#1A866A

CSS

:root {
  --shadows-of-time: #1a866a;
  --shadows-of-time-rgb: 26 134 106;
  --shadows-of-time-oklch: oklch(0.555 0.103 170.2);
}

.element {
  color: var(--shadows-of-time);
  background-color: hsl(164 68% 31%);
  border-color: oklch(0.555 0.103 170.2);
}

Tailwind CSS v4

@theme {
  --color-shadows-of-time: #1a866a;
  --color-shadows-of-time-50: #d9fff2;
  --color-shadows-of-time-100: #c6f4e4;
  --color-shadows-of-time-200: #a7e3cf;
  --color-shadows-of-time-300: #7ec9b2;
  --color-shadows-of-time-400: #58b295;
  --color-shadows-of-time-500: #249c7c;
  --color-shadows-of-time-600: #228469;
  --color-shadows-of-time-700: #1c6954;
  --color-shadows-of-time-800: #144e3c;
  --color-shadows-of-time-900: #0d3629;
  --color-shadows-of-time-950: #012117;
}

SCSS

$shadows-of-time: #1a866a;
$shadows-of-time-rgb: 26, 134, 106;
$shadows-of-time-light: mix(#fff, $shadows-of-time, 20%);
$shadows-of-time-dark: mix(#000, $shadows-of-time, 20%);

.element {
  color: $shadows-of-time;
  box-shadow: 0 0 0 2px rgba($shadows-of-time, 0.35);
}