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HTML 

              
                <div class="u-textCenter">
  <h1 class="Title">The<br> Night<br> Sky*</h1>
</div>
!

CSS 

              
                @import url('https://fonts.googleapis.com/css?family=Kanit:800');

$c-orange: #f7933c;
$c-yellow: #fbd773;
$c-white: #ffffff;
$c-blue: #303846;

.sky {
  position: absolute;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;

  &.is-sticky {
    position: fixed;
    backface-visibility: hidden;
  }

  &.is-bottom {
    top: auto;
    bottom: 0;
  }
}

.star {
  position: absolute;
  width: 0.75em;
  height: 0.25em;
  margin-bottom: 0.25em;
  margin-top: 0.25em;
  background-color: $c-orange;
  opacity: 0.5;
  animation: twinkle1 3s infinite ease-in-out;

  &::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    width: 0.25em;
    height: 1em * (2 / 3);
    margin: auto;
    background-color: $c-yellow;
  }
}

.star--1 {
  animation-name: twinkle2;
  animation-duration: 4s;
}

.star--2 {
  animation-name: twinkle3;
  animation-duration: 5s;
}

@keyframes twinkle1 {
  100%,
  20% {
    opacity: 0.333;
  }

  0% {
    opacity: 0.333;
  }

  10% {
    opacity: 0.6;
  }
}

@keyframes twinkle2 {
  100%,
  30% {
    opacity: 0.25;
  }

  0% {
    opacity: 0.25;
  }

  10% {
    opacity: 0.6;
  }
}

@keyframes twinkle3 {
  100%,
  25% {
    opacity: 0.25;
  }

  0% {
    opacity: 0.25;
  }

  10% {
    opacity: 0.6;
  }
}

body {
  display: flex;
  justify-content: center;
  align-items: center;
  align-content: center;
  min-height: 100vh;
  color: $c-white;
  background-color: $c-blue;
}

.Title {
  @include responsive-font(10vw, 50px, 126px, 50px);
  font-family: 'Kanit', Helvetica, Arial, sans-serif;
  font-weight: 800;
  line-height: 0.7;
  text-transform: uppercase;
  position: relative;
  margin: 0.2em;
}

.u-textCenter {
  text-align: center;
}
!

JS 

              
                const $body = document.querySelector("body");
let $sky, count, delay = 0;
let canvas = {
  width: window.innerWidth,
  height: window.innerHeight
};

initSky();
// window.addEventListener('resize', resetSky);

// Random number generator within range
function rng(min, max) {
  return Math.round(Math.random() * (max - min) + min);
}

// Get number of stars based on screen height with a base count of 5
function getStarCount() {
  return Math.round(canvas.height / 100) + 5;
}

function createSky() {
  // Create sky element
  const $newSky = document.createElement("div");
  $newSky.classList.add("sky");
  count = getStarCount();

  // Add star elements to sky
  for (let i = 0; i < count; i++) {
    const $star = createStar();
    $newSky.appendChild($star);
  }

  return $newSky;
}

function createStar() {
  const $star = document.createElement("div");
  const y = rng(0, 100);
  const x = rng(-5, 20);

  // Add base star class and modifier to adjust twinkle timing
  $star.classList.add("star", "star--" + rng(1, 3));

  // Randomly position star to the left or right of the screen
  if (rng(0, 1) === 1) {
    $star.setAttribute(
      "style",
      "top: " + y + "%; left: " + x + "%; animation-delay: " + delay + "ms;"
    );
  } else {
    $star.setAttribute(
      "style",
      "top: " + y + "%; right: " + x + "%; animation-delay: " + delay + "ms;"
    );
  }

  delay += 175;

  return $star;
}

function initSky() {
  $sky = createSky();
  $body.appendChild($sky);

  // Make sky position fixed when infographic hits the top of the screen
  // let waypointTop = new Waypoint({
  //     element: $body[0],
  //     handler: function(direction) {
  //         if (direction === 'down') {
  //             $sky.classList.add('is-sticky');
  //         } else if (direction === 'up') {
  //             $sky.classList.remove('is-sticky');
  //         }
  //     },
  //     offset: 0
  // });

  // Make sky position absolute when infographic hits the bottom of the screen
  // let waypointBottom = new Waypoint({
  //     element: $body[0],
  //     handler: function(direction) {
  //         if (direction === 'down') {
  //             $sky.classList.remove('is-sticky');
  //             $sky.classList.add('is-bottom');
  //         } else if (direction === 'up') {
  //             $sky.classList.add('is-sticky');
  //             $sky.classList.remove('is-bottom');
  //         }
  //     },
  //     offset: 'bottom-in-view'
  // });
}

// function resetSky() {
//     canvas.width = window.innerWidth;
//     canvas.height = window.innerHeight;
//     const $container = $sky.parentElement;
//     const $newSky = createSky();
//
//     if ($container) {
//         $container.replaceChild($newSky, $sky);
//         $sky = $newSky;
//     }
// }
!
999px

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