Hello,
I am mobile/backend developer for years now, and I decided to enter the pro theme to finish one design. So I beg for your help 
I do have css/html/php experience, so I kindly ask to point me in to the right direction.
https://gyazo.com/c2bda2ef14ecc9ff4687397d65844ae4
I created the header that has hero image and the buttons like in screenshot on the bottom part of the header. Now I want to create my first section.
1: how to approach to border that will be solid, but on top only next to the corner
2: how to make background waves that will be entering the top section
(for the border, is to make content area with border bottom, left, right solid, and html content. But I dont know how to approach the top border.
(for the background my idea is to make css curve in the first section and then make full blue background in the next section, that way it would connect. But I am open to learn better approach)
Ty, and I vouch to help the others once I get versed in pro theme