Change Gmail theme. You will see Gmail default theme after open Gmail mail inbox. But Gmail have a more themes. You can change theme in Gmail. Learn how to change your theme on Gmail.
1. Open Google website, log in Gmail mail account using email address and password. Open Gmail mail inbox page.
2. Click right sight settings icon then you will see few buttons. Click Themes button from this lists.

3. You will see Gmail settings page with few themes. Scroll down and click up to any theme which you like. You will see your Gmail theme will change.

Using the same you can choose any theme for your Gmail mail interface.