fix layouting of middle blocks in IE

app/views/my_projects_overviews/index.html.erb

@@ -39,12 +39,10 @@ See doc/COPYRIGHT.md for more details.
 <% end %>
 
 <div id="invisible-grid">
-  <div class="grid-block medium-up-1">
   <% top_fields.each do |f| %>
     <%= rendered_field f %>
   <% end %>
-  </div>
+  <div class="grid-block">
-  <div class="grid-block medium-up-2">
     <% middle_fields.each do |f| %>
       <%= rendered_field f %>
     <% end %>

app/views/my_projects_overviews/page_layout.html.erb

@@ -42,11 +42,10 @@ See doc/COPYRIGHT.md for more details.
 
 <h4><%=l(:label_visible_elements) %></h4>
 <div id="visible-grid">
-  <div class="grid-block medium-up-1">
   <% top_fields.each do |f| %>
     <%= grid_field f %>
   <% end %>
-  </div>
+
   <div class="grid-block">
     <% middle_fields.each do |f| %>
       <%= grid_field f %>