Layout problems when using video

I'm having some layout issues with a design I'm doing here: http://ift.tt/1IRrQXk

I'm trying to replicate the video/search box layout on Airbnb's homepage. In fact, I'm using their video in my page at the moment. The problems I'm having are screengrabbed here. But basically they are:

1. How do I get the purple box with the form to overlap the video or at least appear without a gap?


2. How do I keep the video from getting so tall on desktop browsers that the purple box and text below gets pushed below the fold?

I've experimented with the CSS and HTML, trying to improve what I have, but what you see now is the best I can get. Any pointers to push this in the right direction would be welcome.

Thanks! Russell