https://blockstream.com/assets/js/new-landing.js

1const scrollElements = document.querySelectorAll(".scrollElement");
2
3
4const options = {
5  root: null,
6  rootMargin: '0px',
7  threshold: 0.1
8}
9
10const observer = new IntersectionObserver((entries) => {
11
12    entries.forEach(entry => {
13        if(entry.isIntersecting) {
14            entry.target.classList.add("slideUp");
15        }  
16    })
17}, options);
18
19scrollElements.forEach(animatedElement => {
20    observer.observe(animatedElement)
21});
22
23document.addEventListener('DOMContentLoaded', function() {
24    const oval1 = document.getElementById('parallax-oval-1');
25    const oval2 = document.getElementById('parallax-oval-2');
26    
27    function updateParallax() {
28      const scrollPosition = window.scrollY;
29      
30      const oval1Offset = scrollPosition * 0.5; 
31      const oval2Offset = -scrollPosition * 0.5; 
32      
33      oval1.style.transform = `translateY(${oval1Offset}px)`;
34      oval2.style.transform = `translateY(${oval2Offset}px)`;
35      
36    }
37    
38    let ticking = false;
39    
40    function onScroll() {
41      if (!ticking) {
42        window.requestAnimationFrame(function() {
43          updateParallax();
44          ticking = false;
45        });
46        ticking = true;
47      }
48    }
49    
50    window.addEventListener('scroll', onScroll, { passive: true });
51    
52    updateParallax();
53  });