Banner image not showing in Chrome

Hi everyone,

I have created a banner which has a logo in it and uploaded it into my images folder.  I have created a new css document and saved that in my style library which refers to the banner I created:-

.ribbonbackground, .s4-title {
background:url('http://spdev.xwwl.nhs.uk/sites/BI/PublishingImages/SiteBanner7.png') no-repeat 0 0 !important;
} 

I then made reference to this css file in the Site Master Page Settings on my site under alternative css URL.

The banner is showing correctly in internet explorer but the image in the banner isn't showing when I view the site on Chrome.

Does anyone knowthe solution to get it to show in Chrome?

Many thanks for your help

Natalie

xXx