Bug 36265: Bigger font-size for headers in staff interface

Bug 36265: Bigger font-size for headers in staff interface

In staff interface, text in nav bar and search header are at normal
size. Since these are used a lot, I propose to increase font-size at
110%.

Test by applying patch and rebuild CSS to see bigger text in staff
interface

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>
(cherry picked from commit 8ee1ce0cd2f9d6b513de6e9e7f421976dc2529da)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>