Hello there!
I've begun theming for Drupal 7 and have encountered some issues. First I attempted to build upon an existing theme made for theme dev, Framework. That worked moderately well, but it's way too messy because I had to mix both my own already existing css with css of another theme.
I've now started from scratch, which has worked out quite well. My page.tpl.php file has been customized to my needs. The regions are working and the region demo shows me the regions exactly where they should be.
However, the styling of content that gets put in is wrong. Well, let me correct myself, it's not wrong but it shouldn't exist. When I view my page's source after it's been renderen I am seeing a ton of new divs with classes and id's that don't even exist in my stylesheet. For example:
<div id="block-system-navigation" class="block block-system contextual-links-region block-menu">
<h2>Navigation</h2>
<div class="contextual-links-wrapper contextual-links-processed">
<div class="content">
<ul class="menu">
<li class="first last collapsed">
</ul>
</div>
</div>