0.7 0.45 30) none none none / none)`,                            `oklch(none none none / none)`);
    test_valid_value(`color`, `oklch(from oklch(0.7 0.45 30) l c none)`,                                         `oklch(0.7 0.45 none)`);
    test_valid_value(`color`, `oklch(from oklch(0.7 0.45 30) l c none / alpha)`,                                 `oklch(0.7 0.45 none)`);
    test_valid_value(`color`, `oklch(from oklch(0.7 0.45 30) l c h / none)`,                                     `oklch(0.7 0.45 30 / none