Layout of my intranet website was change when I access it on different computers

[newphpcoder]

Good day!
I created my website on my computer and now I put it on my testing server and I found out that the size background of my website was change even I used those css code:

<style type="text/css">
html,body{
overflow:hidden;
}
BODY {
background-image: url(bground.png);
background-attachment: fixed;
}
</style>

I used those codes to fixed the background but my problem is the background was doubled the image although it is fixed. Not only was the background change also the content of my website was dislocated. I want is only one output should be display in all computers.

It is possible that my website display should be dependent on the browser or the settings of the computer? So those in all computers the display of my website are all the same like what I browse in the internet?

On my used computers my website display is good, but when I try to other computers it was display not so good I don’t know why. I need to fix it now because all the staff wants to see my website… I hope you can help me…
Thank you

[newphpcoder]

Good day!
I research on internet about auto fit of website or adapting the resolution of the monitor or screen of computer, but I can’t find the solution. I want is in any settings/resolution/size of monitor my website appearance was not change. Because now I got a problem that I can’t upload my website in a server because I notice that in other computer my website display was change or change the location of the content of my website, After I noticed that the background was doubled I put the background no repeat and after that on the below of webpage I see a white color.

Here is my css codes:

<style type="text/css"> 
html,body{
overflow:hidden;
}
BODY { 
background-image: url(layout_image/bgroundv09.png);
background-attachment: fixed; 
} 
--> 
</style>

<style type="text/css">

#ddcolortabs{
margin-left: 2px;
padding: 0;
width: 100%;
background: transparent;
voice-family: "\"}\"";
voice-family: inherit;
padding-left: 2px;
}

#ddcolortabs ul{
font: bold 12px Arial, Verdana, sans-serif;
margin:0;
padding:0;
list-style:none;
}

#ddcolortabs li{
display:inline;
margin:0 2px 0 0;
padding:0;
text-transform:uppercase;
}

#ddcolortabs a{
float:right;
color: white;
background: #8cb85c url(layout_image/color_tabs_left.gif) no-repeat left top;
margin:115px 2px 0 0;
padding:0 0 1px 3px;
text-decoration:none;
letter-spacing: 1px;
}

#ddcolortabs a span{
float:right;
display:block;
/*background: transparent url(layout_image/color_tabs_right.gif) no-repeat right top;*/
padding:6px 9px 2px 6px;
}

#ddcolortabs a span{
float:none;
}

#ddcolortabs a:hover{
background-color: #678b3f;
}

#ddcolortabs a:hover span{
background-color: #678b3f ;
}

#ddcolortabs #current a, #ddcolortabs #current span{ /*currently selected tab*/
background-color: #678b3f;
}
</style>
<style type="text/css">

#Layer1_background_green {
	position:absolute;
	width:980px;
	height:392px;
	z-index:1;
	top: 149px;
	left: 0px;
}
#Layer1_vertical_line {
	position:absolute;
	width:3px;
	height:387px;
	z-index:2;
	left: 170px;
	top: 153px;
}
#Layer4_horizontal_line {
	position:absolute;
	width:980px;
	height:5px;
	z-index:3;
	left: 0px;
	top: 150px;
}
#visionmission_flash {
	position:absolute;
	width:644px;
	height:404px;
	z-index:5;
	left: 270px;
	top: 156px;
}
#green_frame {
	position:absolute;
	width:172px;
	height:385px;
	z-index:6;
	left: 0px;
	top: 156px;
}
#nav_vertical {
	position:absolute;
	width:165px;
	height:111px;
	z-index:7;
	left: 10px;
	top: 363px;
}

#nav_vertical ul{
font: bold 12px Arial, Verdana, sans-serif;
margin:0;
padding:0;
list-style:none;
}

#nav_vertical li{
display:inline;
margin:0 0 0 0;
padding:0;
text-transform:uppercase;
}


#nav_vertical a{
float:left;
color: green;
/*background: #8cb85c url(layout_image/color_tabs_left.gif) no-repeat left top;*/
margin:0 2px 0 0;
padding:0 0 1px 3px;
text-decoration:none;
letter-spacing: 1px;
}

#nav_vertical a span{
float:left;
display:block;
/*background: transparent url(layout_image/color_tabs_right.gif) no-repeat right top;*/
padding:9px 9px 2px 6px;
}


#nav_vertical a:hover{
color:#00CC00;
}

#nav_vertical a:hover span{
color: #00CC00 ;
}

#nav_vertical #current a, #nav_vertical #current span{ /*currently selected tab*/
/*background-color: #678b3f; */
color:#FFFFFF
}
#ds {
	position:absolute;
	width:73px;
	height:72px;
	z-index:8;
	left: 0px;
	top: 160px;
}
</style>

Thank you….