Setting base font sizes for hybrid app

We are creating a hybrid app using Ionic2, and it needs to present well on iOS, Android and web. How do we control the base font size so the app presents well on both Android and Web?

Ionic2 gives us SASS variables to set the base font size. These are:
$font-size-base
$font-size-ios-base
$font-size-md-base

iOS is fine - we set $font-size-ios-base to 12px, and the iOS app presents nicely. However, it appears that $font-size-md-base controls the base size for both Android and Web. Is there some other built-in way that we can set these so that the Web version will have a larger base size than the Android version?

Please forgive the question if it is obvious - I am new to Ionic, CSS, SASS and HTML.

This is because the default “core” mode that ionic uses on the web is based on what we use for android.
So when you change that, it modifies both.

Though your really shouldn’t need to modify these values.
Each pixel value have been set to best fit the platform they meant for.