d_value(`color`, `lch(from lch(0.7 45 30) l c 0deg / alpha)`, `lch(0.7 45 0)`);
    test_valid_value(`color`, `lch(from lch(0.7 45 30) l c h / 0)`, `lch(0.7 45 30 / 0)`);
    test_valid_value(`color`, `lch(from lch(0.7 45 30 / 40%) 0 c h / alpha)`, `lch(0 45 30 / 0.4)`);
    test_valid_value(`color`, `lch(from lch(0.7 45 30 / 40%) l 0 h / alpha)`, `lch(0.7 0 30 / 0.4)`);
    test_valid_value(`color`, `lch(from lch(0.7 45 30 / 40%) l c 0 / alpha)`, `lch(0.7 45 0 / 0.4)`);
    test_valid_value(`color`, `lch(f