#666C80

CSS

:root {
  --ashen-whisper: #666c80;
  --ashen-whisper-rgb: 102 108 128;
  --ashen-whisper-oklch: oklch(0.533 0.032 272.1);
}

.element {
  color: var(--ashen-whisper);
  background-color: hsl(226 11% 45%);
  border-color: oklch(0.533 0.032 272.1);
}

Tailwind CSS v4

@theme {
  --color-ashen-whisper: #666c80;
  --color-ashen-whisper-50: #f2f5ff;
  --color-ashen-whisper-100: #e4e7f3;
  --color-ashen-whisper-200: #d0d4e2;
  --color-ashen-whisper-300: #b2b7c8;
  --color-ashen-whisper-400: #979eb2;
  --color-ashen-whisper-500: #7e859c;
  --color-ashen-whisper-600: #6b7184;
  --color-ashen-whisper-700: #565a6a;
  --color-ashen-whisper-800: #3e424e;
  --color-ashen-whisper-900: #2b2e36;
  --color-ashen-whisper-950: #181a21;
}

SCSS

$ashen-whisper: #666c80;
$ashen-whisper-rgb: 102, 108, 128;
$ashen-whisper-light: mix(#fff, $ashen-whisper, 20%);
$ashen-whisper-dark: mix(#000, $ashen-whisper, 20%);

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