#C4D1E3

CSS

:root {
  --misty-mountains: #c4d1e3;
  --misty-mountains-rgb: 196 209 227;
  --misty-mountains-oklch: oklch(0.856 0.029 256.5);
}

.element {
  color: var(--misty-mountains);
  background-color: hsl(215 36% 83%);
  border-color: oklch(0.856 0.029 256.5);
}

Tailwind CSS v4

@theme {
  --color-misty-mountains: #c4d1e3;
  --color-misty-mountains-50: #f0f6fe;
  --color-misty-mountains-100: #e2e8f2;
  --color-misty-mountains-200: #cdd5e1;
  --color-misty-mountains-300: #afb8c6;
  --color-misty-mountains-400: #949fb0;
  --color-misty-mountains-500: #7a879a;
  --color-misty-mountains-600: #677382;
  --color-misty-mountains-700: #535c68;
  --color-misty-mountains-800: #3c434c;
  --color-misty-mountains-900: #292e35;
  --color-misty-mountains-950: #171b20;
}

SCSS

$misty-mountains: #c4d1e3;
$misty-mountains-rgb: 196, 209, 227;
$misty-mountains-light: mix(#fff, $misty-mountains, 20%);
$misty-mountains-dark: mix(#000, $misty-mountains, 20%);

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