#1C6EBA

CSS

:root {
  --matt-blue: #1c6eba;
  --matt-blue-rgb: 28 110 186;
  --matt-blue-oklch: oklch(0.531 0.141 251.3);
}

.element {
  color: var(--matt-blue);
  background-color: hsl(209 74% 42%);
  border-color: oklch(0.531 0.141 251.3);
}

Tailwind CSS v4

@theme {
  --color-matt-blue: #1c6eba;
  --color-matt-blue-50: #daf8ff;
  --color-matt-blue-100: #c7ebff;
  --color-matt-blue-200: #aad8ff;
  --color-matt-blue-300: #83bbfe;
  --color-matt-blue-400: #5aa3ef;
  --color-matt-blue-500: #2f89df;
  --color-matt-blue-600: #2a74bc;
  --color-matt-blue-700: #225d97;
  --color-matt-blue-800: #124571;
  --color-matt-blue-900: #0c2f4f;
  --color-matt-blue-950: #011b35;
}

SCSS

$matt-blue: #1c6eba;
$matt-blue-rgb: 28, 110, 186;
$matt-blue-light: mix(#fff, $matt-blue, 20%);
$matt-blue-dark: mix(#000, $matt-blue, 20%);

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