Sharing Tailwind config with SASS (Tailwind beta & Tailwind 1.0)

main.scss

// Setting variables like this wouldn't be possible because SASS would 
// get through this file before Tailwind does (because it's PostCSS)

$--color-primary: theme('colors.blue');
$--font-serif: theme('fontFamily.serif');
  
body {
  color: rgba($--color-primary, .5);
  font-family: $font-serif;
}

// It can also be useful to customize some plugins using SASS,
// like ElementUI: https://github.com/ElemeFE/element/blob/dev/packages/theme-chalk/src/common/var.scss

$--color-white: theme('colors.white');
$--color-black: theme('colors.black');

tailwind.config.js

// https://raw.githubusercontent.com/tailwindcss/tailwindcss/master/stubs/defaultConfig.stub.js

module.exports = {
  prefix: '',
  important: false,
  separator: ':',
  theme: {
    screens: {
      sm: '640px',
      md: '768px',
      lg: '1024px',
      xl: '1280px',
    },
    colors: {
      transparent: 'transparent',

      black: '#000',
      white: '#fff',

      gray: {
        100: '#f7fafc',
        200: '#edf2f7',
        300: '#e2e8f0',
        400: '#cbd5e0',
        500: '#a0aec0',
        600: '#718096',
        700: '#4a5568',
        800: '#2d3748',
        900: '#1a202c',
      },
      red: {
        100: '#fff5f5',
        200: '#fed7d7',
        300: '#feb2b2',
        400: '#fc8181',
        500: '#f56565',
        600: '#e53e3e',
        700: '#c53030',
        800: '#9b2c2c',
        900: '#742a2a',
      },
      orange: {
        100: '#fffaf0',
        200: '#feebc8',
        300: '#fbd38d',
        400: '#f6ad55',
        500: '#ed8936',
        600: '#dd6b20',
        700: '#c05621',
        800: '#9c4221',
        900: '#7b341e',
      },
      yellow: {
        100: '#fffff0',
        200: '#fefcbf',
        300: '#faf089',
        400: '#f6e05e',
        500: '#ecc94b',
        600: '#d69e2e',
        700: '#b7791f',
        800: '#975a16',
        900: '#744210',
      },
      green: {
        100: '#f0fff4',
        200: '#c6f6d5',
        300: '#9ae6b4',
        400: '#68d391',
        500: '#48bb78',
        600: '#38a169',
        700: '#2f855a',
        800: '#276749',
        900: '#22543d',
      },
      teal: {
        100: '#e6fffa',
        200: '#b2f5ea',
        300: '#81e6d9',
        400: '#4fd1c5',
        500: '#38b2ac',
        600: '#319795',
        700: '#2c7a7b',
        800: '#285e61',
        900: '#234e52',
      },
      blue: {
        100: '#ebf8ff',
        200: '#bee3f8',
        300: '#90cdf4',
        400: '#63b3ed',
        500: '#4299e1',
        600: '#3182ce',
        700: '#2b6cb0',
        800: '#2c5282',
        900: '#2a4365',
      },
      indigo: {
        100: '#ebf4ff',
        200: '#c3dafe',
        300: '#a3bffa',
        400: '#7f9cf5',
        500: '#667eea',
        600: '#5a67d8',
        700: '#4c51bf',
        800: '#434190',
        900: '#3c366b',
      },
      purple: {
        100: '#faf5ff',
        200: '#e9d8fd',
        300: '#d6bcfa',
        400: '#b794f4',
        500: '#9f7aea',
        600: '#805ad5',
        700: '#6b46c1',
        800: '#553c9a',
        900: '#44337a',
      },
      pink: {
        100: '#fff5f7',
        200: '#fed7e2',
        300: '#fbb6ce',
        400: '#f687b3',
        500: '#ed64a6',
        600: '#d53f8c',
        700: '#b83280',
        800: '#97266d',
        900: '#702459',
      },
    },
    spacing: {
      px: '1px',
      '0': '0',
      '1': '0.25rem',
      '2': '0.5rem',
      '3': '0.75rem',
      '4': '1rem',
      '5': '1.25rem',
      '6': '1.5rem',
      '8': '2rem',
      '10': '2.5rem',
      '12': '3rem',
      '16': '4rem',
      '20': '5rem',
      '24': '6rem',
      '32': '8rem',
      '40': '10rem',
      '48': '12rem',
      '56': '14rem',
      '64': '16rem',
    },
    backgroundColor: theme => theme('colors'),
    backgroundPosition: {
      bottom: 'bottom',
