shadcn has a set of roles — --primary, --card, --popover, --border, and so on. A binding decides which of Tonex's generated colors a role points at. Because it points at a generated color rather than a fixed value, a bound role stays automatic: change the seed, variant, or contrast and the role updates with the system.
Changing a binding
Each role has a binding you can repoint. If the default mapping doesn't fit your visual hierarchy — say you want --popover on a different surface than --card — rebind it to the generated color you'd rather it track. It keeps updating from there.
Bindings are per mode, so light and dark can point the same role at different colors.
Bindings vs overrides
A binding is symbolic: the role tracks a generated color. A role override is literal: the role is pinned to an exact value and stops tracking. An override beats a binding. Use a binding when you want a mapping that's different but still automatic, and an override when you need one exact color.
Defaults
A role's starting binding comes from the active preset. Switching the preset replaces your bindings but keeps your overrides; switching the scheme variant keeps both, and bound roles update to the new colors.