fix demo

Author: oliviertassinari

docs/src/pages/components/click-away-listener/PortalClickAway.js

@@ -7,8 +7,8 @@ const useStyles = makeStyles((theme) => ({
   dropdown: {
     position: 'fixed',
     width: 200,
-    top: 0,
-    left: 0,
+    top: '50%',
+    left: '50%',
     transform: 'translate(-50%, -50%)',
     border: '1px solid',
     padding: theme.spacing(1),

docs/src/pages/components/click-away-listener/PortalClickAway.tsx

@@ -8,8 +8,8 @@ const useStyles = makeStyles((theme: Theme) =>
     dropdown: {
       position: 'fixed',
       width: 200,
-      top: 0,
-      left: 0,
+      top: '50%',
+      left: '50%',
       transform: 'translate(-50%, -50%)',
       border: '1px solid',
       padding: theme.spacing(1),