Background command not displaying/showing from the stylesheet when using date picker js

I'm new to this site having stumbled across it recently (and am loving it!) and was wondering whether someone can help me - I'm using Kelvin Luck's fantastic date picker and for some reason a background image is not behaving properly...

Here's the code straight from my CSS sheet:

a.dp-choose-date {
   background: url (../calendar.png) no-repeat scroll 0 0 transparent;
   display:block;
   float:left;
   height:16px;
   ma开发者_StackOverflowrgin:5px 3px 0;
   overflow:hidden;
   padding:0;
   text-indent:-2000px;
   width:16px;
}

however when the background image is viewed through firebug, firebug doesn't show the style for the background image at all:

a.dp-choose-date {
   display:block;
   float:left;
   height:16px;
   margin:5px 3px 0;
   overflow:hidden;
   padding:0;
   text-indent:-2000px;
   width:16px;
}

Would anyone have any ideas as to why this is happening? I've never seen this before!

The url by the way is http://www.s330042945.websitehome.co.uk/contact.php

Many thanks, Andy

---

You need to remove the space between 'url' and the '('. This needs to be:

background: url(../calendar.png) no-repeat scroll 0 0 transparent;