Similar Codes, Different Effect

[bonesinc]

I am a beginner in designer, I had to develop a small website, where i designed a ui, but i have problems regarding css.Here's a style i have written \[code\]background-image: url("../images/border_bottom_left.png"), url("../images/border_bottom_right.png"), url("../images/border_top_left.png"), url("../images/border_top_right.png");background-position: bottom left, bottom right, top left, top right;background-color:grey;background-repeat: no-repeat;\[/code\]which inserts four images to four corners and fills all the other part with a grey backgroundNow, instead of grey, i wanted to insert an image, So i replaced \[code\]background-color\[/code\] with \[code\]background-image: url("../images/bg_content.png")\[/code\] but it does not help me. I tried to use the \[code\]bg_content.png\[/code\] in the first \[code\]background-image\[/code\] and write its corresponding position to \[code\]center\[/code\], it didn't work?Can anyone of you please help me!