<section>
  <div class="grid__container">
    <div class="grid__item" data-item="Tom">Tom</div>
    <div class="grid__item" data-item="Jack">Jack</div>
    <div class="grid__item" data-item="Tony">Tony</div>
  </div>
  <form action="">
    <input type="range" min="0" max="100" value="100" />
  </form>
</section>

@import url("https://fonts.googleapis.com/css2?family=Exo:wght@600&display=swap");

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  width: 100vw;
  min-height: 100vh;

  display: flex;
  justify-content: center;
  flex-direction: column;
  gap: 20px;
  font-family: "Exo", Arial, sans-serif;
  background-color: #f7f7f7;

  padding: 20px;
}

section {
  min-width: 60vw;
  margin: 0 auto;

  display: flex;
  justify-content: center;
  /*   align-items: center; */
  flex-direction: column;

  gap: 10px;
  box-shadow: 0 0 0 6px rgb(0 0 0 / 13%);
  border-radius: 6px;
}

.grid__container {
  border: 1px dashed #f36;
  border-radius: 1px;
}

form {
  width: 100%;
}
input[type="range"] {
  width: 100%;
}

.grid__item {
  display: flex;
  justify-content: center;
  align-items: center;
  background-color: #f7f7f7;
  font-size: 2rem;
  color: #fff;
  text-shadow: 1px 1px 0 rgb(0 0 0 / 0.5), -1px -1px 0 rgb(0 0 0 / 0.05);
  font-weight: 500;
  caret-color: #f36;
  min-height: 20vmin;
}

.grid__item:nth-child(1) {
  background-color: #f1c2c6;
}

.grid__item:nth-child(2) {
  background-color: #dac2f1;
}

.grid__item:nth-child(3) {
  background-color: #ccf1c2;
}

.grid__container {
  --width: 100%;
  width: var(--width);
  gap: 5px;
  display: grid;
  grid-template-columns: minmax(100px, 200px) minmax(100px, 200px) minmax(
      100px,
      200px
    );
}

const range = document.querySelector('input[type="range"]');
const container = document.querySelector(".grid__container");

range.addEventListener("input", (etv) => {
  container.style.setProperty("--width", `${etv.target.value}%`);
});