Mirotone uses variables, they are split in two groups, initial and derived variables. All those values are in the src/foundation-core.css. You can override the foundation-core before importing Mirotone or with ruling the CSS. For now please use the DevTools to check the full list of created variables.
Those variables are defined by literal value.
Those variables are calculated based on a initial variable created.
--space-small: calc(var(--space-xsmall) * 2)