gulpfile.js

var gulp = require('gulp');
var less = require('gulp-less'); 
var browserSync = require('browser-sync').create();
var reload      = browserSync.reload;
 var util = require('gulp-util');
 
/* Task to compile less */
gulp.task('compile-less', function() {
// console.log("comling less");  
  gulp.src('./less/custom.less').pipe(less().on('error', util.log)).pipe(gulp.dest('./css/'));
}); 
/* Task to watch less changes */
gulp.task('watch-less', function() { 
console.log("watching less"); 
  gulp.watch('./less/*.less' , ['compile-less']);
});
 
gulp.task('serve', function () {
 	// console.log("i am started");
    // Serve files from the root of this project
    browserSync.init({
        server: {
            baseDir: "./"
        }
    }); 
    gulp.watch("./less/*.less").on("change", reload);
    gulp.watch("*.html").on("change", reload);
});
 
/* Task when running `gulp` from terminal */
gulp.task('default', ['watch-less', 'serve']);