refactor(ui): make alerts look nicer

Signed-off-by: SphericalKat <amolele@gmail.com>

assets/css/app.css

@@ -30,4 +30,19 @@ code {
 	white-space: pre;
 	font-size: 14px;
 	font-weight: bold;
+}
+
+.alert {
+	width: 100%;
+	text-align: center;
+}
+
+.alert-info {
+	background-color: #1ed98e;
+	color: black;
+}
+
+.alert-danger {
+	background-color: #ff9800;
+	color: black;
 }