How to write the position property correctly?

Question

css

There are 3 div blocks, I assigned them a certain height and width and there is an img, there is a picture in it, I want to place 3 div blocks inside the picture, I write it like this: img {position: relative} and div blocks position absolute, left: 0, top: 0, but they appear in the upper left corner, i.e. they are positioned relative to the body, I don't understand why?

Answer 1

img is a photo and it cannot be a parent for anyone
, but if img wraps a div and makes it a parent, i.e. relative, in this case the absolute elements will be exactly inside it