Effervescent Blue

CSS

:root {
  --effervescent-blue: #00315a;
  --effervescent-blue-rgb: 0 49 90;
  --effervescent-blue-oklch: oklch(0.309 0.088 250.2);
}

.element {
  color: var(--effervescent-blue);
  background-color: hsl(207 100% 18%);
  border-color: oklch(0.309 0.088 250.2);
}

Tailwind CSS v4

@theme {
  --color-effervescent-blue: #00315a;
  --color-effervescent-blue-50: #e4f7ff;
  --color-effervescent-blue-100: #d3ebff;
  --color-effervescent-blue-200: #bad7fa;
  --color-effervescent-blue-300: #97bbe4;
  --color-effervescent-blue-400: #76a3d1;
  --color-effervescent-blue-500: #578abe;
  --color-effervescent-blue-600: #4a75a1;
  --color-effervescent-blue-700: #3b5e81;
  --color-effervescent-blue-800: #29455f;
  --color-effervescent-blue-900: #1b3043;
  --color-effervescent-blue-950: #0b1c2b;
}

SCSS

$effervescent-blue: #00315a;
$effervescent-blue-rgb: 0, 49, 90;
$effervescent-blue-light: mix(#fff, $effervescent-blue, 20%);
$effervescent-blue-dark: mix(#000, $effervescent-blue, 20%);

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