      center: 'center',
      left: 'left',
      'left-bottom': 'left bottom',
      'left-top': 'left top',
      right: 'right',
      'right-bottom': 'right bottom',
      'right-top': 'right top',
      top: 'top',
    },
    backgroundSize: {
      auto: 'auto',
      cover: 'cover',
      contain: 'contain',
    },
    borderColor: theme => ({
      ...theme('colors'),
      default: theme('colors.gray.300', 'currentColor'),
    }),
    borderRadius: {
      none: '0',
      sm: '0.125rem',
      default: '0.25rem',
      lg: '0.5rem',
      full: '9999px',
    },
    borderWidth: {
      default: '1px',
      '0': '0',
      '2': '2px',
      '4': '4px',
      '8': '8px',
    },
    boxShadow: {
      default: '0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06)',
      md: '0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06)',
      lg: '0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05)',
      xl: '0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04)',
      '2xl': '0 25px 50px -12px rgba(0, 0, 0, 0.25)',
      inner: 'inset 0 2px 4px 0 rgba(0, 0, 0, 0.06)',
      outline: '0 0 0 3px rgba(66, 153, 225, 0.5)',
      none: 'none',
    },
    container: {},
    cursor: {
      auto: 'auto',
      default: 'default',
      pointer: 'pointer',
      wait: 'wait',
      text: 'text',
      move: 'move',
      'not-allowed': 'not-allowed',
    },
    fill: {
      current: 'currentColor',
    },
    flex: {
      '1': '1 1 0%',
      auto: '1 1 auto',
      initial: '0 1 auto',
      none: 'none',
    },
    flexGrow: {
      '0': '0',
      default: '1',
    },
    flexShrink: {
      '0': '0',
      default: '1',
    },
    fontFamily: {
      sans: [
        '-apple-system',
        'BlinkMacSystemFont',
        '"Segoe UI"',
        'Roboto',
        '"Helvetica Neue"',
        'Arial',
        '"Noto Sans"',
        'sans-serif',
        '"Apple Color Emoji"',
        '"Segoe UI Emoji"',
        '"Segoe UI Symbol"',
        '"Noto Color Emoji"',
      ],
      serif: [
        'Georgia',
        'Cambria',
        '"Times New Roman"',
        'Times',
        'serif',
      ],
      mono: [
        'Menlo',
        'Monaco',
        'Consolas',
        '"Liberation Mono"',
        '"Courier New"',
        'monospace',
      ],
    },
    fontSize: {
      xs: '0.75rem',
      sm: '0.875rem',
      base: '1rem',
      lg: '1.125rem',
      xl: '1.25rem',
      '2xl': '1.5rem',
      '3xl': '1.875rem',
      '4xl': '2.25rem',
      '5xl': '3rem',
      '6xl': '4rem',
    },
    fontWeight: {
      hairline: '100',
      thin: '200',
      light: '300',
      normal: '400',
      medium: '500',
      semibold: '600',
      bold: '700',
      extrabold: '800',
      black: '900',
    },
    height: theme => ({
      auto: 'auto',
      ...theme('spacing'),
      full: '100%',
      screen: '100vh',
    }),
    inset: {
      '0': '0',
      auto: 'auto',
    },
    letterSpacing: {
      tighter: '-0.05em',
      tight: '-0.025em',
      normal: '0',
      wide: '0.025em',
      wider: '0.05em',
      widest: '0.1em',
    },
    lineHeight: {
      none: '1',
      tight: '1.25',
      snug: '1.375',
      normal: '1.5',
      relaxed: '1.625',
      loose: '2',
    },
    listStyleType: {
      none: 'none',
      disc: 'disc',
      decimal: 'decimal',
    },
    margin: (theme, { negative }) => ({
      auto: 'auto',
      ...theme('spacing'),
      ...negative(theme('spacing')),
    }),
    maxHeight: {
      full: '100%',
      screen: '100vh',
    },
    maxWidth: {
      xs: '20rem',
      sm: '24rem',
      md: '28rem',
      lg: '32rem',
      xl: '36rem',
      '2xl': '42rem',
      '3xl': '48rem',
      '4xl': '56rem',
      '5xl': '64rem',
      '6xl': '72rem',
      full: '100%',
    },
    minHeight: {
      '0': '0',
      full: '100%',
      screen: '100vh',
    },
    minWidth: {
      '0': '0',
