Detect browser with JS

    /** OS **/
    var OSName="unknown";
    if (navigator.appVersion.indexOf("Win")!=-1) OSName="win";
    if (navigator.appVersion.indexOf("Mac")!=-1) OSName="mac";
    if (navigator.appVersion.indexOf("X11")!=-1) OSName="unix";
    if (navigator.appVersion.indexOf("Linux")!=-1) OSName="linux";
    $('html').addClass('os-'+OSName);


    /** Browser **/
    /*eslint-disable*/
    // Opera 8.0+
    var isOpera = (!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;
    if( isOpera ) {
      $('html').addClass('browser-opera');
    }
    // Firefox 1.0+
    var isFirefox = typeof InstallTrigger !== 'undefined';
    if( isFirefox ) {
      $('html').addClass('browser-firefox');
    }
    // Safari 3.0+ "[object HTMLElementConstructor]" 
    var isSafari = /constructor/i.test(window.HTMLElement) || (function (p) { return p.toString() === "[object SafariRemoteNotification]"; })(!window['safari'] || (typeof safari !== 'undefined' && safari.pushNotification));
    if( isSafari ) {
      $('html').addClass('browser-safari');
    }
    // Internet Explorer 6-11
    var isIE = /*@cc_on!@*/false || !!document.documentMode;
    if( isIE ) {
      $('html').addClass('browser-ie');
    }
    // Edge 20+
    var isEdge = !isIE && !!window.StyleMedia;
    if( isEdge ) {
      $('html').addClass('browser-edge');
    }
    // Chrome 1+
    var isChrome = !!window.chrome && !!window.chrome.webstore;
    if( isChrome ) {
      $('html').addClass('browser-chrome');
    }
    // Blink engine detection
    var isBlink = (isChrome || isOpera) && !!window.CSS;
    if( isBlink ) {
      $('html').addClass('browser-blink');
    }

    // iOS version
    var iOS = parseFloat(
	('' + (/CPU.*OS ([0-9_]{1,5})|(CPU like).*AppleWebKit.*Mobile/i.exec(navigator.userAgent) || [0,''])[1])
	.replace('undefined', '3_2').replace('_', '.').replace('_', '')
    ) || false;
    if( iOS ) {
      if( iOS < 10.3 ) {
        $('html').addClass('ios-'+iOS+' grid-not-supported');
      }
      if (iOS < 10 ) {
        $('.section-intro-bg video, .section-intro-bg .video-js').remove();
      }
    }
    /*eslint-disable*/