#5F9FE1

CSS

:root {
  --blue-bay: #5f9fe1;
  --blue-bay-rgb: 95 159 225;
  --blue-bay-oklch: oklch(0.687 0.118 250.6);
}

.element {
  color: var(--blue-bay);
  background-color: hsl(210 68% 63%);
  border-color: oklch(0.687 0.118 250.6);
}

Tailwind CSS v4

@theme {
  --color-blue-bay: #5f9fe1;
  --color-blue-bay-50: #def8ff;
  --color-blue-bay-100: #ccebff;
  --color-blue-bay-200: #b1d8ff;
  --color-blue-bay-300: #8bbbf3;
  --color-blue-bay-400: #66a3e2;
  --color-blue-bay-500: #428ad1;
  --color-blue-bay-600: #3975b0;
  --color-blue-bay-700: #2d5d8e;
  --color-blue-bay-800: #1d4569;
  --color-blue-bay-900: #13304a;
  --color-blue-bay-950: #051c31;
}

SCSS

$blue-bay: #5f9fe1;
$blue-bay-rgb: 95, 159, 225;
$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);
}