#3D7B9B

CSS

:root {
  --cry-me-a-river: #3d7b9b;
  --cry-me-a-river-rgb: 61 123 155;
  --cry-me-a-river-oklch: oklch(0.555 0.081 233.3);
}

.element {
  color: var(--cry-me-a-river);
  background-color: hsl(200 44% 42%);
  border-color: oklch(0.555 0.081 233.3);
}

Tailwind CSS v4

@theme {
  --color-cry-me-a-river: #3d7b9b;
  --color-cry-me-a-river-50: #e0faff;
  --color-cry-me-a-river-100: #cfedff;
  --color-cry-me-a-river-200: #b4dbf2;
  --color-cry-me-a-river-300: #8fbfdb;
  --color-cry-me-a-river-400: #6ca7c7;
  --color-cry-me-a-river-500: #498fb3;
  --color-cry-me-a-river-600: #3f7997;
  --color-cry-me-a-river-700: #326179;
  --color-cry-me-a-river-800: #224759;
  --color-cry-me-a-river-900: #17313f;
  --color-cry-me-a-river-950: #071d28;
}

SCSS

$cry-me-a-river: #3d7b9b;
$cry-me-a-river-rgb: 61, 123, 155;
$cry-me-a-river-light: mix(#fff, $cry-me-a-river, 20%);
$cry-me-a-river-dark: mix(#000, $cry-me-a-river, 20%);

.element {
  color: $cry-me-a-river;
  box-shadow: 0 0 0 2px rgba($cry-me-a-river, 0.35);
}