diff --git a/ui/src/lib/color-contrast.ts b/ui/src/lib/color-contrast.ts
index 70b2296a31..a7eb692a2c 100644
--- a/ui/src/lib/color-contrast.ts
+++ b/ui/src/lib/color-contrast.ts
@@ -68,8 +68,18 @@ function composite(
   };
 }
 
-const TEXT_LIGHT = "#f8fafc";
-const TEXT_DARK = "#111827";
+/**
+ * Shared readable-text pair (slate-50 / gray-900) for "pick light or dark
+ * text over an arbitrary background" logic. Byte-identical values were
+ * previously duplicated in lib/worktree-branding.ts (DECISION-SHEET.md A2);
+ * this is the single source. NOT the same thing as ThemeContext.tsx's
+ * <meta theme-color> pair (#18181b/#ffffff), which stays separate.
+ */
+export const READABLE_TEXT_LIGHT = "#f8fafc";
+export const READABLE_TEXT_DARK = "#111827";
+
+const TEXT_LIGHT = READABLE_TEXT_LIGHT;
+const TEXT_DARK = READABLE_TEXT_DARK;
 
 /**
  * Pick a readable text color for a solid background.
diff --git a/ui/src/lib/worktree-branding.ts b/ui/src/lib/worktree-branding.ts
index 6f6d8dc4e4..d4781ded4d 100644
--- a/ui/src/lib/worktree-branding.ts
+++ b/ui/src/lib/worktree-branding.ts
@@ -1,3 +1,5 @@
+import { READABLE_TEXT_LIGHT, READABLE_TEXT_DARK } from "./color-contrast";
+
 export type WorktreeUiBranding = {
   enabled: true;
   name: string;
@@ -46,7 +48,7 @@ function pickReadableTextColor(background: string): string {
     (0.0722 * relativeLuminanceChannel(b));
   const whiteContrast = 1.05 / (luminance + 0.05);
   const blackContrast = (luminance + 0.05) / 0.05;
-  return whiteContrast >= blackContrast ? "#f8fafc" : "#111827";
+  return whiteContrast >= blackContrast ? READABLE_TEXT_LIGHT : READABLE_TEXT_DARK;
 }
 
 export function getWorktreeUiBranding(): WorktreeUiBranding | null {