How do you access a HTML element on the DOM from a class constructor in a JavaScript module?

I simply want to access this div

 <div class="loadingBar"></div>

Here is my module:

export default class LoadingBar
       {
        constructor(overlayGeometry, overlayMaterial,LoadingBarElement)
       {
       this.experience = new Experience()
       this.scene = this.experience.scene

    
       this.LoadingBarElement = document.querySelector('./index.html/loadingBar')
       console.log(LoadingBarElement)......

what am I doing wrong?