Check if element exist JEST tests

I'm trying to test if sgn.init() after call, generate and append element to DOM. However document.querySelector('.class') seems to always return null, even if I tried to add it manually in test function. Can You tell me what I'm doing wrong?

test('shoud be rendered', () => {
    sgn.init();
    const element = document.createElement('div');
    element.classList.add('.element');
    document.body.appendChild(element);
    console.log(document.querySelector('.element'))

});