JSON CSS parser

我的递归函数坏了，我不知道为什么。我正试图用barebone javascript编写json到css的解析器，似乎无法将我的头围绕为什么我的函数不起作用。有人能帮我一下吗?

在css中，你会得到你正在寻址的特定元素的子元素，比如

#nav li{
  some style here
}

试图在javascript中操作相同的东西，但它不起作用。到目前为止，我的代码对于简单的选择器工作得很好。

var json = {
    "body" : {
        "background": "#303030",
        "color": "#FFFFFF",
        "font-family": "Arial, Helvetica, sans-serif"
    },
    "#nav": {
        "li": {
            "display": "inline-block",
            "list-styles": "none",
            "margin-right": "10px",
            "padding": "10px, 10px"
        }
    }
}
// How to use:
// json is an obj
// body is a selector
// background is a property belong to a selector
// #303030 is a value for the property

//apply css changes to document without writing any css
//by default the first values are
//               selector = background
//               parent   = document
//               object   = json
function styleApply(selector, parent, object){
    var element, onSelector, signal;
    //checks the first character of the selector and grabs element from page depending on what type of element it is
    switch(selector[0]){
        case ".":
            element= parent.getElementsByClassName(selector.substring(1));
            newParent = element[0]; //checks to see what is in the first index of the obtained element
            break;
        case "#":
            element= parent.getElementById(selector.substring(1));
            newParent = element;
            break;
        default:
            element= parent.getElementsByTagName(selector);
            newParent = element[0];
            break;
    }
    //only works if there is actually an element in the page corresponding with the selector
    if(newParent != null){ 
        //loops through all elements with the same selector or in the case of id just does one loop
        for(var i=0; i<element.length; i++){ 
            //loops through all properties in the selector
            for (var property in object[selector]){
                //grabs the associated value with the selector could be string or object
                var value= object[selector][property];
                //if it is a string it is a style, if it is an object, it is targeting the elements inside the current selector only
                if(typeof(value) === "string"){
                    element[i].style.setProperty(property, value);
                }else{
/*I am breaking my code right here*/
                    //reusing the same function, this time selector is equal to property for the case of nav, it is the element 'li'
                    //newParent is the element who is a parent of the current element (e.g 'nav' is parent of 'li')
                    //value is the new object that is replacing json, 
                    styleApply(property, newParent, value); //since value is an object it did not pass the string test and now the new object is value
/*Problem ends here */

                }
            }
        }
    } 
}
my code for looping over all the values in json
for (var selector in json){
    styleApply(selector, document, json);
}