If you would like to switch your platform's Light theme to Black or Navy mode, you can do so by tapping on your Menu tab 
at the bottom-right corner of your screen.
In the Trading 212 Web app, click on your email address at the top right corner of the screen to access your Account Settings Menu.
Click on Settings 
and tap on the [Theme] tab to switch between the Light, Black, Navy and 'System' theme options.
