How did they make this website?

One of my clients has a website I am rebuilding. They have a second site that will be there next project and I want to line it up. I want to model it after
calm.com
Which is the best presentation of the type of website it is. Does anyone know how to make that full page animated video style website?

Is there a plug and play platform I can use or do I need to build from scratch with flash?

That site is not build with flash, it is just simple HTML5 code...
Search on google for some HTML 5 video tutorials, full screen videos etc... and you can do that with no problem...
Cheers

Thanks Buddy!

I just needed to know what to google, I am all set now.

:O in the future you can look at the source code and usually it will tell you all you need to know about how the site is made, for instance on line 123 through 128 where it has the tags, div#calm-video-wrap div#calm-video-outer video#calm-video-vid.

It's a fullscreen video background theme, you'll find them at Themeforest.
You can use a Wordpress template and finish that site in under 2 hours.