diff --git a/internal/theme/theme.go b/internal/theme/theme.go
index d33a2a5..0309f13 100644
--- a/internal/theme/theme.go
+++ b/internal/theme/theme.go
@@ -3,15 +3,15 @@ package theme
 import "github.com/koki-develop/gh-grass/internal/github"
 
 var (
-	_ = Register("dark", "#161B22", "#0E4429", "#006D32", "#26A641", "#39D353")
-	_ = Register("light", "#EBEDF0", "#9BE9A8", "#40C463", "#30A14E", "#216E39")
+	_ = register("dark", "#161B22", "#0E4429", "#006D32", "#26A641", "#39D353")
+	_ = register("light", "#EBEDF0", "#9BE9A8", "#40C463", "#30A14E", "#216E39")
 )
 
 type Theme map[github.ContributionLevel]string
 
 var registry = map[string]Theme{}
 
-func Register(name, none, first, second, third, fourth string) Theme {
+func register(name, none, first, second, third, fourth string) Theme {
 	t := Theme{
 		github.ContributionLevelNone:           none,
 		github.ContributionLevelFirstQuartile:  first,