Code Playground

@charset "UTF-8";
@import url(https://fonts.googleapis.com/css?family=Nunito+Sans:300,400,600,700,800);
*,
:after,
:before {
  box-sizing: border-box;
  padding: 0;
  margin: 0;
}
:root {
  --sizeVar: 2vw;
  --animVar: 200ms;
}

body {
  background-color: #ffffff;
  position: absolute;
  inset: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow: hidden;
}

.flex {
  position: absolute;
  display: flex;
  background-color: #ffffff;
  padding: calc(var(--sizeVar) * 2.5);
  border-radius: calc(var(--sizeVar) * 1.5);
  box-shadow: 0 var(--sizeVar) calc(var(--sizeVar) * 0.5) #00000033,
    0 0 calc(var(--sizeVar) * 0.5) calc(var(--sizeVar) * 0.2) #00000006;
  justify-content: center;
  align-items: center;
  gap: var(--sizeVar);
}
.key {
  width: calc(var(--sizeVar) * 5.6);
  aspect-ratio: 1 / 1;
  background-color: #ffffff;
  display: flex;
  justify-content: center;
  align-items: center;
  border-radius: calc(var(--sizeVar) * 0.7);
  font-size: calc(var(--sizeVar) * 2);
  font-family: sans-serif;
  font-weight: 300;
  color: #dddddd;
  cursor: pointer;
  box-shadow: 0 var(--sizeVar) calc(var(--sizeVar) * 0.5) #00000055,
    0 0 calc(var(--sizeVar) * 0.5) calc(var(--sizeVar) * 0.2) #00000011;
  transition: filter var(--animVar) ease-in-out 0s,
    box-shadow var(--animVar) ease-in-out 0s,
    color var(--animVar) ease-in-out 0s;
}

.key:hover {
  filter: brightness(97%);
  box-shadow: 0 calc(var(--sizeVar) * 0.5) calc(var(--sizeVar) * 0.5) #00000055,
    0 0 calc(var(--sizeVar) * 0.5) calc(var(--sizeVar) * 0.2) #00000011;
}

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