Switch to side-by-side view

--- a/website/release-1.18.html
+++ b/website/release-1.18.html
@@ -66,7 +66,7 @@
         you have not chosen to just delete the whole index
         directory.</p>
 
-      <p><em>Viewer exceptions</em>: 
+      <p><span class="important">Viewer exceptions</span>: 
         There is a new list of mime types that should be opened with
         the locally configured application even when <em>Use
           Desktop Preferences</em> is checked. This allows making