OVERVIEW
This article describes how to change the theme and layout on your Microsoft Teams application.
How to change the theme and layout on your MS Teams App
Step 1. In MS Teams, select the three dots next to your profile picture on the top right corner.
Step 2. From the drop-down menu, select "Settings".
Step 3. In the "Settings" window, select the "General" tab from the left hand navigation menu to access the theme and layout settings.