I using fancy box with my photo gallery, the problem is found it upload 2 images. one for the Thumbnail and one for fancy box

<a style="display: block;" class="fancybox imgContainer" href="images/lorenteJerome_barcelona.jpg" data-fancybox-group="gallery" data-filter="arch"><img src="images/lorenteJerome_barcelona.jpg" alt=""></a>

any way , I can upload 1 pic but I need to re-size the Thumbnail image with css or jquery. any one can help .

CSS of the Thumbnail :

.imgContainer {
  width: 100px;
  height: 100px;
  overflow: hidden;
  text-align: center;
  margin: 10px 20px 10px 0;
  float: left;
  border: solid 1px #999;
  display: block;
}