After adding a repeatable block - speakers, sponsors, schedules - any style edits you make will affect all of the included elements consistently. Need to change the border from a square to a circle? You only have to make this change once.
Luckily this is why the repeatable was built, so the steps to style this are quick and easy.
1. Click on the Repeatable Block within the Layout tab on the toolbar.
This opens the elements within the block. Click on the repeatable element - Speaker, Sponsor, etc. This opens the master level of the repeatable, which is the group of elements that repeat as a pattern.
2. Once you're in the master repeatable level, we can start editing and styling all of the elements and top-level designs.