为什么我的 angular 步进器没有样式?

Why my angular stepper doesn't have style?

最近我开始使用Angular,我需要创建一个多步骤的表单,首先安装它很麻烦,但最后还是有了,但是当我使用它在我的组件上它根本没有样式,我在很多网站和视频中搜索过,但每个人都和我一样。知道问题出在哪里吗?

这是我的 app.module.ts:

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { HomeComponent } from './home/home.component';
import { DrawingsComponent } from './drawings/drawings.component';
import {HttpClientModule} from '@angular/common/http';
import {FormsModule} from '@angular/forms';
import { MatStepperModule } from '@angular/material/stepper';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
import { MatIconModule } from '@angular/material/icon';
import { MatButtonModule } from '@angular/material/button';
import { MatPseudoCheckboxModule } from '@angular/material/core';

@NgModule({
  declarations: [
    AppComponent,
    HomeComponent,
    DrawingsComponent
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    HttpClientModule,
    FormsModule,
    MatStepperModule,
    MatIconModule,
    MatButtonModule,
    MatPseudoCheckboxModule,
    BrowserAnimationsModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

这是我的例子:

<mat-horizontal-stepper>
  <mat-step label="Step 1">
    Content 1
  </mat-step>
  <mat-step label="Step 1">
    Content 2
  </mat-step>
</mat-horizontal-stepper>

Here is how it should look like

This is how it looks

安装时是否选择了主题angular material?请看一下here