Drop down menu current page

I have drop down menu and so far i made something like this
[URL=”http://jsbin.com/amofoz/11/edit”]http://jsbin.com/amofoz/11/edit[/URL]
I want to make my menu expand on a current page. Now it is but “+” is replaced with “-” when it is expanded (it should be “-“) Also when both (“Pierwsze” and “Drugie”) are expanded and when i close on “Pierwsze” then also “drugie” is closing. But when i have both closed and i click “Drugie” to expand then “Pierwsze” is also expanding. By the way i want when “pierwsze” ius expanded and then i click on “Drugie” then “Pierwsze” should be closed. Sorry for my english. I hope i described it properly. I don’t know how to do that drop down menu to work good.

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