In reaction to Baymard’s post ‘avoiding inline labels in mobile forms‘ there is a recent pattern I have been seeing, at least have seen so far on 2 desktop sites:
Clicking an empty form moves the inline label to above textfield, and resizes label
It seems this patterns disregards Baymard recommendations, but still works for me. Still have to test if & how they did it on mobile. The only issue I can imagine is if the textfield is on top of the viewport. Otherwise shouldn’t seem a problem CSS wise.