#7D8D94

CSS

:root {
  --inland-waters: #7d8d94;
  --inland-waters-rgb: 125 141 148;
  --inland-waters-oklch: oklch(0.633 0.021 225.9);
}

.element {
  color: var(--inland-waters);
  background-color: hsl(198 10% 54%);
  border-color: oklch(0.633 0.021 225.9);
}

Tailwind CSS v4

@theme {
  --color-inland-waters: #7d8d94;
  --color-inland-waters-50: #eff6fa;
  --color-inland-waters-100: #e1e9ed;
  --color-inland-waters-200: #cbd6db;
  --color-inland-waters-300: #adbac0;
  --color-inland-waters-400: #92a1a8;
  --color-inland-waters-500: #788991;
  --color-inland-waters-600: #66747b;
  --color-inland-waters-700: #515d62;
  --color-inland-waters-800: #3b4448;
  --color-inland-waters-900: #282f32;
  --color-inland-waters-950: #161c1e;
}

SCSS

$inland-waters: #7d8d94;
$inland-waters-rgb: 125, 141, 148;
$inland-waters-light: mix(#fff, $inland-waters, 20%);
$inland-waters-dark: mix(#000, $inland-waters, 20%);

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