Integrated in angular/typescript

hey sir, thank you for the beatiful animation. I would like to add it to my chatbot written in Angular.
I added this code to ngOnInit():
this.siriWave = new SiriWave({
container: document.querySelector("#myWave"),
cover: true,
height: 100,
style: "ios9"
});

But somehow i 4D09 am getting the error: Failed to execute 'getComputedStyle' on 'Window': parameter 1 is not of type 'Element'. Can you please help me out ?