I really need help. It is already 5 days I am working on this problem. On FireFox my website's header (logo) is not on center. I don't know which part of stylsheet.css should I edit. This is my stylsheet.css

/**

* Main CSS Stylesheet

*

* @package templateSystem

* @copyright Copyright 2003-2006 Zen Cart Development Team

* @copyright Portions Copyright 2003 osCommerce

* @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0

* @version $Id: stylesheet.css 4387 2006-09-04 13:54:28Z drbyte $

*/



body {

margin: 0;

font-family: verdana, arial, helvetica, sans-serif;

font-size: 62.5%;

background-color: #000000;

color: #ffffff;

}



a img {border: none; }



a:link, #navEZPagesTOC ul li a {

color: #ffffff;

text-decoration: none;

}



a:visited {

color: #ffffff;

text-decoration: none;

}



a:hover, #navEZPagesTOC ul li a:hover, #navMain ul li a:hover, #navSupp ul li a:hover, #navCatTabs ul li a:hover {

color:#8B8C87;

}



a:active {

color: #ffffff;

}



h1 {

font-size: 1.5em;

color: #ffffff;

}



h2 {

font-size: 1.4em;

}



h3 {

font-size: 1.3em;

}



h4, h5, h6, LABEL, h4.optionName, LEGEND, ADDRESS, .sideBoxContent, .larger{

font-size: 1.1em;

}



.biggerText {

font-size: 11px;

font-family: arial;

color: #ffffff;

}



h1, h2, h3, h4, h5, h6 {

margin: 0.3em 0;

}



/* Might uncomment either or both of these if having problems with IE peekaboo bug:

h1, h2, h3, h4, h5, h6, p {

position: relative;

}

*html .centerColumn {

height: 1%;

}

*/



CODE {

font-family: arial, verdana, helvetica, sans-serif;

font-size: 1em;

}



FORM, SELECT, INPUT {

display: inline;

font-size: 1em;

margin: 0.1em;

}



TEXTAREA {

float: left;

margin: auto;

display: block;

width: 95%;

}



input:focus, select:focus, textarea:focus {

background: #E4FEF5;

}



FIELDSET {

padding: 0.5em;

margin: 0.5em 0em;

border: 1px solid #cccccc;

}



LEGEND {

font-weight: bold;

padding: 0.3em;

}



LABEL, h4.optionName {

line-height: 1.5em;

padding: 0.2em;

}



LABEL.checkboxLabel, LABEL.radioButtonLabel {

margin: 0.5em 0.3em;

}



#logo, .centerBoxContents, .specialsListBoxContents, .categoryListBoxContents, .centerBoxContentsAlsoPurch, .attribImg {

float: left;

}



LABEL.inputLabel {

width: 9em;

float: left;

}



LABEL.inputLabelPayment {

width: 14em;

float: left;

padding-left: 2.5em;

}



LABEL.selectLabel, LABEL.switchedLabel, LABEL.uploadsLabel {

width: 11em;

float: left;

}



#checkoutPayment LABEL.radioButtonLabel {

font-weight: bold;

}



P, ADDRESS {

padding: 0.5em;

}



ADDRESS {

font-style: normal;

}



.clearBoth {

clear: both;

}



HR {

height: 1px;

margin-top: 0.5em;

border: none;

border-bottom: 1px solid #9a9a9a;

}



/*warnings, errors, messages*/

.messageStackWarning, .messageStackError, .messageStackSuccess, .messageStackCaution {

line-height: 1.8em;

padding: 0.2em;

border: 1px solid #9a9a9a;

}



.messageStackWarning, .messageStackError {

background-color: #ff0000;

color: #000000;

}



.messageStackSuccess {

background-color: #99FF99;

color: #000000;

}



.messageStackCaution {

background-color: #FFFF66;

color: #000000;

}



/*wrappers - page or section containers*/

#mainWrapper {

background-color: #000000;

text-align: left;

width: 100%;

vertical-align: top;

border: 1px solid #9a9a9a;

}



#headerWrapper, #contentMainWrapper, #logoWrapper, #cartBoxListWrapper, #ezPageBoxList, #cartBoxListWrapper ul, #ezPageBoxList ul, #mainWrapper, #popupAdditionalImage, #popupImage {

margin: 0em;

padding: 0em;

