child them mobile css not working

Hi Guys,

I’m currently updating my theme to use a child theme and I can’t get my Mobile style working. I have the following code in the child theme style.css and it’s just not working. This was working perfectly fine in 2.8 which I have upgraded form to the latest version. Any Ideas?

http://animationink.com.au/major/

@media only screen and (max-width: 767px) {
/* Add your Mobile Styles here */
.ls-wp-fullwidth-container{ display: none !important; }
/* Hide main catorgy image on mobile*/
.home a.avia_image.avia-builder-el-6.el_before_av_heading.avia-builder-el-first.avia-align-center { display: none; }
.home a.avia_image.avia-builder-el-10.el_before_av_heading.avia-builder-el-first.avia-align-center { display: none; }
.home a.avia_image.avia-builder-el-14.el_before_av_heading.avia-builder-el-first.avia-align-center { display: none; }
.home a.avia_image.avia-builder-el-18.el_before_av_heading.avia-builder-el-first.avia-align-center { display: none; }
.home a.avia_image.avia-builder-el-22.el_before_av_heading.avia-builder-el-first.avia-align-center { display: none; }
/* Hide Info News */
.home div.flex_column.av_two_third.first.avia-builder-el-25 { display: none; }
/* Hide Info Selection */
.home div.flex_column.av_one_third.avia-builder-el-28 { display: none; }
/* Hide Major About */
.home div.flex_column.av_one_full.first.avia-builder-el-37 { display: none; }
/* Hide them by default */
#mobilebuttons{ display: none;}
#mobilenews{ display: none;}

/* Show them only on mobile and hide the existing ones */
#mobilebuttons{ display: block; }
#mobilenews{ display: block; }
}