Sorry..forgot the images. This will depend on where and what as images in the theme will depend on how they are being added. But to give you a direction, in the style.css is this batch of empty classes, ready for styling around line 1424:
/* 28 Images
-------------------------------------------------------------- */
img.attachment-post-thumbnail,
img.wp-post-image,
img.attachment-thumbnail,
img.attachment-medium,
img.attachment-large,
img.attachment-full {}
You can separate those if you want to target specific ones or all. You can even create your own class and when you insert images into a page or post, add your class to the
tag.
Here is more about images:
http://codex.wordpress.org/Styling_Images_in_Posts_and_Pages