Add Angular Material to Lib in Nx Monorepo

Question

I am trying to view a story of an Angular Material Button. However, in the story, the button does not have any styles. I imported angular material using : ng add angular/material and these ara my files for my component :

This is the html file :

<button mat-button color="primary">Button Material</button>

This is the module of my lib :

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { RouterModule, Route } from '@angular/router';
import { ElementComponent } from './element/element.component';
import {MatButtonModule} from '@angular/material/button';
import { MaterialComponent } from './material/material.component';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';


export const plateRoutes: Route[] = [];

@NgModule({
  imports: [CommonModule, RouterModule,BrowserAnimationsModule, MatButtonModule],
  declarations: [
    ElementComponent,
    MaterialComponent,

  ],
})
export class PlateModule {}

This is the component story :

As you can see the style does not apply to the mat button...