Specific classes using CSS modules not working in React

I can't get CSS modules to work in Js - the plain global CSS module file is working, and so are non-specific classes like body are working, however I can't get classes.className to work for example. I'd be glad of some help/ closure. Thanks,

Edit: I don't have an error upon compiling Edit 2: In Dev Tools no classes are shown unless I declare them statically like "className"

import React from "react";
import '.././Index.module.css';
import classes from "./CardLrg.module.css"


function CardLrg(props) {
    return (
        <div>
            <div className={classes.cardLrg}>
            <div className={classes.cardLrgHead}>
                <div className={classes.cardLrgDiscount}>{props.discount}</div>
                <img src="../../public/plus-square.svg" alt="Add to basket"/>
            </div>
            <div className={classes.cardLrgMainContent}>{props.sku}</div>
        </div>
        </div>
        
    )
}

export default CardLrg

.cardLrg {
    height: 160px;
    width: 160px;
    border-radius: 10px;
    border: 5px solid #000000;
    box-shadow: 10px 10px 0px #000000;
    position: relative;
    background-color: #f7f7f7;
}