Click on the My Teams Tab on the Left Navigation toolbar.
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Scroll down to “Edit Your Team Information”. Click on the Push/Pull Page Header Color box where you can change the background to any color by choosing a color from the color wheel or by entering the RGB value of the closest match and click on Choose and then click on Save Team Information.
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You will see a success message at the top of your Dashboard and you will notice that the Logo in the left top corner now has a background color.
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This background color along with your company's logo will show on the following pages:
Push/Pull Request Links
Push/Pull email notifications
Password resets
TFA email and link
Team Invite Email to users
Password change email notification when Admin changes user password
Personal URL page
Dashboard (upper left corner)
Dashboard Two-Step Authentication Login
Change Email Confirmation page
Successful and Failed SMTP notification