Fixed top menu - how to disable on mobile devices

[zabamich]

I have made Fixed top menu for my store, all is great except mobile devices. how to keep fixed top menu for pc browser and switch off on mobile devices??
any idea

 

I used in global.css

 

 

header {

  z-index: 1;

  position: fixed;

  background: white;

  padding-bottom: 15px;

  width: 100%; }

 

to create fixed top menu