Disable all ios customizations

We have created a big app in ionic 3. We targeted a desktop browser first, but now that we are testing on an iPad, it’s actually a disaster. The menu’s css is forced to a white background, and some of the menu items are invisible. The sidemenu is unswipable, and lots of other small UI issues.

Can I force the css to somehow ignore its ios tweaks, or is iOS’s Safari really that different from MacOS’ Safari?

Note that we are not using Cordova (yet)