#649DE4

CSS

:root {
  --blue-bay: #649de4;
  --blue-bay-rgb: 100 157 228;
  --blue-bay-oklch: oklch(0.687 0.121 254.6);
}

.element {
  color: var(--blue-bay);
  background-color: hsl(213 70% 64%);
  border-color: oklch(0.687 0.121 254.6);
}

Tailwind CSS v4

@theme {
  --color-blue-bay: #649de4;
  --color-blue-bay-50: #dff7ff;
  --color-blue-bay-100: #ceeaff;
  --color-blue-bay-200: #b3d7ff;
  --color-blue-bay-300: #8fbaf5;
  --color-blue-bay-400: #6ba1e5;
  --color-blue-bay-500: #4988d5;
  --color-blue-bay-600: #3f73b3;
  --color-blue-bay-700: #325c90;
  --color-blue-bay-800: #20446b;
  --color-blue-bay-900: #152f4b;
  --color-blue-bay-950: #071b32;
}

SCSS

$blue-bay: #649de4;
$blue-bay-rgb: 100, 157, 228;
$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);
}