#4E4CD3

CSS

:root {
  --warm-blue: #4e4cd3;
  --warm-blue-rgb: 78 76 211;
  --warm-blue-oklch: oklch(0.503 0.201 277);
}

.element {
  color: var(--warm-blue);
  background-color: hsl(241 61% 56%);
  border-color: oklch(0.503 0.201 277);
}

Tailwind CSS v4

@theme {
  --color-warm-blue: #4e4cd3;
  --color-warm-blue-50: #e8f0ff;
  --color-warm-blue-100: #d9e2ff;
  --color-warm-blue-200: #c2cbff;
  --color-warm-blue-300: #a2aaff;
  --color-warm-blue-400: #838dff;
  --color-warm-blue-500: #6b6eff;
  --color-warm-blue-600: #5a5dde;
  --color-warm-blue-700: #484bb2;
  --color-warm-blue-800: #313786;
  --color-warm-blue-900: #21265f;
  --color-warm-blue-950: #111341;
}

SCSS

$warm-blue: #4e4cd3;
$warm-blue-rgb: 78, 76, 211;
$warm-blue-light: mix(#fff, $warm-blue, 20%);
$warm-blue-dark: mix(#000, $warm-blue, 20%);

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