because it is at the and of a line and has a space in the middle between the two words.
add something like this to style.css of your theme:
.mbtn{display:inline-block;}
or for a different effect, try:
.mbtn{display:block;}
http://codex.wordpress.org/Editing_Files
to edit the style.css of your theme:
goto to ‘dashboard’ ‘appearance’ ‘editor’ and select style.css from the list on the right (if it is not already selected)
then scroll down in the editor window, and add the suggested css code at the end; click ‘update file’.
then click top left on the name of your site to get you back to the front; press ‘reload’ on your browser to refresh the browser cache, and see if the changes have solved you r problem.
