<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">
  <lable>
    align-content:
    <select name="align-content" id="align-content">
      <option value="normal">normal</option>
      <option value="start">start</option>
      <option value="end">end</option>
      <option value="center">center</option>
      <option value="stretch">stretch</option>
      <option value="space-around">space-around</option>
      <option value="space-between">space-between</option>
      <option value="space-evenly">space-evenly</option>
      <option value="baseline">baseline</option>
      <option value="first baseline">first baseline</option>
      <option value="last baseline">last baseline</option>
    </select>
  </lable>
</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;
}

.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(3, 100px);
  grid-template-rows: repeat(3, 100px);
  height: 500px;
  width: 500px;
  grid-gap: 10px;

  --align-content: start;
  align-content: var(--align-content);
}

const gridContainer = document.querySelector(".grid__container");
const selectElement = document.getElementById("align-content");

selectElement.addEventListener("change", (etv) => {
  gridContainer.style.setProperty("--align-content", etv.target.value);
});