Как сделать плавную прокрутку сайта кнопкой пробел?

    

  // Get the height of the viewport 

const viewportHeight = window.innerHeight; 

// Set the scroll speed 

const scrollSpeed = 20; 

// Listen for the spacebar keydown event 

document.addEventListener('keydown', function(event) { 

  if (event.code === 'Space') { 

    // Prevent the default behavior of the spacebar 

    event.preventDefault(); 

    // Calculate the distance to scroll 

    const distanceToScroll = viewportHeight - window.pageYOffset; 

    // Calculate the duration of the scroll animation 

    const duration = distanceToScroll / scrollSpeed; 

    // Animate the scroll 

    animateScroll(distanceToScroll, duration); 

  } 

}); 

// Animate the scroll 

function animateScroll(distanceToScroll, duration) { 

  let start = window.pageYOffset; 

  let currentTime = 0; 

  // Use requestAnimationFrame to animate the scroll 

  function animate() { 

    currentTime += 1 / 60; 

    const ease = Math.sin(currentTime / duration * (Math.PI / 2)); 

    const newPosition = start + distanceToScroll * ease; 

    window.scrollTo(0, newPosition); 

    if (currentTime < duration) { 

      requestAnimationFrame(animate); 

    } 

  } 

  animate(); 

}