#3A7E9E

CSS

:root {
  --cry-me-a-river: #3a7e9e;
  --cry-me-a-river-rgb: 58 126 158;
  --cry-me-a-river-oklch: oklch(0.563 0.084 231.3);
}

.element {
  color: var(--cry-me-a-river);
  background-color: hsl(199 46% 42%);
  border-color: oklch(0.563 0.084 231.3);
}

Tailwind CSS v4

@theme {
  --color-cry-me-a-river: #3a7e9e;
  --color-cry-me-a-river-50: #dffaff;
  --color-cry-me-a-river-100: #cdedff;
  --color-cry-me-a-river-200: #b1dbf3;
  --color-cry-me-a-river-300: #8cbfdc;
  --color-cry-me-a-river-400: #68a8c8;
  --color-cry-me-a-river-500: #4390b4;
  --color-cry-me-a-river-600: #3a7a98;
  --color-cry-me-a-river-700: #2e627a;
  --color-cry-me-a-river-800: #1f485a;
  --color-cry-me-a-river-900: #14323f;
  --color-cry-me-a-river-950: #061e28;
}

SCSS

$cry-me-a-river: #3a7e9e;
$cry-me-a-river-rgb: 58, 126, 158;
$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);
}