关于灯箱内容的jquery

I have a page where lightbox/popup is triggered through a class-name. So lightbox/popup is triggered through class "os-trigger-booking" on anchor tag. Now i have some customized jquery but they are working on the page, but when i target some elements of lightbox through jquery they does not work on lightbox.

Lightbox is opened when the button is clicked.

This is button html

<div class="avia-button-wrap avia-button-center  os_trigger_booking aquagold" data-selected-service="59">

<a href="" class="avia-button av-icon-on-hover  avia-icon_select-yes-right-icon avia-color-custom avia-size-x-large avia-position-center " style="background-color:#5b4541; border-color:#5b4541; color:#ffffff; " onclick="trackevent1()">

<span class="avia_iconbox_title">Book Your AQUAGOLD® Appointment</span>

<span class="avia_button_icon avia_button_icon_right" aria-hidden="true" data-av_icon="" data-av_iconfont="entypo-fontello"></span>

</a>

</div>

This is lightbox html - overview

<div class="lightbox-w">
<div class="step-payment-w">
<span>xyz</span>
</div>
<div class="step-verify-w">
<span>abc</span>
</div>
<a href="#" class="latepoint-next-btn"></a>
</div>

<script>

jQuery(document).ready(function( $ ){
      $('.av-special-heading').eq(0).addClass('first-heading');
      var someValue = 59; 
      $('.aquagold').attr('data-selected-service', someValue);
      $('div.os_trigger_booking.aquagold' ).children('.avia-button').attr('onclick', 'trackevent1()');

      //BELOW ARE THE CLASSES OF ELEMENTS INSIDE LIGHTBOX AND NOT TARGETTING

      if ($('.step-verify-w').length > 0) {  
      $('.latepoint-next-btn').css('background-color', 'red');
      }
      });
</script>

</div>