      full: '100%',
    },
    objectPosition: {
      bottom: 'bottom',
      center: 'center',
      left: 'left',
      'left-bottom': 'left bottom',
      'left-top': 'left top',
      right: 'right',
      'right-bottom': 'right bottom',
      'right-top': 'right top',
      top: 'top',
    },
    opacity: {
      '0': '0',
      '25': '0.25',
      '50': '0.5',
      '75': '0.75',
      '100': '1',
    },
    order: {
      first: '-9999',
      last: '9999',
      none: '0',
      '1': '1',
      '2': '2',
      '3': '3',
      '4': '4',
      '5': '5',
      '6': '6',
      '7': '7',
      '8': '8',
      '9': '9',
      '10': '10',
      '11': '11',
      '12': '12',
    },
    padding: theme => theme('spacing'),
    stroke: {
      current: 'currentColor',
    },
    textColor: theme => theme('colors'),
    width: theme => ({
      auto: 'auto',
      ...theme('spacing'),
      '1/2': '50%',
      '1/3': '33.33333%',
      '2/3': '66.66667%',
      '1/4': '25%',
      '2/4': '50%',
      '3/4': '75%',
      '1/5': '20%',
      '2/5': '40%',
      '3/5': '60%',
      '4/5': '80%',
      '1/6': '16.66667%',
      '2/6': '33.33333%',
      '3/6': '50%',
      '4/6': '66.66667%',
      '5/6': '83.33333%',
      '1/12': '8.33333%',
      '2/12': '16.66667%',
      '3/12': '25%',
      '4/12': '33.33333%',
      '5/12': '41.66667%',
      '6/12': '50%',
      '7/12': '58.33333%',
      '8/12': '66.66667%',
      '9/12': '75%',
      '10/12': '83.33333%',
      '11/12': '91.66667%',
      full: '100%',
      screen: '100vw',
    }),
    zIndex: {
      auto: 'auto',
      '0': '0',
      '10': '10',
      '20': '20',
      '30': '30',
      '40': '40',
      '50': '50',
    },
  },
  variants: {
    alignContent: ['responsive'],
    alignItems: ['responsive'],
    alignSelf: ['responsive'],
    appearance: ['responsive'],
    backgroundAttachment: ['responsive'],
    backgroundColor: ['responsive', 'hover', 'focus'],
    backgroundPosition: ['responsive'],
    backgroundRepeat: ['responsive'],
    backgroundSize: ['responsive'],
    borderCollapse: ['responsive'],
    borderColor: ['responsive', 'hover', 'focus'],
    borderRadius: ['responsive'],
    borderStyle: ['responsive'],
    borderWidth: ['responsive'],
    boxShadow: ['responsive', 'hover', 'focus'],
    cursor: ['responsive'],
    display: ['responsive'],
    fill: ['responsive'],
    flex: ['responsive'],
    flexDirection: ['responsive'],
    flexGrow: ['responsive'],
    flexShrink: ['responsive'],
    flexWrap: ['responsive'],
    float: ['responsive'],
    fontFamily: ['responsive'],
    fontSize: ['responsive'],
    fontSmoothing: ['responsive'],
    fontStyle: ['responsive'],
    fontWeight: ['responsive', 'hover', 'focus'],
    height: ['responsive'],
    inset: ['responsive'],
    justifyContent: ['responsive'],
    letterSpacing: ['responsive'],
    lineHeight: ['responsive'],
    listStylePosition: ['responsive'],
    listStyleType: ['responsive'],
    margin: ['responsive'],
    maxHeight: ['responsive'],
    maxWidth: ['responsive'],
    minHeight: ['responsive'],
    minWidth: ['responsive'],
    objectFit: ['responsive'],
    objectPosition: ['responsive'],
    opacity: ['responsive'],
    order: ['responsive'],
    outline: ['responsive', 'focus'],
    overflow: ['responsive'],
    padding: ['responsive'],
    pointerEvents: ['responsive'],
    position: ['responsive'],
    resize: ['responsive'],
    stroke: ['responsive'],
    tableLayout: ['responsive'],
    textAlign: ['responsive'],
    textColor: ['responsive', 'hover', 'focus'],
    textDecoration: ['responsive', 'hover', 'focus'],
    textTransform: ['responsive'],
    userSelect: ['responsive'],
    verticalAlign: ['responsive'],
    visibility: ['responsive'],
    whitespace: ['responsive'],
    width: ['responsive'],
    wordBreak: ['responsive'],
    zIndex: ['responsive'],
  },
  corePlugins: {},
  plugins: [],
}

