#5F706A

CSS

:root {
  --dark-forest: #5f706a;
  --dark-forest-rgb: 95 112 106;
  --dark-forest-oklch: oklch(0.529 0.022 172.1);
}

.element {
  color: var(--dark-forest);
  background-color: hsl(159 8% 41%);
  border-color: oklch(0.529 0.022 172.1);
}

Tailwind CSS v4

@theme {
  --color-dark-forest: #5f706a;
  --color-dark-forest-50: #eff7f4;
  --color-dark-forest-100: #e1eae7;
  --color-dark-forest-200: #cbd7d3;
  --color-dark-forest-300: #acbbb6;
  --color-dark-forest-400: #92a39d;
  --color-dark-forest-500: #788b84;
  --color-dark-forest-600: #667670;
  --color-dark-forest-700: #515e5a;
  --color-dark-forest-800: #3b4541;
  --color-dark-forest-900: #28302d;
  --color-dark-forest-950: #161c1a;
}

SCSS

$dark-forest: #5f706a;
$dark-forest-rgb: 95, 112, 106;
$dark-forest-light: mix(#fff, $dark-forest, 20%);
$dark-forest-dark: mix(#000, $dark-forest, 20%);

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