Dealing with empty and undefined title

quartz.config.ts

@@ -23,7 +23,7 @@ const config: QuartzConfig = {
       fontOrigin: "googleFonts",
       cdnCaching: true,
       typography: {
-        title: "Playwrite US Trad",
+        title: "Playwrite DK Loopet",
         header: "Schibsted Grotesk",
         body: "Source Sans Pro",
         code: "IBM Plex Mono",

quartz/util/theme.ts

@@ -25,7 +25,7 @@ export type FontSpecification =
 
 export interface Theme {
   typography: {
-    title: FontSpecification | undefined
+    title?: FontSpecification
     header: FontSpecification
     body: FontSpecification
     code: FontSpecification