function player(element,iframe){
  var track = element.querySelector("track");
  track.addEventListener('cuechange', function () {
    let cues = track.track.activeCues;  // array of current cues
    console.log("cuechange", cues, cues[0].text, cues[0].startTime, cues[0].endTime);
    var d = JSON.parse(cues[0].text);
    console.log("d",d);
    var old = element.querySelector(".now_playing");
      if (old) {
        old.classList.remove("now_playing");
      }
    var playing = document.getElementById(d.title);
    playing.classList.add("now_playing");
    console.log("playing",playing);

    if (iframe&&d.artist) {
      iframe.src = d.artist;
    }
  
  });
}