gruntfile.js

module.exports = function(grunt) {

  // Project configuration.
  grunt.initConfig({
    pkg: grunt.file.readJSON('package.json'),

    watch: {
      scripts: {
        files: ['src/stylesheets/**/*.scss', 'src/stylesheets/theme.scss'],
        tasks: ['sass']
      }
    },

    sass: {                              // Task
      dist: {                            // Target
        options: {                       // Target options
          style: 'expanded',
          sourcemap: 'none'
        },
        files: {                         // Dictionary of files
          'assets/theme.css': 'src/stylesheets/theme.scss'       // 'destination': 'source'
        }
      }
    }
  });

  // Load the plugin that provides the "uglify" task.
  grunt.loadNpmTasks('grunt-contrib-watch');
  grunt.loadNpmTasks('grunt-contrib-sass');
  // Default task(s).
  grunt.registerTask('default', ['watch']);
};