sass main src sass main scss dest public main css landing src sass lan

        sass: {
            main: {
                src: 'sass/main.scss',
                dest: 'public/main.css'
            },
            landing: {
                src: 'sass/landing.scss',
                dest: 'public/landing.css'
            }
        },

...

grunt.loadNpmTasks('grunt-contrib-sass');
grunt.registerTask('build', ['mkdir', 'symlink', 'sass', 'ngtemplates', 'concat']);