How to add and use a custom style class in SAPUI5

I am new to SAPUI5 and would like to change the text color of a label to red. How can I do this.

I tried:

sap.ui.getCore().byId("lableID").setStyleClass("red");

but the color does not change.

>Solution :

You need to add a style.css file under webapp > css to your project. The style.css file could look like this:

.red {
    color: red;
}