jquery.js

$('.menu-ui a').on('click', function() {
    // For each filter link, get the 'data-filter' attribute value.
    var filter = $(this).data('filter');
    $(this).addClass('active').siblings().removeClass('active');
    markers.setFilter(function(f) {
        // If the data-filter attribute is set to "all", return
        // all (true). Otherwise, filter on markers that have
        // a value set to true based on the filter name.
        return (filter === 'all') ? true : f.properties[filter] === true;
    });
    return false;
});