How to color important stuff?

[pyromaniac3010]

Is it possible to use colors? I tried the following config but it did not work as expected:

templates:
  message.tmpl: |
    {{- if ne .Status "Resolved" -}}<font color=#FF0000>{{- else -}}<font color=#00FF00>{{- end -}}*({{.Labels.severity | toUpper }}) {{ .Labels.alertname | Title }} - {{.Status | Title }}*</font>
    {{ range .Annotations.SortedPairs -}}
    {{ .Name | Title }}: {{ .Value}}
    {{ end -}}

This results in this: