#1A5FF5

CSS

:root {
  --blue-ribbon: #1a5ff5;
  --blue-ribbon-rgb: 26 95 245;
  --blue-ribbon-oklch: oklch(0.545 0.234 262.8);
}

.element {
  color: var(--blue-ribbon);
  background-color: hsl(221 92% 53%);
  border-color: oklch(0.545 0.234 262.8);
}

Tailwind CSS v4

@theme {
  --color-blue-ribbon: #1a5ff5;
  --color-blue-ribbon-50: #d4f5ff;
  --color-blue-ribbon-100: #c1e7ff;
  --color-blue-ribbon-200: #a2d1ff;
  --color-blue-ribbon-300: #7bb1ff;
  --color-blue-ribbon-400: #4f95ff;
  --color-blue-ribbon-500: #2674ff;
  --color-blue-ribbon-600: #2263f0;
  --color-blue-ribbon-700: #1b4fc1;
  --color-blue-ribbon-800: #063b91;
  --color-blue-ribbon-900: #052867;
  --color-blue-ribbon-950: #001547;
}

SCSS

$blue-ribbon: #1a5ff5;
$blue-ribbon-rgb: 26, 95, 245;
$blue-ribbon-light: mix(#fff, $blue-ribbon, 20%);
$blue-ribbon-dark: mix(#000, $blue-ribbon, 20%);

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