var vid = document.getElementById('dices__video'); 

document.getElementById('btn_1').addEventListener('click', () => {
  vid.currentTime = 0;
  vid.play();
});
document.getElementById('btn_2').addEventListener('click', () => {
  vid.currentTime = 10;
  vid.play();
});
document.getElementById('btn_3').addEventListener('click', () => {
  vid.currentTime = 20;
  vid.play();
});