[moritzwarhier]

The modals and stickies are there for marketing reasons obviously, and given sufficient budget, they will be designed responsively as well (not saying this makes the experience better).

Comments on this except for the one mentioning vh honestly don't reflect current web dev + design reality anymore. And even then, you probably want to consider dvh vs vh depending on what you are doing (of course you don't want your whole layout to shift because of the on-screen keyboard either)

But they reflect mistakes that bad designers make all the time.

When I was doing web dev, it was mostly like this: there are two mock-ups, one for 1920x1080 and one for the viewport of the latest iPhone or sth similar.

The rest was up to the skill and interpretation of the developer.

To a degree, this is a sane approach, because as a web dev, it is your job to understand this and tweak things to look good regardless of DPR and viewport size in CSS pixels.

If you want to design the perfect landing page, you will encounter all kinds of tradeoffs depending on viewport dimensions. But it can be fun to tackle this problem.