change opacity when scrolling the page

PHOTO EMBED

Mon Nov 01 2021 11:31:48 GMT+0000 (UTC)

Saved by @camtonguyen #javascript

function changeStickyOpacity() {
  	const sticky = document.querySelector('.sticky-bar');
    const range = 200;

    window.addEventListener('scroll', function () {

      const scrollTop = window.pageYOffset;
      const height = sticky.offsetHeight;
      const offset = height / 2;
      let calc = 1 - (scrollTop - offset + range) / range;
      header.style.cssText = `will-change: opacity; opacity: ${calc};`;

      if (calc > '1') {
        sticky.style.opacity = 0;
      } else if ( calc < '0' ) {
        sticky.style.opacity = 1;
      }
    });
  }
content_copyCOPY