#2C70AA

CSS

:root {
  --muted-blue: #2c70aa;
  --muted-blue-rgb: 44 112 170;
  --muted-blue-oklch: oklch(0.53 0.114 247.8);
}

.element {
  color: var(--muted-blue);
  background-color: hsl(208 59% 42%);
  border-color: oklch(0.53 0.114 247.8);
}

Tailwind CSS v4

@theme {
  --color-muted-blue: #2c70aa;
  --color-muted-blue-50: #ddf9ff;
  --color-muted-blue-100: #ccecff;
  --color-muted-blue-200: #b0d9ff;
  --color-muted-blue-300: #8abcf0;
  --color-muted-blue-400: #65a4de;
  --color-muted-blue-500: #3f8bcd;
  --color-muted-blue-600: #3776ad;
  --color-muted-blue-700: #2c5e8b;
  --color-muted-blue-800: #1c4667;
  --color-muted-blue-900: #123048;
  --color-muted-blue-950: #041c2f;
}

SCSS

$muted-blue: #2c70aa;
$muted-blue-rgb: 44, 112, 170;
$muted-blue-light: mix(#fff, $muted-blue, 20%);
$muted-blue-dark: mix(#000, $muted-blue, 20%);

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