Fixes few regressions caused by my last PR.
Fixes few regressions caused by my last PR.

It tranaformed our css to the "mobile-first" paradigm so @media
query now targets large screens.
This commit also fixes share icon in the left sidebar.

Signed-off-by: Marin Treselj <52d9a2cc899a8db7044d09f9abec336fb5fb7086@pixelipo.com>

juliushaertl/deck,nextcloud/deck,juliushaertl/deck,juliushaertl/deck,nextcloud/deck,SpaceCafe/deck,nextcloud/deck,SpaceCafe/deck,SpaceCafe/deck