jquery mobile popup close button doesn't always work - jquery-mobile

Question

I'm using jquery mobile 1.4.5. In some instances, I generate a pop-up when a user clicks a link and fill that popup with the results of an ajax call. The generated code taken from firebug after the ajax call returns looks like:
<div id="detailsPopup-popup" class="ui-popup-container ui-popup-active" tabindex="0" style="max-width: 1250px; top: 68.9967px; left: 146px;">
<div id="detailsPopup" class="ui-content ui-popup ui-body-a ui-overlay-shadow ui-corner-all" data-role="popup" style="width: 971.538px;"><a class="ui-btn ui-corner-all ui-shadow ui-btn-a ui-icon-delete ui-btn-icon-notext ui-btn-right" data-iconpos="notext" data-icon="delete" data-theme="a" data-role="button" data-rel="back" href="#">Close</a>
<div data-theme="a" data-role="header">
...content...
</div>
</div>
</div>
The popup is showing up fine. I'd say 90% of the time, when i click the close button, the popup closes. However, 10% of the time it just sits there. Usually it'll highlight the close button as blue, indicating it is active or something but the window itself stays open. If I click around in the popup box a few times and keep trying, it will eventually close, but it is extremely frustrating and user unfriendly.
I'm not sure why it doesn't work that small fraction of the time? I've included a screenshot of what the modal looks like. I don't know if the parent div (the blue outline) is somehow covering half of the button and so that is catching the clicks sometimes?
any thoughts as to what is going on here? I've only been able to try in android/chrome and not an iphone, so i don't know if it is browser specific.
Thanks!
edit: adding javascript code that parses ajax response and generates window. NOTE: i know i'm putting everything in the header div right now (for padding purposes), however I don't think that's causing the issue. I stripped out a lot of the contents of the window for brevity.
function showPopup(jsonResponse){
// parse json response
var obj = jQuery.parseJSON( jsonResponse );
// close button
var closeBtn = $('Close').button();
// start to construct window contents from response
var content = "<div data-role=\"header\" data-theme=\"a\">";
content += '<table border="0" style="width:100%"><tr>';
content += '<td style="vertical-align:top;">';
content += '<a data-ajax="false" href="show.php?id='+obj.id+'"><img src="'+obj.pic+'" style=\"max-height: 2em;\"></a><br><b>'+obj.title+'</b></div>';
content += '</td></tr></table>';
// close header div
content += '</div>';
// Popup body - set width is optional - append button and Ajax msg (was 1.5 width originally)
var popup = $("<div/>", {
"id": "detailsPopup",
"data-role": "popup",
"class": "ui-content"
}).css({
"width": $(window).width() / 1.3 + "px"
}).append(closeBtn).append(content);
// Append it to active page
$(".ui-page-active").append(popup);
// Create it and add listener to delete it once it's closed
// open it
$("#detailsPopup").on("popupafterclose", function () {
$(this).remove();
}).on("popupafteropen", function () {
$(this).popup("reposition", {
"positionTo": "window"
//x: 150,
//y: 200
});
}).popup({
"dismissible": false,
"history": false,
"theme": "a",
"overlayTheme": "b",
"class" : "ui-content"
}).popup("open");
} // end showPopup

Answer 1

ok, so i finally figured it out. was 100% my fault (as expected). i was overriding some default JQM css, and of course it caused the error. on another part of the page i had to try to fit 3 buttons on the same row, and had used the following to do it.
.ui-btn{
font-size:12px;
}
(originally: 1em)
That shrunk the buttons enough to fit that other requirement, but that also caused the close button to not show properly (as you can see below it was missing the outer border). Thus, I'm guessing it was just a weird offset/padding/etc error caused by the differing font-size that was the reason behind the clicks not registering or being handled properly.
(insert advice to never override jqm css)
thanks!