mempool/frontend/src/app/components/search-form/search-form.component.html

<form [formGroup]="searchForm" (submit)="searchForm.valid && search()" class="mr-4" novalidate>
  <div class="form-row">
    <div style="width: 350px;" class="mr-2">
      <input formControlName="searchText" type="text" class="form-control" placeholder="Transaction, address, block hash...">
    </div>
    <div>
      <button type="submit" class="btn btn-block btn-primary">Search</button>
    </div>
  </div>
</form>