Сборка модуля не удалась:.placeholder не определен webpack3.8.1 angular/cli1.5.0

Question

Я использую webpack3.8.1 для компиляции проекта внешнего интерфейса angular5.0, использую angular / cli ^ 1.5.0, мой код приведен ниже, почему при компиляции webpack выдается ошибка '.placeholder недостаточно определено'? webpack.config.js

module: {
    rules: [
      // { test: /\.css$/, use: ['style-loader', 'css-loader'] },
      { test: /\.ts$/, use: [
          {
            loader: 'ts-loader', 
            options: {
              transpileOnly: true
            }
          }
        ] },
      { test: /\.less$/, use: [{ loader: "style-loader" }, { loader: "css-loader" }, { loader: "less-loader" }] },
      { test: /\.(woff|woff2|eot|ttf|otf)$/, use: [ 'file-loader' ]}
    ]
  },

app.less

@import "../../bower_components/bootstrap/less/bootstrap.less";
@import "mixins.less";
@import "variables.less";
@import "carepilot-base.less";

carepilot-base.less

html {
    height: 100%;
    font-family:  @app-font;
    font-size: @font-size;

    @media screen and (max-width: @screen-sm-max) {
        font-size: @font-size-mobile;
    }

    body {
        height: 100%;
        width: 100%;
        color: @dark-blue;
        font-family:  @app-font;
        font-size: @font-size;
        background: @carolina-blue;
        .placeholder(@light-grey, 1.2rem, 500);

        @media screen and (max-width: @screen-sm-max) {
            font-size: @font-size-mobile;
        }

        pageslide {
            background: @dark-blue;

            &.white {
                background: @white;
            }
        }
        input:-webkit-autofill,
        input:-webkit-autofill:hover,
        input:-webkit-autofill:focus,
        input:-webkit-autofill:active {
            transition: background-color 5000s ease-in-out 0s;
        }
    }

Запустите команду 'ng build' Ошибка ниже:

ERROR in ./node_modules/css-loader?{"sourceMap":false,"importLoaders":1}!./node_modules/postcss-loader?{"ident":"postcss"}!./node_modules/less-loader/dist/cjs.js?{"sourceMap":false}!./client/styles/carepilot-base.less
Module build failed:

                background: @carolina-blue;
                .placeholder(@light-grey, 1.2rem, 500);
^
.placeholder is undefined
      in C:\workspace\del\carepilot-web\client\styles\carepilot-base.less (line 23, column 2)
 @ ./client/styles/carepilot-base.less 4:14-202
 @ multi ./client/styles/variables.less ./client/styles/app.less ./client/styles/carepilot-base.less ./client/styles/carepilot.less ./client/styles/icons.less ./client/styles/mixins.less ./client/styles/print.less

Может кто-нибудь мне помочь? Спасибо