code: function copyFiles() {
    return mergeStream(
      // CSS source
      gulp.src([
        'css-components/**/*',
        '!css-components/onsen-visual-design-spec.sketch',
        '!css-components/build/',
        '!css-components/build/**/*',
        '!css-components/node_modules/',
        '!css-components/node_modules/**/*',
        '!css-components/npm-debug.log'
      ])
        .pipe(gulp.dest('build/css-components-src/')),
  
      // These are not used (already loaded by gulp-replace)
      // gulp.src('core/images/**/*')
      //   .pipe(gulp.dest('build/images/')),
  
      // package.json (for the bindings which uses `build` directory)
      gulp.src([
        'package.json',
      ])
        .pipe(gulp.dest('build/')),
  
      // type definitions copy
      gulp.src('core/src/onsenui.d.ts')
        .pipe(gulp.dest('build/js/')),
    );
  }
docs: ////////////////////////////////////// copy-files //////////////////////////////////////