title: Make DIV max-height equal to `window height - 100px`
body: <p>There is a way to set <code>max-height</code> in <code>%</code>, but is here any way  to set DIV max-height, so it would be 100px smaller than window height with only CSS?</p>
  
  <p>It must not be a fixed layout, user must be able to scroll page vertically, but DIV always should be resized to <code>window height - 100px</code>. Is this possible, or will I have to use JS for that?</p>