Hi Jay,
Please try the following steps:
1. Login to the Mobility Master.
2. In the Managed Network node hierarchy, navigate to the Configuration > Roles & Policies page.
3. Select a role and click Show Advanced View in Roles > <rolename> table.
4. Click Captive Portal. Click Internal captive portal with authentication option.
Refer to screenshot CP
5. Click on the Thumbnail to edit the Templates. You can edit the logo, Box Color, Text Color, and Button Color. Click Preview the view the changes.
Refer to screenshot CP1
6. Click Submit to save the changes.