Either update the theme you are using or override the message CSS rules, the default theme uses the following rules:
.alertify-notifier .ajs-message {
background: rgba(255, 255, 255, 0.95);
color: #000;
text-align: center;
border: solid 1px #ddd;
border-radius: 2px;
}
.alertify-notifier .ajs-message.ajs-success {
color: #fff;
background: rgba(91, 189, 114, 0.95);
text-shadow: –1px –1px 0 rgba(0, 0, 0, 0.5);
}
.alertify-notifier .ajs-message.ajs-error {
color: #fff;
background: rgba(217, 92, 92, 0.95);
text-shadow: –1px –1px 0 rgba(0, 0, 0, 0.5);
}
.alertify-notifier .ajs-message.ajs-warning {
background: rgba(252, 248, 215, 0.95);
border-color: #999;
}
To change the font color of a specific message type, override it’s corresponding rule:
.alertify-notifier .ajs-message.ajs-success{
color: blue;
}