How do we change the colors in the WordPress 1.5 Default theme?

I’ve recently switched from Blogger to WordPress. While the installation was very easy, I’ve found my self at a loss since then. Are there any basic, step by step tutorials teaching people how to modify the default theme? I haven’t found any.

I’ve been trying to make my theme look more like the rounders3 template from blogger. Naturally enough, I’ve been trying to do so by editing the styles.css file. However, the color changes I’ve made have had NO EFFECT. For example, observe this snippet from my styles.css:

Sans-Serif;
background-color: #246;
color: #ccc;
text-align: center;
}

#page {
background-color: #eec;
border: 1px solid #959596;
text-align: left;
}

My background should be dark bluish, and my page should be light yellow, right? Unfortunately, neither changed at all, and the page is still white. Why is wordpress ignoring the colors I set in my styles.css?