#3FA4DB

CSS

:root {
  --high-blue: #3fa4db;
  --high-blue-rgb: 63 164 219;
  --high-blue-oklch: oklch(0.684 0.123 236.6);
}

.element {
  color: var(--high-blue);
  background-color: hsl(201 68% 55%);
  border-color: oklch(0.684 0.123 236.6);
}

Tailwind CSS v4

@theme {
  --color-high-blue: #3fa4db;
  --color-high-blue-50: #d6fbff;
  --color-high-blue-100: #c3efff;
  --color-high-blue-200: #a3dcff;
  --color-high-blue-300: #79c0ef;
  --color-high-blue-400: #4ca9dd;
  --color-high-blue-500: #0090cc;
  --color-high-blue-600: #0c7aac;
  --color-high-blue-700: #0b628a;
  --color-high-blue-800: #014866;
  --color-high-blue-900: #023248;
  --color-high-blue-950: #001e2f;
}

SCSS

$high-blue: #3fa4db;
$high-blue-rgb: 63, 164, 219;
$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);
}