login.component.html

<h1 class="title is-4">Login</h1>
<p class="description">Welcome back!</p>
<form (ngSubmit)="login()" [formGroup]="loginForm" novalidate autocomplete="false">
  <div class="field">
    <div class="control">
      <input [ngClass]="{'is-danger': displayMessage.email}" class="input is-medium" type="email" placeholder="Email" formControlName="email">
      <p *ngIf="displayMessage.email" class="help is-danger">
        {{ displayMessage.email }}
      </p>
    </div>
  </div>
  <div class="field">
    <div class="control">
      <input [ngClass]="{'is-danger': displayMessage.password}" class="input is-medium" type="password" placeholder="Password" formControlName="password">
      <p *ngIf="displayMessage.password" class="help is-danger">
        {{ displayMessage.password }}
      </p>
    </div>
  </div>
  <button type="submit" class="button is-block is-primary is-fullwidth is-medium" [disabled]="loginForm.invalid">Login</button>
  <br>
  <small class="has-text-centered">
    <em>
      Don't have an account
      <a [routerLink]="['signup']" class="primary-color">Sign Up</a>
    </em>
  </small>
</form>