Dynamic css files using scss

I’m trying change the value of a scss variable dynamically using rails
3.1.

For example:

In a example.css.scss

$main-color: red;
body {
background-color: $main-color;
color: #333;
font-family: verdana, arial, helvetica, sans-serif;
font-size: 13px;
line-height: 18px; }

And in the model user, I put the field color_prefered. And I want to
change the value of a $main-color with the value of user.color_prefered.

Is it possible?

Tk.
Rafa.

This is a heck of a lot easier to do in the presentation than the style.
Consider this:

body
.red
background-color: red
.green
background-color: green

Stuff inside

In your controller (or application controller), simply set
@theme_main_color to whatever you want.