#6E9FD1

CSS

:root {
  --blue-bay: #6e9fd1;
  --blue-bay-rgb: 110 159 209;
  --blue-bay-oklch: oklch(0.687 0.091 249.8);
}

.element {
  color: var(--blue-bay);
  background-color: hsl(210 52% 63%);
  border-color: oklch(0.687 0.091 249.8);
}

Tailwind CSS v4

@theme {
  --color-blue-bay: #6e9fd1;
  --color-blue-bay-50: #e3f8ff;
  --color-blue-bay-100: #d3ebff;
  --color-blue-bay-200: #b9d8fb;
  --color-blue-bay-300: #96bbe5;
  --color-blue-bay-400: #74a3d2;
  --color-blue-bay-500: #558ac0;
  --color-blue-bay-600: #4875a2;
  --color-blue-bay-700: #395e82;
  --color-blue-bay-800: #274560;
  --color-blue-bay-900: #1a3044;
  --color-blue-bay-950: #0b1c2c;
}

SCSS

$blue-bay: #6e9fd1;
$blue-bay-rgb: 110, 159, 209;
$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);
}