<main>
  <section>
    <h1>
      <span>1</span>
      <span invisible class="slash">/</span>
      <span invisible>4</span>
    </h1>
    <div class="stuck">
      <h1>
        <span invisible>1</span>
        <span class="slash">/</span>
        <span>4</span> 
      </h1>
    </div> 
  </section>
  <section>
    <h1>
      <span>2</span>
      <span invisible class="slash">/</span>
      <span invisible>4</span>
    </h1>
    <div class="stuck">
      <h1>
        <span invisible>1</span>
        <span class="slash">/</span>
        <span>4</span>
      </h1>
    </div> 
  </section>
  <section>
    <h1>
      <span>3</span>
      <span invisible class="slash">/</span>
      <span invisible>4</span>
    </h1>
    <div class="stuck">
      <h1>
        <span invisible>1</span>
        <span class="slash">/</span>
        <span>4</span>
      </h1>
    </div> 
  </section>
  <section>
    <h1>
      <span>4</span>
      <span invisible class="slash">/</span>
      <span invisible>4</span>
    </h1>
    <div class="stuck">
      <h1>
        <span invisible>1</span>
        <span class="slash">/</span>
        <span>4</span>
      </h1>
    </div> 
  </section>
  <section>
    <h1>
      <span>1</span>
      <span invisible class="slash">/</span>
      <span invisible>4</span>
    </h1>
    <div class="stuck">
      <h1>
        <span invisible>1</span>
        <span class="slash">/</span>
        <span>4</span>
      </h1>
    </div> 
  </section>
</main>
main {
  max-block-size: 100vh;
  overflow-y: scroll;
  scroll-snap-type: y mandatory;
}

section {
  block-size: 100vh;
  inline-size: 100vw;
/*   scroll-snap-stop: always; */
  scroll-snap-align: start;
  display: grid;
  place-content: center;
  position: relative;
}

section:nth-of-type(odd) {
  background: black;
  color: white;
}

h1 {
  font-variant-numeric: tabular-nums;
  font-size: 25vmin;
  font-weight: 300;
  display: flex;
  align-items: center;
  gap: .5ch;
}

.slash {
  font-family: Roboto, monospace;
  font-weight: 400;
}

.stuck {
  position: absolute;
  z-index: 1;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  pointer-events: none;
  clip-path: polygon(0% 0%,100% 0%,100% 100%,0% 100%);
} 

.stuck > h1 {
  position: fixed;
  z-index: 1;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  will-change: transform;
  place-content: center;
  grid-auto-flow: column;
}

[invisible] {
  visibility: hidden;
}

body {
  margin: 0;
  box-sizing: border-box;
  font-family: system-ui, sans-serif;
}
import 'https://flackr.github.io/scroll-timeline/dist/scroll-timeline.js'

const counter = document.querySelector('main')
const slashes = document.querySelectorAll('.slash')

slashes.forEach(slash => { 
  slash.animate({
    transform: ['rotateZ(0)','rotateZ(4turn)']
  },{
    duration: 1000,
    fill: 'both',
    timeline: new ScrollTimeline({
      scrollSource: counter,
      fill: 'both',
    }),
  })
})
View Compiled

External CSS

  1. https://gitcdn.xyz/repo/octoshrimpy/blokkfont/master/blokkfont.css

External JavaScript

This Pen doesn't use any external JavaScript resources.