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              <figure id="video-track-container">
  <video controls id="downtown-los-angeles" autoplay >
    <source src="">
    <source src="">        <track kind="chapters" label="Locations" src="" srclang="en" default type="text/vtt" >
  <figcaption tabindex="0" role="menu" aria-label="Message Log">
    <ol id="chapters">



              * { 
  box-sizing: border-box;
  font-family: Avenir, Helvetica, sans-serif;
body { margin: 0; }
figure#video-track-container { 
  font-size: 0; 
  position: relative; 
  background: #000; 
  margin: 0; 
figure#video-track-container video { 
  width: 75%;
  height: auto;
  display: inline-block; 
figure#video-track-container figcaption { 
  position: absolute; 
  right: 0; top: 0;
  background: #222; 
  width: 25%; 
  font-size: .8rem; 
  color: #666; 
  height: 100%; 
  overflow-y: scroll; 
figure#video-track-container figcaption ol { 
  position: relative;
  list-style-type: none;
  margin: 0; 
  padding: 0; 
figure#video-track-container figcaption ol li a { 
  display: block; 
  padding: .7rem 1rem; 
  border-bottom: 1px dashed #000; 
  transition: .3s;
.current { 
  background: hsl(45,80%,50%); 
  color: #000;  
figure#video-track-container figcaption ol li a:not(.current):hover, 
figure#video-track-container figcaption ol li a:not(.current):focus { 
  background: hsl(45,80%,30%); 
  color: #000; 
  cursor: pointer;
figure#video-track-container figcaption::-webkit-scrollbar {
    width: 13px;
    height: 100%;
figure#video-track-container figcaption::-webkit-scrollbar-track {
    background-color: #000; 
figure#video-track-container figcaption::-webkit-scrollbar-thumb:vertical {
    background: hsl(45,80%,20%);
    width: 13px;
    height: 20px;

@media screen and (max-width: 500px) {
  figure#video-track-container video, 
  figure#video-track-container figcaption { 
    display: block; 
    width: 100%;
  figure#video-track-container video { 
    border-bottom: 10px solid #111;
figure#video-track-container figcaption { 
  position: static; 
  height: 200px;



              // Tracks are currently offline due to cross-origin issues

var locationList = document.getElementById("chapters"),
video = document.getElementById("downtown-los-angeles"),
trackElement = video.getElementsByTagName("track")[0];
video.addEventListener("loadedmetadata", function run_tests() {
      if (trackElement.readyState == 1) { setTimeout(run_tests, 0); } else { displayChapters(); }

function displayChapters(){
  if ((trackElement.readyState == 2) && (textTrack = trackElement.track) && (window.matchMedia("(min-width: 500px)").matches)){
        if(textTrack.kind === "chapters"){
            textTrack.mode = 'hidden';
            for (var i = 0; i < textTrack.cues.length; ++i) {
                var cue = textTrack.cues[i],
                chapterName = cue.text,
                start = cue.startTime,
                newLocale = document.createElement("li"),
                location = document.createElement("a");
                location.setAttribute('id', start);
                location.setAttribute('tabindex', '0');
                var localeDescription = document.createTextNode(cue.text);
                function() {
                	video.currentTime =;
                }, false);
		   function() {
                var currentLocation = this.activeCues[0].startTime;
                if (chapter = document.getElementById(currentLocation)) {
                	var locations = []"#chapters li a"));
                	for (var i = 0; i < locations.length; ++i) { locations[i].classList.remove("current"); } 
                  // = "-"+chapter.parentNode.offsetTop+"px";
                  // alternative approach, as scrollIntoView will cause entire page to jump if video is not at top of page