#717: Column with margin goes out of stage on mobile viewport

Author: omiroshnichenko

app/code/Magento/PageBuilder/view/adminhtml/web/css/source/content-type/column-group/_mobile.less

@@ -10,7 +10,7 @@
     .pagebuilder-content-type {
         .pagebuilder-column-group {
             > .element-children {
-                display: block;
+                flex-wrap: wrap;
             }
         }