How to make modern landing pages?

Question

Layout

I'm interested in how to properly layout the decorative elements that are now shoved into almost every landing page. As well as how to make up illustrations (screenshots). Either through background or just through img.
I am also interested in how to make at least some kind of adaptability in such projects, in standard landing pages you can write adaptability in 10 minutes, but here there is no idea how at all.

Answer 1

Either through background or just through img

img is an integral part of the content that is critical for the user, e.g. product picture.
background is a part of the interface: icons, block backgrounds, special effects, everything related to design;