Problem with background img

Hi,i have a strange problem with xdk.When i'll open a new project and use an img for the background of body i can see it with no problems but,when i grab an input type from develope tab magically the img disappear and browser can't read and apply the css' code for background.But,more strange than this,when i delete the input the img still doesn't working.In attachments you can finde the img of prob.