<%# having width=100% on the table and then only a fixed width on the middle cell gives us a max-width that works in Outlook %>
<%# the "width: 100%" here looks wrong, but I couldn't find a better way of making Outlook give this cell full width %>
<%= image_tag attachments["logo.png"].url, alt: "OpenStreetMap", title: "OpenStreetMap", height: "30", width: "30", border: "0" %> <%# NB we need "text-decoration: none" twice: GMail only honours it on the but Outlook only on the %> OpenStreetMap
<%= raw style_message(yield) %>
<%= yield :footer %>