$(function () {

$('a[href="#search"]').on('click', function(event) {
    event.preventDefault();
    $('#search').addClass('open');
    $('#search > form > input[type="search"]').focus();
});

$('#search, #search button.close').on('click keyup', function(event) {
    if (event.target == this || event.target.className == 'close' || event.keyCode == 27) {
        $(this).removeClass('open');
    }
});

});