improve mobile display

Author: oliviertassinari

docs/src/modules/components/Demo.js

@@ -54,12 +54,15 @@ const styles = theme => ({
     position: 'relative',
     outline: 0,
     margin: 'auto',
-    borderRadius: theme.shape.borderRadius,
     display: 'flex',
     justifyContent: 'center',
+    borderLeftWidth: 0,
+    borderRightWidth: 0,
     border: `1px solid ${fade(theme.palette.action.active, 0.12)}`,
-    padding: theme.spacing(2),
     [theme.breakpoints.up('sm')]: {
+      borderRadius: theme.shape.borderRadius,
+      borderLeftWidth: 1,
+      borderRightWidth: 1,
       padding: theme.spacing(3),
     },
   },