Smooth page scrolling using JavaScript

You can find many examples of solving this problem, for example, on jQuery. But in some cases, when other effects are not needed on the site, connecting a whole library is stupid. It makes much more sense to use pure JavaScript.

document.body.addEventListener('click', function (e) {
    if (e.target.tagName === 'A' && e.target.getAttribute('href').startsWith('#')) {
       e.preventDefault();
 
       const blockID = e.target.getAttribute('href').slice(1);
       const targetBlock = document.getElementById(blockID);
 
       if (targetBlock) {
          targetBlock.scrollIntoView({
             behavior: 'smooth',
             block: 'start'
          });
       }
    }
});