diff --git a/src/admin/theme.test.ts b/src/admin/theme.test.ts
index a0b32c7..7b7f6cc 100644
--- a/src/admin/theme.test.ts
+++ b/src/admin/theme.test.ts
@@ -1,6 +1,23 @@
 import { describe, it, expect } from "vitest";
 import { theme } from "./theme";
 
+/** Minimal palette shape used by the colorSchemes assertions below. */
+interface SchemesPalette {
+  primary: { main: string };
+  background: { default: string; paper: string };
+  error: { main: string };
+  success: { main: string };
+}
+interface ColorScheme {
+  palette: SchemesPalette;
+}
+interface ThemeWithColorSchemes {
+  colorSchemes: { light: ColorScheme; dark: ColorScheme };
+}
+
+/** Single typed assertion so every `colorSchemes.*` access below is checked. */
+const themedSchemes = (theme as unknown as ThemeWithColorSchemes).colorSchemes;
+
 describe("MUI theme", () => {
   it("uses the brand fonts", () => {
     expect(theme.typography.fontFamily).toContain("Plus Jakarta Sans");
@@ -8,18 +25,18 @@ describe("MUI theme", () => {
   });
 
   it("maps the brand red per color scheme", () => {
-    expect(theme.colorSchemes.light.palette.primary.main).toBe("#c73030");
-    expect(theme.colorSchemes.dark.palette.primary.main).toBe("#d63031");
+    expect(themedSchemes.light.palette.primary.main).toBe("#c73030");
+    expect(themedSchemes.dark.palette.primary.main).toBe("#d63031");
   });
 
   it("maps the refreshed light canvas + paper", () => {
-    expect(theme.colorSchemes.light.palette.background.default).toBe("#f4f3f1");
-    expect(theme.colorSchemes.light.palette.background.paper).toBe("#ffffff");
+    expect(themedSchemes.light.palette.background.default).toBe("#f4f3f1");
+    expect(themedSchemes.light.palette.background.paper).toBe("#ffffff");
   });
 
   it("maps semantic colors per scheme", () => {
-    expect(theme.colorSchemes.light.palette.error.main).toBe("#b91c1c");
-    expect(theme.colorSchemes.dark.palette.success.main).toBe("#22c55e");
+    expect(themedSchemes.light.palette.error.main).toBe("#b91c1c");
+    expect(themedSchemes.dark.palette.success.main).toBe("#22c55e");
   });
 
   it("uses the base radius of 10", () => {