Change various background colors blog page and posts

I can not figure out how to use a different background color other than white for my view author info. I don’t like white and the text color of page is white so text is not visible. Also i have a picture widget at bottom of side bar and where the title goes the background is white which also leves text not visible.
Also, the background f read more area is also white and want to change it.
http://irontrainer.co/iron-blog/
Like to be able to change tags backgound on post page
http://irontrainer.co/las-vegas-iron-trainer/ author info here also
Basically all the white backgrounds. Are these changeable without a css code? Also is text in these areas changeable without css code.
Thank you