<section>
  <div class="container">
    <div class="box auto"> 16 / 9</div>
    <div class="box fixed__height">16 / 9</div>
    <div class="box fixed__width">16 / 9</div>
    <div class="box fixed__height__width">16 / 9</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 {
  width: 100%;
  margin: 0 auto;
  max-width: 40vw;
  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;
}

.container {
  box-shadow: 0 0 0 1px #f36;
  position: relative;
  gap: 20px;
}

.box {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 10px;
  background-color: #f7f7f7;
  box-shadow: 0 0 0 1px #09f;
  white-space: nowrap;
}

.box:not(:last-child) {
  margin-bottom: 20px;
}

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

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

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

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

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

.container {
  --width: 100%;
  width: var(--width);
}

.box {
  aspect-ratio: 16/9;
}

.fixed__height {
  height: 100px;
}

.fixed__width {
  width: 200px;
}

.fixed__height__width {
  width: 200px;
  height: 100px;
}

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

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