CSS
Block Scroll
In css we define
html,body {overflow:hidden;} to prevent the user to scroll outside of our Three.js canvas.
Fixed position for element
With fixed the element stays in the viewport
Full screen sections
.section {
  display: flex;
  align-items: center;
  height: 100vh;
  position: relative;
  padding-left: 10%;
  padding-right: 10%;
}