public static void TransferRulePropertiesToSelector(this StyleSheet toStyleSheet, StyleComplexSelector toSelector, StyleSheet fromStyleSheet, StyleRule fromRule)
        {
            foreach (var property in fromRule.properties)
            {
                var newProperty = toStyleSheet.AddProperty(toSelector, property.name);
                foreach (var value in property.values)
                {
                    switch (value.valueType)
                    {
                    case StyleValueType.Float: toStyleSheet.AddValue(newProperty, fromStyleSheet.GetFloat(value)); break;

#if UNITY_2019_3_OR_NEWER
                    case StyleValueType.Dimension: toStyleSheet.AddValue(newProperty, fromStyleSheet.GetDimension(value)); break;
#endif
                    case StyleValueType.Enum: toStyleSheet.AddValueAsEnum(newProperty, fromStyleSheet.GetEnum(value)); break;

                    case StyleValueType.String: toStyleSheet.AddValue(newProperty, fromStyleSheet.GetString(value)); break;

                    case StyleValueType.Color: toStyleSheet.AddValue(newProperty, fromStyleSheet.GetColor(value)); break;

                    case StyleValueType.AssetReference: toStyleSheet.AddValue(newProperty, fromStyleSheet.GetAsset(value)); break;

                    case StyleValueType.ResourcePath: toStyleSheet.AddValue(newProperty, fromStyleSheet.GetAsset(value)); break;

#if UNITY_2019_3_OR_NEWER // UNITY_BUILDER_VARIABLE_SUPPORT
                    case StyleValueType.Variable: toStyleSheet.AddVariable(newProperty, fromStyleSheet.GetString(value)); break;
#endif
                    }
                }
            }
            foreach (var property in fromRule.properties)
            {
                fromStyleSheet.RemoveProperty(fromRule, property);
            }
        }
 StyleValueHandle[] AddVariableToStyleSheet(string variableName)
 {
     return(styleSheet.AddVariable(styleProperty, variableName));
 }