<section>
  <div class="grid__container">
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
    <div class="grid__item"></div>
  </div>
</section>

<div class="form">
  <label for="row-gap">row-gap:</label>
  <input type="range" value="10" min="0" max="50" id="row-gap" name="gap" />
  <output id="row-gap-output">10px</output>
  <label for="column-gap">column-gap:</label>
  <input type="range" value="10" min="0" max="50" id="column-gap" name="gap" />
  <output id="column-gap-output">10px</output>
</div>
@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 {
  margin: 0 auto;

  display: flex;
  box-shadow: 0 0 0 6px rgb(0 0 0 / 13%);
  border-radius: 3px;
  gap: 20px;
  min-width: 40vw;
}

.grid__item {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 5px;
  background-color: #f7f7f7;
  position: relative;
  counter-increment: item;
}

.grid__item::before {
  content: counter(item);
  color: #fff;
  font-size: 1.2rem;
  text-shadow: 1px 1px 0 rgba(0 0 0 / 0.25);
  z-index: 2;
  background-color: rgb(0 0 0 / 0.6);
  background-image: conic-gradient(
    from 90deg at 40% -25%,
    #ffd700,
    #f79d03,
    #ee6907,
    #e6390a,
    #de0d0d,
    #d61039,
    #cf1261,
    #c71585,
    #cf1261,
    #d61039,
    #de0d0d,
    #ee6907,
    #f79d03,
    #ffd700,
    #ffd700,
    #ffd700
  );
  width: 32px;
  aspect-ratio: 1 / 1;
  display: inline-flex;
  justify-content: center;
  align-items: center;
  border-radius: 50%;
}

.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__item:nth-child(4) {
  background-color: #c2e9f1;
}

.grid__item:nth-child(5) {
  background-color: #f1ebc2;
}
.grid__item:nth-child(6) {
  background-color: #09f;
}

.grid__item:nth-child(7) {
  background-color: #ff5722;
}

.grid__item:nth-child(8) {
  background-color: #8bc34a;
}

.grid__item:nth-child(9) {
  background-color: #f66803;
}

.grid__item:nth-child(10) {
  background-color: #0d815f;
}
.grid__item:nth-child(11) {
  background-color: #28d1c2;
}
.grid__item:nth-child(12) {
  background-color: #4a28d1;
}

.form {
  width: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 15px;
}

.grid__container {
  box-shadow: 0 0 0 2px red;
  border-radius: 2px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  width: 100%;

  --row-gap: 10px;
  --column-gap: 10px;
  row-gap: var(--row-gap);
  column-gap: var(--column-gap);
}
const gridContainer = document.querySelector(".grid__container");
const ranges = document.querySelectorAll("input[type='range']");

ranges.forEach((range) => {
  range.addEventListener("change", (etv) => {
    gridContainer.style.setProperty(
      `--${etv.target.id}`,
      `${etv.target.value}px`
    );
    document.getElementById(
      `${etv.target.id}-output`
    ).textContent = `${etv.target.value}px`;
  });
});
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