Someone asked on this group https://www.facebook.com/groups/webdeveloperitaliani/permalink/1012941225452415/ how to create a transition akin to the one on the Goldman Sachs homepage (http://www.goldmansachs.com/).
Here's a pure-css solution (not general nor super elegant but I only had 20min to spare).
A Pen by Claudio Brandolino on CodePen.