Light Blue Grey

CSS

:root {
  --light-blue-grey: #b7c9e2;
  --light-blue-grey-rgb: 183 201 226;
  --light-blue-grey-oklch: oklch(0.83 0.04 256.6);
}

.element {
  color: var(--light-blue-grey);
  background-color: hsl(215 43% 80%);
  border-color: oklch(0.83 0.04 256.6);
}

Tailwind CSS v4

@theme {
  --color-light-blue-grey: #b7c9e2;
  --color-light-blue-grey-50: #eef6ff;
  --color-light-blue-grey-100: #e0e9f6;
  --color-light-blue-grey-200: #cad5e6;
  --color-light-blue-grey-300: #abb8cc;
  --color-light-blue-grey-400: #8fa0b7;
  --color-light-blue-grey-500: #7588a1;
  --color-light-blue-grey-600: #637388;
  --color-light-blue-grey-700: #4f5c6d;
  --color-light-blue-grey-800: #394350;
  --color-light-blue-grey-900: #272e38;
  --color-light-blue-grey-950: #151b23;
}

SCSS

$light-blue-grey: #b7c9e2;
$light-blue-grey-rgb: 183, 201, 226;
$light-blue-grey-light: mix(#fff, $light-blue-grey, 20%);
$light-blue-grey-dark: mix(#000, $light-blue-grey, 20%);

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