network_report_server/app/templates/_messages.html

{% if messages %}
    {% for message in messages %}
    <div{% if message.tags %} style='z-index:2000' class="alert alert-{{ message.tags }}  text-center h5 position-absolute top-50 start-50 translate-middle fs-6" {% endif %}>{{ message }}</div>
    {% endfor %}
{% endif %}