Syntax error, unrecognized expression on box-shadow value on exercise 4

[Ingirorhaun]

The last test of exercise 4 doesn't seem to work correctly. I keep getting a "Syntax error, unrecognized expression" on the box-shadow value, even though the css syntax is correct and the box shadow is visible on the element.

I'm not too familiar with Cypress, but if I rewrite the assertions in the test from:

 cy.get('header').should('exist').and('have.css', 'box-shadow').and('not.contain.value', 'none')
 cy.get('footer').should('exist').and('have.css', 'box-shadow').and('not.contain.value', 'none')

to

cy.get('header').should('exist').and('not.have.css', 'box-shadow', 'none')
cy.get('footer').should('exist').and('not.have.css', 'box-shadow', 'none')

it seems to fix the issue. It still checks that the property exists on the element, but fails if the value is 'none'.