JavaScript widget using jquery

This is a reference implementation

by ashraf_zmn

HTML

<h1>Tech Blog feed</h1>
<div data-blog-name="jitu-blog" data-no-css="false" class="blogger-jquery-widget effect6" style="width: 500px; height: 100px;"></div>
<script src="http://jquery-widget.herokuapp.com/assets/application.js" type="text/javascript"></script>

SCSS

.blogger-jquery-widget {

  div, span, object, iframe, h1, h2, h3, h4, h5, h6, p, blockquote, pre, abbr, address, cite, code, del, dfn, em, img, ins, kbd, q, samp, small, strong, sub, sup, var, b, i, dl, dt, dd, ol, ul, li, fieldset, form, label, legend, table, caption, tbody, tfoot, thead, tr, th, td, article, aside, canvas, details, figcaption, figure, footer, header, hgroup, menu, nav, section, summary, time, mark, audio, video {
    margin: 0;
    padding: 0;
    border: 0;
    outline: 0;
    font-size: 100%;
    vertical-align: baseline;
    background: transparent;
    line-height: normal;
    text-align: left;
  }

  ul, li{
    margin: 0 !important;
    padding: 0 !important;
  }

  a {
    background-color: transparent;
    color: #222;
  }

  a:hover {
    background-color: transparent;
    color: #444;
  }

  h1 {
    font-size: 18px;
  }

  span.posted_on {
    color: #888;
    font-size: 16px !important;
  }

  ul.categories {
    color: #333;
    margin-top: 10px !important;

    li {
      font-size: 14px !important;
      margin: 0px 7px 0px 0px !important;
      padding: 3px 7px 1px 7px !important;
      border: 1px;
      float: left;
      display: block;
      border-radius: 5px;
      border: 1px;
      border-color: #000000 !important;
      background-color: #dedede !important;
      text-shadow:#fff 0px 1px 0, #555 0 -1px 0;
    }
  }

  .bx-wrapper {
    margin: 0px;
    padding: 0px;
    overflow: hidden;
    width: inherit !important;
  }

  .bx-window {
    margin: 10px 30px 10px 30px;
    overflow: hidden;
  }

  .bx-prev, .bx-next {
    position: absolute;
    left: 8px;
    background: transparent url(http://tympanus.net/Tutorials/ResponsiveImageGallery/images/nav_thumbs.png) no-repeat top left;
    width: 14px;
    height: 26px;
    margin-top: -13px;
    text-indent: -9000px;
    cursor: pointer;
    opacity: 0.8;
  }

  .bx-prev {
    /*right: 8px;
    left: auto;
    background-position: top right;*/
  }

  .bx-next {
   ...

JavaScript

/*
 * Reference: http://alexmarandon.com/articles/web_widget_jquery/
 * Slider used: http://bxslider.com/examples
 * Shadow effects: http://www.paulund.co.uk/creating-different-css3-box-shadows-effects
 * Blogspot JSON feed: http://beautifulbeta.wikidot.com/json-feeds
 *
 * Usage:
 * Add the following code in the html
 *
 * ------------------------------------------------------------------------------------------------
 * <script src="http://jquery-widget.herokuapp.com/assets/blogger-widget.js" type="text/javascript"></script>
 * <div data-blog-name="jitu-blog" data-no-css="false" class="blogger-jquery-widget effect6"></div>
 * ------------------------------------------------------------------------------------------------
 *
 * */
(function() {
    // Localize jQuery variable
    var jQuery;

    /******** Load jQuery if not present *********/
    if (window.jQuery === undefined) {
        var script_tag = document.createElement('script');
        script_tag.setAttribute("type", "text/javascript");
        script_tag.setAttribute("src", "https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js");
        if (script_tag.readyState) {
            script_tag.onreadystatechange = function() { // For old versions of IE
                if (this.readyState == 'complete' || this.readyState == 'loaded') {
                    scriptLoadHandler();
                }
            };
        } else {
            script_tag.onload = scriptLoadHandler;
        }
        // Try to find the head, otherwise default to the documentElement
        (document.getElementsByTagName("head")[0] || document.documentElement).appendChild(script_tag);
    } else {
        // The jQuery version on the window is the one we want to use
        jQuery = window.jQuery;
        main();
    }

    /******** Called once jQuery has loaded ******/

    function scriptLoadHandler() {
        // Restore $ and window.jQuery to their previous values and store the
        // new jQuery in our local...