CSS Element State Button Fix

packages/builder/src/components/userInterface/FlatButtonGroup.svelte

@@ -28,6 +28,7 @@
     onChange(val)
   }
 
+
   const checkSelected = val =>
     isMultiSelect ? value.includes(val) : value === val
 
@@ -37,7 +38,7 @@
   {#each buttonProps as props}
     <div class="button-container">
       <FlatButton
-        selected={checkSelected(props.value)}
+        selected={isMultiSelect ? value.includes(props.value) : value === props.value}
         onClick={onButtonClicked}
         {...props} />
     </div>