change captcha inputbox theme

src/component/Common/Captcha/DefaultCaptcha.tsx

@@ -41,7 +41,7 @@ const DefaultCaptcha = ({ onStateChange, generation, noLabel, ...rest }: Default
           pr: 0.5,
         },
       }}
-      variant={"filled"}
+      variant={"standard"}
       label={noLabel ? undefined : t("login.captcha")}
       onChange={(e) => setCaptcha(e.target.value)}
       value={captcha}