frontend: NodeDetails: adjust styles to use new theme tokens

Signed-off-by: Oleksandr Dubenko <[email protected]>

Author: sniok

frontend/src/components/node/Details.tsx

@@ -305,8 +305,9 @@ function ChartsSection(props: ChartsSectionProps) {
       >
         <Grid item xs={4}>
           <Paper
+            variant="outlined"
             sx={theme => ({
-              background: theme.palette.squareButton.background,
+              background: theme.palette.background.muted,
               padding: theme.spacing(2),
               height: '100%',
               maxWidth: '300px',