Iron River

CSS

:root {
  --iron-river: #4d504b;
  --iron-river-rgb: 77 80 75;
  --iron-river-oklch: oklch(0.427 0.009 132.5);
}

.element {
  color: var(--iron-river);
  background-color: hsl(96 3% 30%);
  border-color: oklch(0.427 0.009 132.5);
}

Tailwind CSS v4

@theme {
  --color-iron-river: #4d504b;
  --color-iron-river-50: #f4f6f3;
  --color-iron-river-100: #e6e8e5;
  --color-iron-river-200: #d3d5d1;
  --color-iron-river-300: #b5b8b4;
  --color-iron-river-400: #9ca09a;
  --color-iron-river-500: #848781;
  --color-iron-river-600: #70736e;
  --color-iron-river-700: #595c58;
  --color-iron-river-800: #414340;
  --color-iron-river-900: #2d2e2c;
  --color-iron-river-950: #1a1b19;
}

SCSS

$iron-river: #4d504b;
$iron-river-rgb: 77, 80, 75;
$iron-river-light: mix(#fff, $iron-river, 20%);
$iron-river-dark: mix(#000, $iron-river, 20%);

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