tailwind.sass.js

const sass = require('node-sass');
const sassUtils = require('node-sass-utils')(sass);
const { theme } = require('./tailwind.config.js');

const hexToRGBA = (hex) => {
  if (!/^#([A-Fa-f0-9]{3}){1,2}$/.test(hex)) {
    return null;
  }

  let hexColor = hex.substring(1).split('');

  if (hexColor.length === 3) {
    hexColor = [hexColor[0], hexColor[0], hexColor[1], hexColor[1], hexColor[2], hexColor[2]];
  }

  return Number(`0xff${hexColor.join('')}`);
};

const convertStringToSassDimension = (result) => {
  // Only attempt to convert strings
  if (sassUtils.typeOf(result) !== 'string') {
    return result;
  }

  const cssUnits = ['rem', 'em', 'vh', 'vw', 'vmin', 'vmax', 'ex', '%', 'px', 'cm', 'mm', 'in', 'pt', 'pc', 'ch'];
  const value = result.match(/[.0-9]+/g);
  const unit = result.match(/[a-zA-Z%]+/g);

  // If the string has a unit
  if (cssUnits.indexOf(unit) !== -1) {
    return new sassUtils.SassDimension(parseInt(value, 10), unit);
  }

  // Else if the string is a hex color string, make sure we return a sass color
  //    to avoid errors when using darken, lighten, etc.
  if (/^#([A-Fa-f0-9]{3}){1,2}$/.test(result)) {
    const rgba = hexToRGBA(result);
    return sass.types.Color(rgba);
  }

  return result;
};

// sass-loader function to return specific theme item
const getConfigItem = (keys) => {
  const itemValue = keys
    ? keys.getValue().split('.').reduce((object, item) => object[item] || {}, theme)
    : theme;
  let returnValue;

  if (itemValue) {
    if (sassUtils.typeOf(itemValue) === 'string') {
      returnValue = convertStringToSassDimension(itemValue);
    } else if (sassUtils.typeOf(itemValue) === 'array') {
      returnValue = convertStringToSassDimension(itemValue.join(', '));
    } else if (sassUtils.typeOf(itemValue) === 'object') {
      returnValue = Object.keys(itemValue).reduce((object, item) => {
        let itemKeys = `${keys ? `${sassUtils.castToJs(keys)}.` : ''}${item}`;
        itemKeys = sassUtils.castToSass(itemKeys);
        return {
          ...object,
          [item]: getConfigItem(itemKeys),
        };
      }, {});
    }
  }

  return sassUtils.castToSass(returnValue);
};

// sass-loader function to return the entire theme
const getConfig = () => getConfigItem();

module.exports = {
  getConfig,
  getConfigItem,
};

vue.config.js

const tailwindSassLoader = require('./tailwind.sass')

module.exports = {
  css: {
    loaderOptions: {
      postcss: {
        plugins: (loader) => [
          tailwindcss('./tailwind.config.js'),
          autoprefixer(),
        ],
      },
      sass: {
        functions: {
          'theme($keys)': tailwindSassLoader.getConfigItem,
        },
      }
    },
  }
}

Thanks for sharing. any idea on how to use in Angular ?

Sorry, no idea!

A couple of things I want to add:

1. When using with Vite, the config is similar:

import { getConfigItem } from "./tailwind.sass"; 
// or const { getConfigItem }  = require('./tailwind.sass.js');

export default defineConfig({
    ...
    css: {
        preprocessorOptions: {
            scss: {
                functions: {
                    "theme($keys)": getConfigItem,
                },
            },
        },
    },
});

2. Later versions of node-sass (I'm on 9.0.0) have sass.types.Color deprecated and it doesn't seem to work. To fix that, replace the hexToRGBA function with this:

const hexToRGBA = (hex) => {
    const red = parseInt(hex.slice(1, 3), 16),
        green = parseInt(hex.slice(3, 5), 16),
        blue = parseInt(hex.slice(5, 7), 16);

    return {
        red,
        green,
        blue,
    };
};

https://stackoverflow.com/a/28056903/4633197

and then change the part of convertStringToSassDimension that handles the hex values to this:

if (/^#([A-Fa-f0-9]{3}){1,2}$/.test(result)) {
    const rgba = hexToRGBA(result);
    return new SassColor(rgba);
}

The SassColor constructor only takes an object of red, blue, and green, and optional alpha: https://sass-lang.com/documentation/js-api/classes/sasscolor/

Thanks for sharing 🙏