LibWeb: Clamp calc()'d shadow blur radius to positive values

Author: https://github.com/Calme1709
Commit: 004bd3dc8f
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/6208
Reviewed-by: https://github.com/AtkinsSJ ✅

Libraries/LibWeb/CSS/Parser/ValueParsing.cpp

@@ -4107,6 +4107,8 @@ RefPtr<StyleValue const> Parser::parse_calculated_value(ComponentValue const& co
             },
             [](SpecialContext special_context) -> Optional<CalculationContext> {
                 switch (special_context) {
+                case SpecialContext::ShadowBlurRadius:
+                    return CalculationContext { .accepted_type_ranges = { { ValueType::Length, { 0, NumericLimits<float>::max() } } } };
                 case SpecialContext::TranslateZArgument:
                     // Percentages are disallowed for the Z axis
                     return CalculationContext {};