dev-mode.js

$(function () {
    if (location.hash == '#dev') {
        $('body').addClass('dev').attr('id', 'dev');

        $btn = $('<button/>', {
            text: 'Toggle'
        }).css({
            position: 'fixed',
            right   : 0,
            bottom  : 0,
            zIndex  : 2147483647,
            fontSize: '30px'
        });
        $btn.appendTo('body');

        var old   = true;
        var $link = $('head').find('link[href="assets/templates/101/style.css"]');
        var toggleStyles = function() {
            if (old) {
                var time = new Date();
                v        = time.getTime();
                $link.attr('href', 'assets/templates/101/style2.css' + '?v=' + v);
            } else {
                $link.attr('href', 'assets/templates/101/style.css');
            }
            old = !old;
        }
        toggleStyles();
        
        $btn.on('click', toggleStyles);

        $('a[href]').each(function () {
            var href = $(this).attr('href');
            if (href.substr(0, 1) != '#') {
                $(this).attr('href', href + '#dev');
            }
        });

    }
});