How to make admin panel backend FULL Width

General General Questions
1

my admin panel is smaller than my screen
need to make it wider or full width

any help appreciated!

2

At first it is required to add an ability to specify your CSS for admin panel

Then try to use the following code

#main_column {
    .navbar-admin-top, .admin-content-wrap, .content-wrap {
        max-width: none !important;
    }
}

(!) Not tested