I have a constant called CLASSES:

const CLASSES = {
    root: "root",
    vertical: "master",
    horizontal: "alternate",
} 

I have a variable gridType which has a value of either a string of vertical or horizontal.

render() {
    const { gridType } = this;  // equals either a string of 'vertica'l or horizontal 


    return html `<div class="${CLASSES.root}"</div>`;
}

How would I add gridType class to the returned html? I can't do <div class="${CLASSES.root} ${CLASSES.gridType}"</div> since gridType is not a value on CLASSES