Custom CSS lets you adjust public event pages beyond HeySummit's standard theme and branding controls. Use the Theme Editor and built-in Branding & Content options first, then use Custom CSS only when you can test and maintain the code yourself.
Before you add code
Confirm that the event's plan includes Custom CSS. If the field is disabled, the event owner can review the subscription under My Account > Billing. Previously saved CSS stays stored but does not load on event pages while the feature is unavailable.
Keep a copy of the last working CSS and make one small change at a time.
Remember that HeySummit cannot provide technical support for custom CSS code or changes caused by it.
Add or update Custom CSS
From the event dashboard, go to Event Setup > Settings.
Find Branding & Content and select Update.
In the Custom CSS section, paste or edit your CSS.
Select Save.
Check the affected public pages in a signed-out browser on desktop and mobile before relying on the change.
Recover from a styling problem
Return to the Custom CSS field, remove or revert the latest code, and save again. The broader Reset Event Branding action also removes Custom CSS and resets branding colours, so use it only when you intend to reset those other branding changes too.