#2370E4

CSS

:root {
  --deep-sky-blue: #2370e4;
  --deep-sky-blue-rgb: 35 112 228;
  --deep-sky-blue-oklch: oklch(0.566 0.191 259.2);
}

.element {
  color: var(--deep-sky-blue);
  background-color: hsl(216 78% 52%);
  border-color: oklch(0.566 0.191 259.2);
}

Tailwind CSS v4

@theme {
  --color-deep-sky-blue: #2370e4;
  --color-deep-sky-blue-50: #d7f7ff;
  --color-deep-sky-blue-100: #c4e9ff;
  --color-deep-sky-blue-200: #a6d5ff;
  --color-deep-sky-blue-300: #7eb6ff;
  --color-deep-sky-blue-400: #549cff;
  --color-deep-sky-blue-500: #287fff;
  --color-deep-sky-blue-600: #246cd9;
  --color-deep-sky-blue-700: #1d56af;
  --color-deep-sky-blue-800: #0b4083;
  --color-deep-sky-blue-900: #072c5c;
  --color-deep-sky-blue-950: #00183f;
}

SCSS

$deep-sky-blue: #2370e4;
$deep-sky-blue-rgb: 35, 112, 228;
$deep-sky-blue-light: mix(#fff, $deep-sky-blue, 20%);
$deep-sky-blue-dark: mix(#000, $deep-sky-blue, 20%);

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