jQuery toggle CSS?

I want to toggle between CSS so when a user clicks the button (#user_button) it shows the menu (#user_options) and changes the CSS, and when the user clicks it again it goes back to normal. So far this is all I have:

$('#user_button').click( function() {
    $('#user_options').toggle();
    $("#user_button").css({    
        borderBottomLeftRadius: '0px',
        borderBottomRightRadius: '0px'
    }); 
    return false;
});

Can anybody help?