Multiple classes:
<div class="user--status"
[ngClass]="{
'user--status-active': user?.status === 'active',
'user--status-inactive': user?.status === 'inactive'
}">
{{ user?.status }}
</div>
Conditional class:
<div class="user--status"
[ngClass]="user?.status == 'active' ? 'user--status-active' : 'user--status-inactive'">
{{ user?.status }}
</div>