Edit the theme of your site
By clicking the Theme option you will be redirected to the page where you can edit your theme.
On the the top you have two tabs: Dashboard and Authentication, you can switch between them to customize the pages.
To change the colours click the element you want to change and a box with a colour palette will appear, select your desired colour and click Close.
Some elements are related, that means that when you change the colour for one element, other elements will change their colour.
For instance: by changing the App bar colour (the one where it says Dashboard), the footer bar in the linked email will change colour also.
After you are done editing, press Save in the bottom left corner. If you want to revert to default settings, press Restore to default and Save.
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