#426D3B

CSS

:root {
  --under-the-radar: #426d3b;
  --under-the-radar-rgb: 66 109 59;
  --under-the-radar-oklch: oklch(0.49 0.091 141);
}

.element {
  color: var(--under-the-radar);
  background-color: hsl(112 30% 33%);
  border-color: oklch(0.49 0.091 141);
}

Tailwind CSS v4

@theme {
  --color-under-the-radar: #426d3b;
  --color-under-the-radar-50: #e7fce5;
  --color-under-the-radar-100: #d7f0d5;
  --color-under-the-radar-200: #bedfbc;
  --color-under-the-radar-300: #9dc49a;
  --color-under-the-radar-400: #81ac7a;
  --color-under-the-radar-500: #64955c;
  --color-under-the-radar-600: #557e4e;
  --color-under-the-radar-700: #44653e;
  --color-under-the-radar-800: #324a2b;
  --color-under-the-radar-900: #22331d;
  --color-under-the-radar-950: #111f0d;
}

SCSS

$under-the-radar: #426d3b;
$under-the-radar-rgb: 66, 109, 59;
$under-the-radar-light: mix(#fff, $under-the-radar, 20%);
$under-the-radar-dark: mix(#000, $under-the-radar, 20%);

.element {
  color: $under-the-radar;
  box-shadow: 0 0 0 2px rgba($under-the-radar, 0.35);
}