Added Font Awesome and used it in some headers.
Added separate menu to header/panel

Menu appears in header or panel depending on screen width.
Redesigned header

Adapt coloring and popup login form for narrow screens.
Enhanced CSS for panel

Made it fixed, provided sufficient width. Also, don't show embeddings on
narrow screens.
Redesigned buttons

Added symbols, minified for narrow screens and moved to the inner side on
task.php.
Enhanced user table; marking head, body and foot
Small corrections