diff --git a/packages/utils/src/color.test.ts b/packages/utils/src/color.test.ts
index 35427288a..113ddd7f6 100644
--- a/packages/utils/src/color.test.ts
+++ b/packages/utils/src/color.test.ts
@@ -21,6 +21,11 @@ describe("rgbaStringToHex", () => {
 	it("converts arbitrary mid-range color", () => {
 		expect(rgbaStringToHex("rgb(128, 64, 200)")).toBe("#8040c8");
 	});
+
+	it("preserves 6-digit hex colors", () => {
+		expect(rgbaStringToHex("#F1F5F9")).toBe("#f1f5f9");
+		expect(rgbaStringToHex("#0F172A")).toBe("#0f172a");
+	});
 });
 
 describe("parseColorString", () => {
diff --git a/packages/utils/src/color.ts b/packages/utils/src/color.ts
index b86313cbc..57a7ab911 100644
--- a/packages/utils/src/color.ts
+++ b/packages/utils/src/color.ts
@@ -2,10 +2,17 @@ import type { ColorResult } from "@uiw/color-convert";
 import { hsvaToHex, rgbaStringToHsva } from "@uiw/color-convert";
 
 export function rgbaStringToHex(rgba: string): string {
+	const color = parseColorString(rgba);
+	if (color) return `#${toHexComponent(color.r)}${toHexComponent(color.g)}${toHexComponent(color.b)}`;
+
 	const hsva = rgbaStringToHsva(rgba);
 	return hsvaToHex(hsva);
 }
 
+function toHexComponent(value: number): string {
+	return Math.max(0, Math.min(255, value)).toString(16).padStart(2, "0");
+}
+
 export function parseColorString(value: string): ColorResult["rgba"] | null {
 	const trimmed = value.trim();