Not displaying correctly in Instagram browser on android


I have a strange issue where my site won’t display correctly on the in-app browser on Instagram. i.e When people click on a link from Instagram to open the site.

Android Chrome: (correct)

Instagram in-app browser:

The problem can be seen in the way that the words ‘mysteries’ overlaps ‘of’ and ‘Trust’ overlaps ‘Sangharakshita’ in the header logo.

The problem does not persist on iOS, and it also does not persist on other in-app browsers (e.g Twitter).
For reference, here’s the Twitter in-app browser (displaying correctly)

Does anyone know what this could be due to? The only thing I can think is it’s something to do with where the viewport top or bottom is being set… Not sure though.

Many thanks in advance.

Here is my site Read-Only: LINK