<div class="box box__slower">Normal Box Shadow Transition (Slower)</div>
<div class="box box__faster">Pseudo-Element Opacity Transition (Faster)</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;
  font-family: "Exo", Arial, sans-serif;
  background-color: rgb(237 242 247);
  padding: 20px;

  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 200px), 1fr));
  gap: 60px;
}

.box {
  aspect-ratio: 16 / 9;
  background-color: #fff;
  border-radius: 10px;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: clamp(20px, 3vw + 2rem, 30px);
}

.box__slower {
  box-shadow: 0 3px 3px rgba(0, 0, 0, 0.2);
}

.box__slower:hover {
  box-shadow: 0 3px 3px rgba(0, 0, 0, 0.7);
  transition: box-shadow 500ms;
}

.box__faster {
  position: relative;
  box-shadow: 0 0 10px 0 rgba(0, 0, 0, 0.2);
}

.box__faster::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 10px;
  box-shadow: 0 1px 1px rgba(0, 0, 0, 0.12), 0 2px 2px rgba(0, 0, 0, 0.12),
    0 4px 4px rgba(0, 0, 0, 0.12), 0 8px 8px rgba(0, 0, 0, 0.12),
    0 16px 16px rgba(0, 0, 0, 0.12);
  opacity: 0;
  transition: opacity 500ms;
}
.box__faster:hover::after {
  opacity: 1;
}