Style alerts

src/app/app.component.scss

@@ -15,10 +15,6 @@ min-height: 100vh;
     flex: 1;
 }
 
-.selected {
-    font-weight: 600;
-}
-
 .footer {
     display: flex;
     flex-direction: row;

src/app/components/alert/alert.component.html

@@ -1,6 +1,7 @@
 <h3>Send an Alert</h3>
+<form #alertForm="ngForm">
   <mat-form-field>
-  <input matInput [(ngModel)]="alert" type="text" placeholder="Alert"></mat-form-field>
-<div>
-<button mat-raised-button color="warn" (click)="onSubmit()">Send</button>
-</div>
+    <input matInput [(ngModel)]="alert" type="text" name="alert" placeholder="Alert" required>
+  </mat-form-field>
+  <button mat-raised-button color="primary" id="sendButton" [disabled]="!alertForm.form.valid" (click)="onSubmit()">Send</button>
+</form>

src/app/components/alert/alert.component.scss

@@ -0,0 +1,7 @@
+mat-form-field {
+    width: 100%;
+}
+
+#sendButton {
+    width: 100%;
+}