Something strange is happening with a fixed position element in Chrome. It is still scrolling with the page even though it should be fixed. To better understand the issue, you can view it on the live site
In Firefox and even IE, the "Block 1 Block 2 Block 3" text behaves correctly, sticking to the top of the screen as expected. However, in Chrome, it jumps to its fixed position prematurely and continues to scroll despite being set as fixed. It's truly one of the most bizarre things I've ever encountered.