<section>
  <div class="grid__container">
    <div class="grid__item">
      <img src="https://picsum.photos/400/300?random=1" alt="">
    </div>
    <div class="grid__item">
      <img src="https://picsum.photos/400/300?random=2" alt="">
    </div>
    <div class="grid__item">
      <img src="https://picsum.photos/400/300?random=3" alt="">
    </div>
    <div class="grid__item">
      <img src="https://picsum.photos/400/300?random=4" alt="">
    </div>
    <div class="grid__item">
      <img src="https://picsum.photos/400/300?random=5" alt="">
    </div>
  </div>
</section>

<form action="">
  <span>grid-auto-flow:</span>
  <label for="row">
    <input type="radio" name="grid-auto-flow" id="row" checked value="row" />
    row(Initial)
  </label>
  <label for="column">
    <input type="radio" name="grid-auto-flow" id="column" value="column" />
    column
  </label>
  <label for="dense">
    <input type="radio" name="grid-auto-flow" id="dense" value="dense" />
    dense
  </label>
  <label for="row-dense">
    <input type="radio" name="grid-auto-flow" id="row-dense" value="row dense" />
    row dense
  </label>
  <label for="column-dense">
    <input type="radio" name="grid-auto-flow" id="column-dense" value="column dense" />
    column dense
  </label>
</form>

@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;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  box-shadow: 0 0 0 6px rgb(0 0 0 / 13%);
  border-radius: 3px;
  gap: 20px;
}

img {
  aspect-ratio: 16 / 9;
  max-width: 100%;
  filter: drop-shadow(1px 1px 2px rgb(255 255 255 / 0.5))
    drop-shadow(-1px -1px 2px rgb(255 255 255 / 0.5));
  mix-blend-mode: luminosity;
  border-radius: 4px;
}

.grid__container {
  box-shadow: 0 0 0 1px #f36;
  position: relative;
}

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

.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;
}
h3 {
  margin: 20px auto;
}

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

label {
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

.grid__container {
  display: grid;
  grid-template-columns: repeat(2, 100px);
  --grid-auto-flow: row;
  grid-auto-flow: var(--grid-auto-flow);
  gap: 10px;
}

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

radios.forEach((radio, index) => {
  radio.addEventListener("click", (etv) => {
    container.style.setProperty("--grid-auto-flow", etv.target.value);
  });
});