mobile version issue

Hi,

Originally front page was cutting off the pictures of my slide show so i used a code on my custom css to have full size of my picture in mobile version but it has white spaces on top and button of the page. could you guys please help me on it?

https://www.nazemibridal.com

the code that i uses is as bellow:

@media only screen and (max-width: 700px){
#slideshow{
height: 500 !important;
}
.slides-container .slide-item{
background-size: 100% !important;
}
}

Thank you in advance.