old_contents: var autoprefixer = require('autoprefixer');
  var cssimport = require('postcss-import');
  var data = require('gulp-data');
  var gulp = require('gulp');
  var nunjucks = require('gulp-nunjucks-render');
  var postcss = require('gulp-postcss');
  var prettify = require('gulp-prettify');
  
  const SRC = '.';
  const DEST = './build';
  
  // environment function for nunjucks
  var env = function(environment) {
  	environment.addGlobal('lang', 'ur');
  	environment.addGlobal('char_categories', {
          "alphabets": "آ ا أ ب پ ت ٹ ث ج چ ح خ د ڈ ذ ر ڑ ز ژ س ش ص ض ط ظ ع غ ف ق ک گ ل م ن ں و ؤ ہ ۂ ۃ ھ ء ئ ی ے",
  		"digits": "۰ ۱ ۲ ۳ ۴ ۵ ۶ ۷ ۸ ۹ 0 1 2 3 4 5 6 7 8 9",
  		"diacritics": "َ ِ ُ ٰ ٖ ً ٗ ْ ّ ٔ ٘",
  		"punctuation": "۔ ؟ ! ، : ؛ ' \" - ( ) [ ] { } / \\ ؏ ؎ ؁ ؍ ؃ ؀ ؂ ٫",
  		"honorifics": "ﷻ ؐ ﷺ ؑ ؓ ؒ ؔ",
  		"misc": "﷽ ZWNJ ZWJ RLM LRM ` ~ + = _ | @ # $ ٪ ^ & * < >"
      });
  	
  	environment.addFilter('split', function(str) {
  		return str.split(' ');
  	});
  	
  }
  
  gulp.task('pages', function () {
  	return gulp.src([
  			SRC + '/pages/**/*.njk',
  			'!' + SRC + '/pages/helpers/*.njk'
  		])
  		.pipe(data(function() {
  			return require(SRC + '/data.json')
  		}))
  		.pipe(nunjucks({
  			manageEnv: env,
  			path: SRC + '/pages/'
  		}))
  		.pipe(prettify({indent_size: 2}))
  		.pipe(gulp.dest(DEST));
  });
  
  gulp.task('fonts', function() {
  	return gulp.src(SRC + '/assets/type/**/*')
  		.pipe(gulp.dest(DEST + '/assets/type'));
  });
  
  // Screen CSS
  gulp.task('css', function() {
  	var processors = [
  		cssimport(),
  		autoprefixer({
  			browsers: ['last 2 versions']
  		})
      ];
  	
      return gulp.src(SRC + '/assets/css/style*.css')
  		.pipe(postcss(processors))
  		.pipe(gulp.dest(DEST + '/assets/css'));
  });
  
  // Print CSS
  //gulp.task('cssp', function() {
  //	return gulp.src(SRC + '/assets/css/print*.css')
  //		.pipe(gulp.dest(DEST + '/assets/css'));
  //});
  //
  //gulp.task('css', ['csss', 'cssp']);
  
  gulp.task('default', ['css', 'fonts', 'pages']);
  
new_contents: var autoprefixer = require('autoprefixer');
  var cssimport = require('postcss-import');
  var data = require('gulp-data');
  var gulp = require('gulp');
  var nunjucks = require('gulp-nunjucks-render');
  var postcss = require('gulp-postcss');
  var prettify = require('gulp-prettify');
  
  const SRC = '.';
  const DEST = './build';
  
  // environment function for nunjucks
  var env = function(environment) {
  	environment.addGlobal('lang', 'ur');
  	environment.addGlobal('char_categories', {
          "alphabets": "آ ا أ ب پ ت ٹ ث ج چ ح خ د ڈ ذ ر ڑ ز ژ س ش ص ض ط ظ ع غ ف ق ک گ ل م ن ں و ؤ ہ ۂ ۃ ھ ء ئ ی ے",
  		"digits": "۰ ۱ ۲ ۳ ۴ ۵ ۶ ۷ ۸ ۹ 0 1 2 3 4 5 6 7 8 9",
  		"diacritics": "َ ِ ُ ٰ ٖ ً ٗ ْ ّ ٔ ٘",
  		"punctuation": "۔ ؟ ! ، : ؛ ' \" - ( ) [ ] { } / \\ ؏ ؎ ؁ ؍ ؃ ؀ ؂ ٫",
  		"honorifics": "ﷻ ؐ ﷺ ؑ ؓ ؒ ؔ",
  		"misc": "﷽ ZWNJ ZWJ RLM LRM ` ~ + = _ | @ # $ ٪ ^ & * < >"
      });
  	
  	environment.addFilter('split', function(str) {
  		return str.split(' ');
  	});
  	
  }
  
  gulp.task('pages', function () {
  	return gulp.src([
  			SRC + '/pages/**/*.njk',
  			'!' + SRC + '/pages/helpers/*.njk'
  		])
  		.pipe(data(function() {
  			return require(SRC + '/data.json')
  		}))
  		.pipe(nunjucks({
  			manageEnv: env,
  			path: SRC + '/pages/'
  		}))
  		.pipe(prettify({indent_size: 2}))
  		.pipe(gulp.dest(DEST));
  });
  
  gulp.task('fonts', function() {
  	return gulp.src(SRC + '/assets/type/**/*')
  		.pipe(gulp.dest(DEST + '/assets/type'));
  });
  
  gulp.task('css', function() {
  	var processors = [
  		cssimport(),
  		autoprefixer({
  			browsers: ['last 2 versions']
  		})
      ];
  	
      return gulp.src(SRC + '/assets/css/style*.css')
  		.pipe(postcss(processors))
  		.pipe(gulp.dest(DEST + '/assets/css'));
  });
  
  gulp.task('default', ['css', 'fonts', 'pages']);
  
subject: Clean up gulpfile