<div>Primary</div>
<pre class="language-css">
<code>
:root {
  --primary-hue: 250;
  --primary-saturation: 100%;
  --primary-lightness: 90%;
  
  --primary-light: hsl(
    var(--primary-hue) var(--primary-saturation) var(--primary-lightness)
  );
  --on-primary-light: hsl(var(--primary-hue) var(--primary-saturation) 10%);
  
  --surface1-light: hsl(var(--primary-hue) 40% 90%);
  --surface2-light: hsl(var(--primary-hue) 30% 99%);
  --surface3-light: hsl(var(--primary-hue) 30% 92%);
  --surface4-light: hsl(var(--primary-hue) 30% 85%);
  
  --primary-light: hsl(
    var(--primary-hue) var(--primary-saturation) var(--primary-lightness)
  );
  --surface-shadow-light: var(--primary-hue) 40% 10%;
  --shadow-strength-light: 0.02;
}

div {
  background-color: var(--primary-light);
  color: var(--on-primary-light);
  box-shadow: 0 2.8px 2.2px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.03)
      ),
    0 6.7px 5.3px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.01)
      ),
    0 12.5px 10px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.02)
      ),
    0 22.3px 17.9px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.02)
      ),
    0 41.8px 33.4px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.03)
      ),
    0 100px 80px hsl(var(--surface-shadow-light) / var(--shadow-strength-light));
}
</code>
</pre>

@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: #f9f9f9;
  padding: 20px;

  display: grid;
  gap: 10px;
  place-content: center;
}

:root {
  --primary-hue: 250;
  --primary-saturation: 100%;
  --primary-lightness: 90%;
  --primary-light: hsl(
    var(--primary-hue) var(--primary-saturation) var(--primary-lightness)
  );
  --on-primary-light: hsl(var(--primary-hue) var(--primary-saturation) 10%);

  --surface1-light: hsl(var(--primary-hue) 40% 90%);
  --surface2-light: hsl(var(--primary-hue) 30% 99%);
  --surface3-light: hsl(var(--primary-hue) 30% 92%);
  --surface4-light: hsl(var(--primary-hue) 30% 85%);

  --surface-shadow-light: var(--primary-hue) 40% 10%;
  --shadow-strength-light: 0.02;
}

div {
  width: 30vmin;
  margin: 0 auto;
  display: flex;
  justify-content: center;
  align-items: center;
  aspect-ratio: 1 / 1;
  border-radius: 10px;
  background-color: var(--primary-light);
  color: var(--on-primary-light);
  box-shadow: 0 2.8px 2.2px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.03)
      ),
    0 6.7px 5.3px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.01)
      ),
    0 12.5px 10px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.02)
      ),
    0 22.3px 17.9px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.02)
      ),
    0 41.8px 33.4px
      hsl(
        var(--surface-shadow-light) / calc(var(--shadow-strength-light) + 0.03)
      ),
    0 100px 80px hsl(var(--surface-shadow-light) / var(--shadow-strength-light));
}