section
  -for (var x = 0; x < 100; x++)
    span

@import url('https://fonts.googleapis.com/css?family=Oswald:400,700&display=swap');

$imgUrl: 'https://picsum.photos/1920/1080?random=1';

*, *::before, *::after {
  box-sizing: border-box;
}

body {
  position: relative;
  overflow: hidden;
  
  font-family: 'Oswald', serif;
}

section {
  display: flex;
  flex-wrap: wrap;
  align-content: flex-start;
  width: 100%;
  height: 100vh;
  background: black;
  overflow: hidden;
  > span {
    width: 10%;
    height: 10%;
    background-image: url($imgUrl);
    background-attachment: fixed;
    background-size: cover;
    background-position: center center;
  }
}


button {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  border: none;
  outline: none;
  padding: 10px 15px;
  background: white;
  font-size: 1.25rem;
  
  cursor: pointer;
}

const tween = gsap.from('section > span', {
  delay: 2,
  duration: 0.1,
  x: 300,
  y: 300,
  opacity: 0,
  stagger: 0.1,
});