How can I make my background-color fill all my content, even with horizontal scrolling?

Question

I'm using an <ol> to show a code snippet with line numbers. Since I'm showing program code, I disable wrapping (and enable indentation) by setting white-space: pre on li, which means an li's content can extend past the right margin and cause the page to have a horizontal scroll bar. So far so good.

The problem comes when I want to set background colors on some of the lis to call out particular lines of code. I can set background-color on the li, but the color only extends to the right margin of the page; in fact, the last 10 pixels or so of text (an amount equal to the body's right margin) has no background color. And if I scroll horizontally, it's even worse: the background color scrolls left off the page. The background-color is only one browser-width wide (minus the page margins).

Here's a fiddle illustrating the problem. If you scroll right, I want the background to be blue for as far as there's text.

How can I get the background-color to fill the full width of the content, even if the page scrolls horizontally?

Answer 1

You can "shrink-wrap" each li's content with a combination of float and clear, as in this answer.

li {
    white-space: pre;
    background: blue;
    float:left;
    clear:left;
    min-width:100%;
}

The last line is from koala_dev's answer. It forces shorter-content elements to have full-width background.

Fiddle