#2E3A45

CSS

:root {
  --tempest-in-a-teapot: #2e3a45;
  --tempest-in-a-teapot-rgb: 46 58 69;
  --tempest-in-a-teapot-oklch: oklch(0.342 0.025 246.3);
}

.element {
  color: var(--tempest-in-a-teapot);
  background-color: hsl(209 20% 23%);
  border-color: oklch(0.342 0.025 246.3);
}

Tailwind CSS v4

@theme {
  --color-tempest-in-a-teapot: #2e3a45;
  --color-tempest-in-a-teapot-50: #f0f6fc;
  --color-tempest-in-a-teapot-100: #e2e9f0;
  --color-tempest-in-a-teapot-200: #ccd5df;
  --color-tempest-in-a-teapot-300: #aeb9c4;
  --color-tempest-in-a-teapot-400: #93a0ad;
  --color-tempest-in-a-teapot-500: #798896;
  --color-tempest-in-a-teapot-600: #67737f;
  --color-tempest-in-a-teapot-700: #525c66;
  --color-tempest-in-a-teapot-800: #3b444b;
  --color-tempest-in-a-teapot-900: #292f34;
  --color-tempest-in-a-teapot-950: #171b1f;
}

SCSS

$tempest-in-a-teapot: #2e3a45;
$tempest-in-a-teapot-rgb: 46, 58, 69;
$tempest-in-a-teapot-light: mix(#fff, $tempest-in-a-teapot, 20%);
$tempest-in-a-teapot-dark: mix(#000, $tempest-in-a-teapot, 20%);

.element {
  color: $tempest-in-a-teapot;
  box-shadow: 0 0 0 2px rgba($tempest-in-a-teapot, 0.35);
}