css use values of certain propreties to determine others code example

Example 1: css custom properties

/* create */
:root {
	--variable-name: variable-property;
}
/* use */
selector {
	property: var(--variable-name);
}

Example 2: css variables

:root {
  --background-color: #333;
  --text-color: #fff;
}
body {
  background-color: var(--background-color);
  color: var(--text-color);
}