// 監聽事件
let mousedown = false;
progress.addEventListener("click", scrub);
// progress.addEventListener("mousemove", (e) => {
//   if (mousedown) {
//     scrub(e);
//   }
// });

// if mousedown is true, moves on running scrub(), if mousedown is false, it's not going to run the scrub
progress.addEventListener("mousemove", (e) => mousedown && scrub(e));
progress.addEventListener("mousedown", () => mousedown = true);
progress.addEventListener("mouseup", () => mousedown = false);


function scrub(e) {
  // console.log(e);
  const scrubTime = (e.offsetX / progress.offsetWidth) * video.duration;
  video.currentTime = scrubTime;
}