Let’s say you would like to add a third-party tracking script, such as Google Analytics to your Marketo landing page. This is possible via the Marketo UI. More generally, you can add any custom code (HTML, CSS, JavaScript) to your Marketo landing by following the instructions below.
1. Select your landing page and click on Edit Draft.
2. Drag in the HTML element.
3. Enter your custom code, and click Save.