$(document).ready(function(){

$("#about_me,#portfolio,#contact,#imprint,#portfolio_corporate,#portfolio_photography").hide();
$("#home").addClass('check');


$('h3 a').click(
    function()
    {

        var checker = $(this).attr('href');
        var anchorer = $(this);

        if ($(checker).is(":visible"))

        {
        return false;
        }

        else {          

        $("#home,#about_me,#portfolio,#contact,#imprint,#portfolio_corporate,#portfolio_photography").hide();
        $(checker).animate({"height": "toggle", "opacity": "toggle"}, "slow");
        $("#home,#about_me,#portfolio,#contact,#imprint,#portfolio_corporate,#portfolio_photography").removeClass('check');
        $(anchorer).addClass('check');

        return false;  // 





                }
   });


});