<% unless logged_in? %>
  	<%= link_to image_tag('sustain.png', width: 336, height: 280), 'https://sustainoss.org/?utm_source=libraries.io&utm_medium=280x336-ad' %>
<% end %>

<% unless logged_in? %>
  	<%= link_to image_tag('sustain.png', style: 'max-width:100%;'), 'https://sustainoss.org/?utm_source=libraries.io&utm_medium=280x336-ad' %>
<% end %>

Use max width on sustain advert to avoid breaking on small screens
Use max width on sustain advert to avoid breaking on small screens
