Antimatter Theme: Subpages

Complete beginner here. I am using the antimatter theme (with slight customizations) enable through theme streams/inheritance and want to know how to get drop downs for subpages similar to the “Layouts” in the OER Skeleton

The OER demo is using Gantry5 theme framework to achieve those different layouts -

However, you can do similar with any Grav theme by creating a variety of top-level page templates. For example, Antimatter already has a few like default.html.twig, blog.html.twig, etc. Just create a new one for each ‘layout’ you want to create…

Regarding dropdowns, Antimatter already supports that, just enable it in the Antimatter theme configuration.

A perfect. I was trying this but was activating the drop down in the wrong file (have sorted it out now!) Thanks for the quick response!