diff --git a/cmd/ninja/cmd/theme.go b/cmd/ninja/cmd/theme.go
index 437c67f..af7f946 100644
--- a/cmd/ninja/cmd/theme.go
+++ b/cmd/ninja/cmd/theme.go
@@ -115,7 +115,7 @@ the rest of the CLI.`,
 					return fmt.Errorf("create %s: %w", screenshotsDir, err)
 				}
 				n := 0
-				for _, pageSlug := range strings.Split(pages, ",") {
+				for pageSlug := range strings.SplitSeq(pages, ",") {
 					pageSlug = strings.TrimSpace(pageSlug)
 					if pageSlug == "" {
 						continue
@@ -176,7 +176,7 @@ func parseModes(modes string) ([]string, error) {
 		return []string{""}, nil
 	}
 	var out []string
-	for _, m := range strings.Split(modes, ",") {
+	for m := range strings.SplitSeq(modes, ",") {
 		m = strings.TrimSpace(m)
 		if m != "light" && m != "dark" {
 			return nil, fmt.Errorf("--modes: %q is not a valid mode (want light or dark)", m)