Currently I have an issue where a border-top (underneath a header) is being cut short, just where the list indenting starts on the text underneath. I want the border-top to go all the way to the left edge of the sidebar. Is there a way of styling the border to ignore list indenting? I'm doing this in WordPress, which is making this a lot more difficult than it should be...
And your code is ...?
By default, a list's indention is caused by padding on the list container, i.e. the ul or ol element. Which side has the padding depends on the the text direction, ltr or rtl.
If your border is on the list container, it should span the entire width. If it doesn't, you've done something else and we can't help you without seeing what you've done; the html and css codes.