JQuery filter on page with highlights

css

.hidden {
  display: none!important;
}
mark {    
    background-color: #fcf8e3;
    padding: 0.2em 0;
}

html

<!-- searh form ... -->
<input type="text" id="Query" class="form-control" onkeyup="onSearch();" placeholder="Search..." />
<!-- markup sample -->
<div class="exception">....</div>
<div class="exception">....</div>
<div class="exception">....</div>
<div class="exception">....</div>
<div class="exception">....</div>
<div class="exception">....</div>
<div class="exception">....</div>

js

$(document).ready(function () {
    $.extend($.expr[":"], {
        "containsCI": function (elem, i, match, array) {
            return (elem.textContent || elem.innerText || "").toLowerCase().indexOf((match[3] || "").toLowerCase()) >= 0;
        }
    });
    $.extend($.expr[":"], {
        "notContainsCI": function (elem, i, match, array) {
            return (elem.textContent || elem.innerText || "").toLowerCase().indexOf((match[3] || "").toLowerCase()) < 0;
        }
    });
    function onSearch() {
        var query = $('#Query').val();
        $(".exception:notContainsCI('" + query + "')").addClass('hidden');
        $(".exception:containsCI('" + query + "')").removeClass('hidden');
        //++++++++++++
        //clear all marks
        $(".exception").not(".hidden").each(function () {
            var html = this.innerHTML;
            html = html.replace(new RegExp("(<mark>)([^<>]*)(<\\/mark>)", "gi"), "$2");
            this.innerHTML = html;
        });
        //highlight text, 3 chars threshold
        if (query.trim().length > 2) {
            $(".exception").not('.hidden').each(function () {
                var html = this.innerHTML;
                //match only plain text, skip tag declarations, case insensitive, wrap exact matches with <mark> tag
                //Regexp worth PhD in Computer Science
                var re = new RegExp("(<[\\w]+[^>]*>)([^<>]*(" + query + ")[^<>]*)+(<\\/[\\w]+>)", "gi");
                html = html.replace(re, function (match, submatch1, submatch2, submatch3, submatch4) {
                    //submatch2 is a full text inside the tag with possible multiple 'query' matches, replace them all
                    submatch2 = submatch2.replace(new RegExp("(" + query + ")", "gi"), "<mark>$1</mark>");
                    //omit submatch3
                    return submatch1 + submatch2 + submatch4;
                });
                this.innerHTML = html;
            });
        }
    }
    window.onSearch = onSearch;
}