I've been racking my brain for the past couple of days trying to solve this. Essentially, I am working on a one-page layout where the first block occupies the entire width and height of the screen, while the second block needs to be relative to the first.
For example, please take a look at this site:
<body>
<div id = "block1">
This is block 1 that fills the entire screen width and height.
</div>
<div id="block2">
Block 2 is positioned relative to block 1.
</div>
</body>