<section class="section section--one">
  <div class="section__bg"></div>
  <div class="section__content">
    <div class="section__text">1 Lorem ipsum dolor sit amet consectetur adipisicing elit. Necessitatibus voluptates at quas architecto quidem laborum repudiandae quis eveniet. Officiis nihil ipsum incidunt soluta molestias, inventore distinctio itaque perferendis qui saepe!</div>
    <div class="section__text--copy" aria-hidden="true">1 Lorem ipsum dolor sit amet consectetur adipisicing elit. Necessitatibus voluptates at quas architecto quidem laborum repudiandae quis eveniet. Officiis nihil ipsum incidunt soluta molestias, inventore distinctio itaque perferendis qui saepe!</div>
  </div>
</section>
<section class="section section--two">
  <div class="section__bg"></div>
  <div class="section__content">
    <div class="section__text">2 Lorem ipsum dolor sit amet consectetur adipisicing elit. Necessitatibus voluptates at quas architecto quidem laborum repudiandae quis eveniet. Officiis nihil ipsum incidunt soluta molestias, inventore distinctio itaque perferendis qui saepe!</div>
    <div class="section__text--copy" aria-hidden="true">2 Lorem ipsum dolor sit amet consectetur adipisicing elit. Necessitatibus voluptates at quas architecto quidem laborum repudiandae quis eveniet. Officiis nihil ipsum incidunt soluta molestias, inventore distinctio itaque perferendis qui saepe!</div>
  </div>
</section>

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  height: 400vh;
  font-family: sans-serif;
  font-size: 1.5rem;
}

.section {
  position: relative;
  display: flex;
  align-items: center;
  text-align: center;
  padding: 15px;
  min-height: 70vh;
}

.section--two .section__bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: royalblue;
  z-index: 2;
}

.section--one .section__bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: tomato;
  z-index: 2;
}


.section__content {
  position: relative;
}

.section__text {
  position: relative;
  z-index: 1;
}

.section__text--copy {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 3;
  color: #fff;
  user-select: none;
}

gsap.registerPlugin(ScrollTrigger);

gsap
  .timeline({
    ease: "power1.in",
    scrollTrigger: {
      trigger: ".section--one",
      start: "top center",
      end: "bottom center",
      // onEnter, onLeave, onEnterBack, and onLeaveBack
      // "play", "pause", "resume", "reset", "restart", "complete", "reverse", and "none".
      toggleActions: "play reverse play reverse",
      markers: true, // debug only!
      id: 'one', // debug only!
    }
  })
  .to(".section--one .section__bg, .section--one .section__text--copy", {
    clipPath: "inset(calc(50% - 100px) round 100px)",
    duration: 0.5,
  });

gsap
  .timeline({
    ease: "power1.in",
    scrollTrigger: {
      trigger: ".section--two",
      start: "top center",
      end: "bottom center",
      toggleActions: "play reverse play reverse",
      markers: true, // debug only!
      id: 'two', // debug only!
    }
  })
  .to(".section--two .section__bg, .section--two .section__text--copy", {
    clipPath: "inset(calc(50% - 100px) round 100px)",
    duration: 0.5,
  });