How to make animation-delay work consistently?

Question

css

Good afternoon, colleagues.
I have a question about setting animation playback for
SUBJECT blocks:
There are several divs for which animation should SEQUENTIALLY, with a delay. The animation goes on in an endless loop.
Those. first, the animation should play in the first block, then in the second, then in the third, then all in a circle. With a delay of a couple of seconds.
https://codepen.io/emelyanova/pen/PRqrwR
PROBLEM:
The delay only works on the first play.
What am I doing wrong?
Thank you in advance for your help!

Answer 1

In general, dear colleagues, the whole point is in the proportion of animation duration, delay and time function. Play here

Answer 2

https://codepen.io/topicstarter/pen/KodPZB seems to be and then it seems to be not! seems to be at least partially