CSS-Content/Sidebars follow Background

Question

I am using Drupal-Zen Theme. What would I need to do if I want ALL the website content(like sidebars) to follow the background when the Browser size is adjusted?

Example: Say I have a block with the letter C and I have a background image with the letter C. They both look like one letter when the browser resolutions is 980x1120 (example). But I want the block to expand with the background so C looks like the same no matter if the resolution was 180x320 or 2400x3200 for example.

Answer 1

You should be able to achieve this result using background size:

#my_container {
    background-size: 100% auto;
}