javascript - How to detect margin-left of element with jQuery -

wird, thought obvious not necessarily, can tell me how detect margin jquery? have , in console have result it's not working on page:

var margin_left = circle.css('margin-left').tolowercase(); circles_container.css('margin-left', -margin_left + 'px'); 

much thx help.

i should more accurate:

var margin_left = circle.css('margin-left'); circles_container.css({marginleft: '-'+margin_left});