one of three, exclusive
mounted as radio-button
why it looks like this
The phone's radio button: a 32 px ring with a 3 px stroke and a 16 px dot — exactly half — both in the foreground colour, on a transparent fill. Held down it takes KvadrantColors.checkBoxPressed and KvadrantColors.checkBoxPressedBorder — not the accent.
Read it: kvadrant-core/src/commonMain/kotlin/io/github/youndie/kvadrant/components/KvadrantSelection.kt · the full signature and every parameter