const playerButton = document.querySelector('.player-button'), audio = document.querySelector('audio'), playIcon = ` `, pauseIcon = ` `; function toggleAudio() { if (audio.paused) { audio.play(); playerButton.innerHTML = pauseIcon; } else { audio.pause(); playerButton.innerHTML = playIcon; } } playerButton.addEventListener('click', toggleAudio); function audioEnded() { playerButton.innerHTML = playIcon; } audio.onended = audioEnded; const timeline = document.querySelector('.timeline'); function changeTimelinePosition() { const percentagePosition = (100 * audio.currentTime) / audio.duration; timeline.style.backgroundSize = `${percentagePosition}% 100%`; timeline.value = percentagePosition; } audio.ontimeupdate = changeTimelinePosition; function changeSeek() { const time = (timeline.value * audio.duration) / 100; audio.currentTime = time; } timeline.addEventListener('change', changeSeek);