#6B9ED6

CSS

:root {
  --blue-bay: #6b9ed6;
  --blue-bay-rgb: 107 158 214;
  --blue-bay-oklch: oklch(0.686 0.1 251.6);
}

.element {
  color: var(--blue-bay);
  background-color: hsl(211 57% 63%);
  border-color: oklch(0.686 0.1 251.6);
}

Tailwind CSS v4

@theme {
  --color-blue-bay: #6b9ed6;
  --color-blue-bay-50: #e2f7ff;
  --color-blue-bay-100: #d1ebff;
  --color-blue-bay-200: #b7d7ff;
  --color-blue-bay-300: #94bbea;
  --color-blue-bay-400: #72a2d8;
  --color-blue-bay-500: #528ac6;
  --color-blue-bay-600: #4675a7;
  --color-blue-bay-700: #375d86;
  --color-blue-bay-800: #264563;
  --color-blue-bay-900: #192f46;
  --color-blue-bay-950: #0a1c2d;
}

SCSS

$blue-bay: #6b9ed6;
$blue-bay-rgb: 107, 158, 214;
$blue-bay-light: mix(#fff, $blue-bay, 20%);
$blue-bay-dark: mix(#000, $blue-bay, 20%);

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