separate bg-col and wdit-col and add opacity inside of the edit one

src/client/js/components/PageEditor/GridEditModal.jsx

@@ -63,7 +63,7 @@ export default class GridEditModal extends React.PureComponent {
               </div>
             </div>
           </div>
-          <div className="container position-relative edit-wrapper p-4">
+          <div className="container position-relative p-4">
             <div className="row">
               <div className="col-3">
                 <h5>Phone</h5>

src/client/styles/scss/_on-edit.scss

@@ -317,12 +317,13 @@ body.on-edit {
 }
 
 // [border-color:TODO support dark mode by GW-3037]
-.grid-bg-col,
-.grid-editable-col {
+.grid-bg-col {
   border-right: 5px solid white;
   border-left: 5px solid white;
 }
 
-.edit-wrapper {
+.grid-editable-col {
+  border-right: 5px solid white;
+  border-left: 5px solid white;
   opacity: 0.5;
 }