Hi - I am having the same problem and the only way I seem to be able to make style changes to the Woo Commerce end of the site is to copy and paste all the woocommerce.css style into the Twenty Thirteen Style sheet of the website. Then at the bottom of the woocommerce.css within that style sheet I make the changes to the necessary elements so that they come after their initial styling and so override. But as is stated in this debate "what happens when the Twenty Thirteen Theme is updated"
So here is what I have tried:
Copied and pasted the woocommerce.css from the plugin/assets/woocommerce.css styling code and pasted it into my Twenty Thirteen Theme/style.css
Then I tried to implement changes using my Twenty Thirteen Child Theme/style.css. When I tried this no changes were implemented.
Then I tried pasting the woocommerce.css code into the Twenty Thirteen Child/Style.css as well as leaving the code in the Twenty Thirteen/Style.css file
Again nothing happened when I implemented some style changes.
Then I went directly into the TwentyThirteenTheme/style.css and directly under the block of minified, (if that is a word) css code for woocommerce (which I pasted earlier) I effected some changes to the style and they seem to be working.
So my big issue is this. Do I keep going and maybe make a back-up copy of my main style.css file and store it in the TwentyThirteenChild Theme folder so that when updates to the Twenty Thirteen Theme are effected I just need to copy and the necessary code back into the Twenty Thirteen/Style.css file.
I understand that this is not the simplest way of doing things, but I have tried lots of other suggestions I seen on forums and none of them worked.
Also: SplashingPixels made this statement earlier:
"Every theme is different so you have to first determine what styles file you can use which won't be erased on the theme update. Good themes will have a way for you to do that.
Then you would paste the WC styles into that file."
Does anybody know how to determine which files will not be erased on theme updates?
Thanks for any help that might be forthcoming.