meaning of text/background colors of Theme

[herosz]

Hy!
I definitely don't understand the first four text/background sample of theme colors. Let's note these colors from their lines by 1, 2, 3 and 4.
the color of 1 (gold in my case) appears in the second sample image as Text ← Why not in the first image?
the color of 2 (black) appears in the first sample image as Text
in both sample image color 2 also appears in a circle ← What means these circles?
Edit Theme Colors.png


color 3 and 4 appear as background
If I want the use these colors e.g. in the body text and hold the mouse over these Theme colors I got Background 1 for the first color as in second attached image ← Now color 1 became background although the background colors were the colors 3 and 4, what happens??
background1.png

please someone explain it or guide me to some documentation