Change design of tabs

Description

Improved course tabs and unit tabs design. Implemented designs with Google apps reference.

Changed following things in both tabs

  • Background color light theme

  • Text color theme color

  • Removed underline

  • Hover color light gray

Visuals
<img width="446" alt="Screenshot 2020-11-15 at 1 40 10 PM" src="https://user-images.githubusercontent.com/20799038/99180125-991f6700-2749-11eb-93ac-1a89e862957f.png">
<img width="1196" alt="Screenshot 2020-11-15 at 1 40 23 PM" src="https://user-images.githubusercontent.com/20799038/99180128-9ae92a80-2749-11eb-8f0b-50abe52106d5.png">

Won't Do

Assignee

Marco Morales

Reporter

Open Source Pull Request Bot

Labels

Contributor Name

None

Repo

edx/frontend-app-learning

Customer

None

Epic Link

None

OSCM Assignee

None

Platform Map Area (Levels 1 &amp; 2)

None

Platform Map Area (Levels 3 &amp; 4)

None

Blended Hour Utilization Percentage

None

edX Theme

None

edX Squad

None

Github Lines Added

13

Github Lines Deleted

19

Priority

Unset