#00467D

CSS

:root {
  --mermaid-blues: #00467d;
  --mermaid-blues-rgb: 0 70 125;
  --mermaid-blues-oklch: oklch(0.389 0.111 250.3);
}

.element {
  color: var(--mermaid-blues);
  background-color: hsl(206 100% 25%);
  border-color: oklch(0.389 0.111 250.3);
}

Tailwind CSS v4

@theme {
  --color-mermaid-blues: #00467d;
  --color-mermaid-blues-50: #dff8ff;
  --color-mermaid-blues-100: #ceebff;
  --color-mermaid-blues-200: #b3d8ff;
  --color-mermaid-blues-300: #8ebbef;
  --color-mermaid-blues-400: #6aa3de;
  --color-mermaid-blues-500: #478acd;
  --color-mermaid-blues-600: #3d75ad;
  --color-mermaid-blues-700: #315e8b;
  --color-mermaid-blues-800: #204567;
  --color-mermaid-blues-900: #153048;
  --color-mermaid-blues-950: #061c2f;
}

SCSS

$mermaid-blues: #00467d;
$mermaid-blues-rgb: 0, 70, 125;
$mermaid-blues-light: mix(#fff, $mermaid-blues, 20%);
$mermaid-blues-dark: mix(#000, $mermaid-blues, 20%);

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