doc: fix 404 display on mobile devices
Fix display of 404 errors on mobile phones.  Also added some additional
wording for reporting errors.  (Last change, I hope :)
.. _page-not-found:
-Sorry, Page Not Found
-#####################
+Page Not Found
+##############
+
+.. rst-class:: rst-columns
.. image:: images/ACRN-fall-from-tree-small.png
:align: left
- :scale: 100%
-
-|
-| Sorry, the page you requested was not found on this site.
-|
-|
-| Please check the address for misspellings.
-| It's also possible we've removed or renamed the page you're looking for.
-|
-| Please try using the navigation links on the left of this page to navigate
-| the major sections of our site, or use the document search box.
+
+ Sorry. The page you requested was not found on this site.
+
+ Check the address for misspellings.
+ It's also possible we've removed or renamed the page you're looking for.
+
+ Try using the navigation links on the left of this page to navigate
+ the major sections of our site, or use the document search box.
+
+ If you got this error by following a link, please let us know by sending
+ us a message to `info@projectacrn.org
+ <mailto:info@projectacrn.org?subject=projectacrn.github.io%20broken%20link>`_.
.. raw:: html
