Enquire of Product Finder layout in mobile device

Hi,

Could anyone tell me how to modify the layout of Product finder in mobile device?
My site address is www.shunshinghk.com/test
The questionnaire page(which named "advanced search" in my site) cannot resize like other pages.
Please advise how to solve this.

Thank you~

Also the other pages does not adapt to mobile devices (or to different screen sizes).

The following statement:
.avatar-wrapper {
margin: auto;
width: 1000px;
}
sets the width of the content area of your site to 1000px.