html:not(.disable_user_stylesheet) * { background-color: #ffffff !important; }
html:not(.disable_user_stylesheet) * { color: black !important; }
html:not(.disable_user_stylesheet) :link { color: blue !important; text-decoration: none; }
html:not(.disable_user_stylesheet) :visited { color: #800080 !important; text-decoration: none; }