lue(`color`, `hwb(from oklch(1 0.399 336.3) h w b)`, `rgb(255, 255, 255)`); // Naive clip based mapping would give rgb(255, 91, 255).
    test_valid_value(`color`, `hwb(from oklch(0 0.399 336.3) h w b)`, `rgb(0, 0, 0)`); // Naive clip based mapping would give rgb(20, 0, 24).

    // Testing replacement with 0.
    test_valid_value(`color`, `hwb(from rebeccapurple 0 0% 0%)`, `rgb(255, 0, 0)`);
    test_valid_value(`color`, `hwb(from rebeccapurple 0deg 0% 0%)`, `rgb(255, 0, 0)`);
    test_valid_value(`color`,