#3FA2E3

CSS

:root {
  --high-blue: #3fa2e3;
  --high-blue-rgb: 63 162 227;
  --high-blue-oklch: oklch(0.683 0.132 241.5);
}

.element {
  color: var(--high-blue);
  background-color: hsl(204 75% 57%);
  border-color: oklch(0.683 0.132 241.5);
}

Tailwind CSS v4

@theme {
  --color-high-blue: #3fa2e3;
  --color-high-blue-50: #d6faff;
  --color-high-blue-100: #c3eeff;
  --color-high-blue-200: #a3dbff;
  --color-high-blue-300: #79bff6;
  --color-high-blue-400: #4ca7e5;
  --color-high-blue-500: #028ed5;
  --color-high-blue-600: #0d79b4;
  --color-high-blue-700: #0d6190;
  --color-high-blue-800: #01476b;
  --color-high-blue-900: #02314b;
  --color-high-blue-950: #001d32;
}

SCSS

$high-blue: #3fa2e3;
$high-blue-rgb: 63, 162, 227;
$high-blue-light: mix(#fff, $high-blue, 20%);
$high-blue-dark: mix(#000, $high-blue, 20%);

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