[fix] migrate localfont to hosted font

pages/500.tsx

@@ -14,13 +14,11 @@ export default function ServerErrorPage() {
     <Page>
       <NavBar />
       <ContentContainer>
-        <h2 className={`my-5 flex justify-center text-2xl font-bold font-fang-zheng-xiao-biao-song`}>
-          {"INVALID OPERATION"}
-        </h2>
+        <h2 className={`my-5 flex justify-center text-2xl font-bold caption-font`}>{"INVALID OPERATION"}</h2>
         <Separator />
         <div className="my-5 flex flex-col justify-center">
           <MdOutlineDangerous className="mx-auto my-4" size={"6em"} />
-          <p className={`font-source-serif-screen mx-auto my-3 text-center text-xl`}>
+          <p className={`content-font mx-auto my-3 text-center text-xl`}>
             {"Something went wrong. Please try again later."}
           </p>
           <div className="my-5 flex justify-center">