#4E7B9F

CSS

:root {
  --zenith: #4e7b9f;
  --zenith-rgb: 78 123 159;
  --zenith-oklch: oklch(0.565 0.075 243.8);
}

.element {
  color: var(--zenith);
  background-color: hsl(207 34% 46%);
  border-color: oklch(0.565 0.075 243.8);
}

Tailwind CSS v4

@theme {
  --color-zenith: #4e7b9f;
  --color-zenith-50: #e4f8ff;
  --color-zenith-100: #d4ebff;
  --color-zenith-200: #bbd8f3;
  --color-zenith-300: #98bcdc;
  --color-zenith-400: #78a4c8;
  --color-zenith-500: #598cb4;
  --color-zenith-600: #4c7698;
  --color-zenith-700: #3c5f7a;
  --color-zenith-800: #2a465a;
  --color-zenith-900: #1c303f;
  --color-zenith-950: #0c1c28;
}

SCSS

$zenith: #4e7b9f;
$zenith-rgb: 78, 123, 159;
$zenith-light: mix(#fff, $zenith, 20%);
$zenith-dark: mix(#000, $zenith, 20%);

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