#464678

CSS

:root {
  --tangent-periwinkle: #464678;
  --tangent-periwinkle-rgb: 70 70 120;
  --tangent-periwinkle-oklch: oklch(0.418 0.082 282.2);
}

.element {
  color: var(--tangent-periwinkle);
  background-color: hsl(240 26% 37%);
  border-color: oklch(0.418 0.082 282.2);
}

Tailwind CSS v4

@theme {
  --color-tangent-periwinkle: #464678;
  --color-tangent-periwinkle-50: #f2f3ff;
  --color-tangent-periwinkle-100: #e4e5ff;
  --color-tangent-periwinkle-200: #cfd0f7;
  --color-tangent-periwinkle-300: #b2b2e1;
  --color-tangent-periwinkle-400: #9699ce;
  --color-tangent-periwinkle-500: #7e7fbb;
  --color-tangent-periwinkle-600: #6a6c9e;
  --color-tangent-periwinkle-700: #55567f;
  --color-tangent-periwinkle-800: #3d3f5e;
  --color-tangent-periwinkle-900: #2a2b42;
  --color-tangent-periwinkle-950: #17192b;
}

SCSS

$tangent-periwinkle: #464678;
$tangent-periwinkle-rgb: 70, 70, 120;
$tangent-periwinkle-light: mix(#fff, $tangent-periwinkle, 20%);
$tangent-periwinkle-dark: mix(#000, $tangent-periwinkle, 20%);

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