate to which column a module will be placed ?

there is no variable. It is stored in the db.

Not entirely the case... The values of all the settings are set in the index.php file to the $config object.
You can use:
$this->config->get('module_position');

where module is the name of the particular module.
(latest, bestseller, cart, information, etc)

The value is 'left' or 'right'

thanks, it is what I looked for