First, you need to activate Fundlify App Extension and Page / Product templates on your current theme.

From your campaign page editor click on Customize button, this will take you to your theme’s customizer and loads your campaign template (fundlify-page)

From left pane of your customizer

Click on + Add block and select Fundlify Page

You can now customize your campaign page.

Note that you can only add sections to either the Header or Footer sections, but not to the Template section, this is because the Template section is dedicated to your campaign page.

Your theme customizer is pretty straight forward; You can fully customize the look and feel of your Fundlify campaign page and widget — including title placement, font sizes, colors, background colors, padding, progress bar styling, button styling, and reward card appearance — all through adjustable sliders and hex color pickers, without touching code.