How to change tabs look

Hi guys,
Do you know how to make this kind of tab view :

When you click the tab there like an arrow pointing down.

Thank you

Here is my site Read-Only: LINK
(how to share your site Read-Only link)

Design looks nice:
I dunno exactly how can be done, But it will be a fun to solve this

Anyway some suggestions:

  1. Maybe ask designer to simplify the design (best it will save ton of time)
  2. Create a div arrow pointing & move it with animation (on tab change animation)

Share read-only link, so I can help better