fix/Use width rather than flex basis

Author: LewisYoul

app/views/layouts/application.html.erb

@@ -42,7 +42,7 @@
           <%= render 'shared/sidebar' %>
         </div>
         <%# <div style="flex: 1; flex-basis: 25%; max-width: 25%;"></div> %>
-        <div style="flex: 4; flex-basis: 75%;">
+        <div style="width: 75%;">
           <%= yield %>
         </div>
       </div>