Add browser class on html tag

javascript: add browser class on html

/*CSS Browser Selector v0.4.0 (Nov 02, 2010)
Rafael Lima (http://rafael.adm.br)
http://rafael.adm.br/css_browser_selector
License: http://creativecommons.org/licenses/by/2.5/
Contributors: http://rafael.adm.br/css_browser_selector#contributors
*/
function css_browser_selector(u) {
    var ua = u.toLowerCase(),
        is = function(t) {
            return ua.indexOf(t) > -1
        },
        g = 'gecko',
        w = 'webkit',
        s = 'safari',
        o = 'opera',
        m = 'mobile',
        h = document.documentElement,
        b = [(!(/opera|webtv/i.test(ua)) && /msie\s(\d)/.test(ua)) ? ('ie ie' + RegExp.$1) : is('firefox/2') ? g + ' ff2' : is('firefox/3.5') ? g + ' ff3 ff3_5' : is('firefox/3.6') ? g + ' ff3 ff3_6' : is('firefox/3') ? g + ' ff3' : is('gecko/') ? g : is('opera') ? o + (/version\/(\d+)/.test(ua) ? ' ' + o + RegExp.$1 : (/opera(\s|\/)(\d+)/.test(ua) ? ' ' + o + RegExp.$2 : '')) : is('konqueror') ? 'konqueror' : is('blackberry') ? m + ' blackberry' : is('android') ? m + ' android' : is('chrome') ? w + ' chrome' : is('iron') ? w + ' iron' : is('applewebkit/') ? w + ' ' + s + (/version\/(\d+)/.test(ua) ? ' ' + s + RegExp.$1 : '') : is('mozilla/') ? g : '', is('j2me') ? m + ' j2me' : is('iphone') ? m + ' iphone' : is('ipod') ? m + ' ipod' : is('ipad') ? m + ' ipad' : is('mac') ? 'mac' : is('darwin') ? 'mac' : is('webtv') ? 'webtv' : is('win') ? 'win' + (is('windows nt 6.0') ? ' vista' : '') : is('freebsd') ? 'freebsd' : (is('x11') || is('linux')) ? 'linux' : '', 'js'];
    c = b.join(' ');
    h.className += ' ' + c;
    return c;
};
css_browser_selector(navigator.userAgent);