Step 1: Head to your promotions and under actions hit edit design
Step 2: Highlight the are you'd like to edit and hit the custom code button. Once clicked the selected area will display the code for that section.
Step 3: You can also head to the custom section at the top of the design canvas that separates the tab and overlay code for you. Make sure you hit "override" on off switch to make sure this code is pushed!
Friendly Note: We keep Justuno an open platform for those users who are technically savvy enough to implement the changes they want, we do not offer custom coding for clients.