If you have some Custom CSS that you need to apply for your SharePoint or Office365 site, you can easily do this using the Custom CSS feature in the Site Branding & Customization Tool by following these steps.


Step 1: Open the Site Customization Tool


Go to Site Settings



Then to ShortPoint Dashboard



Click the Theme Builder tile:



Then Click on the Customize my site button



Step 2: Apply your Custom CSS

Once the branding & customization tool is opened, Navigate into Utilities 



Then to Custom CSS:



paste your CSS Customizations into the Custom CSS Field, and click Apply:



And of course, do not forget to Publish your changes in order to make them available for your site visitors: