Jasmine jQuery testing mouse enter

I am new to jasmine and jquery / javascript so I not sure what I am doing wrong here can you please help me. It seems it don't find the DOM element and can't perform the expect correktly.

describe('ClickFunctions', function () {

    beforeEach(function () {
        jasmine.getFixtures().fixturesPath = 'src/test/js/fixtures';
        loadFixtures('Click.html');
    });

    it('should change the css on mouseenter of step-header',function () {

        var step = $('#Step_1');

        step.trigger('mouseenter');

        expect(step).toHaveCss({
            'background-color': '#D9EDF7'
        })

    });
});