Twilight Blue

CSS

:root {
  --twilight-blue: #0a437a;
  --twilight-blue-rgb: 10 67 122;
  --twilight-blue-oklch: oklch(0.381 0.108 252.8);
}

.element {
  color: var(--twilight-blue);
  background-color: hsl(209 85% 26%);
  border-color: oklch(0.381 0.108 252.8);
}

Tailwind CSS v4

@theme {
  --color-twilight-blue: #0a437a;
  --color-twilight-blue-50: #e1f7ff;
  --color-twilight-blue-100: #d0eaff;
  --color-twilight-blue-200: #b5d7ff;
  --color-twilight-blue-300: #92baee;
  --color-twilight-blue-400: #6fa2dd;
  --color-twilight-blue-500: #4e89cc;
  --color-twilight-blue-600: #4374ac;
  --color-twilight-blue-700: #355d8a;
  --color-twilight-blue-800: #234466;
  --color-twilight-blue-900: #172f48;
  --color-twilight-blue-950: #081c2f;
}

SCSS

$twilight-blue: #0a437a;
$twilight-blue-rgb: 10, 67, 122;
$twilight-blue-light: mix(#fff, $twilight-blue, 20%);
$twilight-blue-dark: mix(#000, $twilight-blue, 20%);

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