#3A3E4E

CSS

:root {
  --lava-stone: #3a3e4e;
  --lava-stone-rgb: 58 62 78;
  --lava-stone-oklch: oklch(0.367 0.028 274);
}

.element {
  color: var(--lava-stone);
  background-color: hsl(228 15% 27%);
  border-color: oklch(0.367 0.028 274);
}

Tailwind CSS v4

@theme {
  --color-lava-stone: #3a3e4e;
  --color-lava-stone-50: #f3f5fd;
  --color-lava-stone-100: #e5e7f2;
  --color-lava-stone-200: #d1d3e1;
  --color-lava-stone-300: #b3b6c6;
  --color-lava-stone-400: #999eb0;
  --color-lava-stone-500: #808599;
  --color-lava-stone-600: #6c7182;
  --color-lava-stone-700: #575a68;
  --color-lava-stone-800: #3f424c;
  --color-lava-stone-900: #2b2e35;
  --color-lava-stone-950: #191a20;
}

SCSS

$lava-stone: #3a3e4e;
$lava-stone-rgb: 58, 62, 78;
$lava-stone-light: mix(#fff, $lava-stone, 20%);
$lava-stone-dark: mix(#000, $lava-stone, 20%);

.element {
  color: $lava-stone;
  box-shadow: 0 0 0 2px rgba($lava-stone, 0.35);
}