}



#logoWrapper{

background-image: url(../images/header_bg.jpg);

background-repeat: repeat-x;

background-color: #000000;

height:75px;

}



#navColumnOneWrapper, #navColumnTwoWrapper, #mainWrapper {

margin: auto;

}

#navColumnOneWrapper, #navColumnTwoWrapper {

margin-left: 0.5em;

margin-right: 0.5em;

}



#tagline {

color:#000000;

font-size: 2em;

text-align : center;

vertical-align: middle;

}



#sendSpendWrapper {

border: 1px solid #cacaca;

float: right;

margin: 0em 0em 1em 1em;

}



.floatingBox, #accountLinksWrapper, #sendSpendWrapper, #checkoutShipto, #checkoutBillto, #navEZPagesTOCWrapper {

font-family: arial;

font-size: 11px;

color: #ffffff;

margin: 0;

width: 47%;

}



.wrapperAttribsOptions {

margin: 0.3em 0em;

}



/*navigation*/



.navSplitPagesResult {}

.navSplitPagesLinks {}



.navNextPrevCounter {

margin: 0em;

font-size: 0.9em;

}

.navNextPrevList {

display: inline;

white-space: nowrap;

margin: 0;

padding: 0.5em 0em;

list-style-type: none;

}



#navMainWrapper, #navSuppWrapper, #navCatTabsWrapper {

margin: 0em;

background-color: #abbbd3;

background-image: url(../images/tile_back.gif);

padding: 0.5em 0.2em;

font-weight: bold;

color: #;

height: 1%;

}



#navCatTabsWrapper {

background-color: #000000;

color: #9a9a9a;

background-image:none;

}



#navMain ul, #navSupp ul, #navCatTabs ul {

margin: 0;

padding: 0.5em 0em;

list-style-type: none;

text-align: center;

line-height: 1.5em;

}



#navMain ul li, #navSupp ul li, #navCatTabs ul li {

display: inline;

}



#navMain ul li a, #navSupp ul li a, #navCatTabs ul li a {

text-decoration: none;

padding: 0em 0.5em;

margin: 0;

color: #000000;

white-space: nowrap;

}



#navCatTabs ul li a {

color: #9a9a9a;

}



#navEZPagesTOCWrapper {

font-weight: bold;

float: right;

height: 1%;

border: 1px solid #9a9a9a;

}



#navEZPagesTOC ul {

margin: 0;

padding: 0.5em 0em;

list-style-type: none;

line-height: 1.5em;

}



#navEZPagesTOC ul li {

white-space: nowrap;

}



#navEZPagesTOC ul li a {

padding: 0em 0.5em;

margin: 0;

}



#navMainSearch, #navCategoryIcon, .buttonRow, #indexProductListCatDescription {

margin: 0.5em;

}



#navBreadCrumb {

padding: 0.5em 0.5em;

margin: 1px;

background-color: #000000;

font-size: 0.95em;

font-weight: bold;

margin: 0em;

}



#navEZPagesTop {

background-color: #abbbd3;

background-image: url(../images/tile_back.gif);

font-size: 0.95em;

font-weight: bold;

margin: 0em;

padding: 0.5em;

}



#navColumnOne, #navColumnTwo {

background-color: transparent;

}



/*The main content classes*/

#contentColumnMain, #navColumnOne, #navColumnTwo, .centerBoxContents, .specialsListBoxContents, .categoryListBoxContents, .additionalImages, .centerBoxContentsSpecials, .centerBoxContentsAlsoPurch, .centerBoxContentsFeatured, .centerBoxContentsNew, .alert {

vertical-align: top;

}



/*.content,*/ #productDescription, .shippingEstimatorWrapper {

/*font-size: 1.2em;*/

padding: 0.5em;

}



.alert {

color: #FF0000;

margin-left: 0.5em;

}

.advisory {}

.important {

font-weight: bold;

}

.notice {}

.rating{}

.gvBal {

float: right;

}

.centerColumn, #bannerOne, #bannerTwo, #bannerThree, #bannerFour, #bannerFive, #bannerSix {

padding: 0.8em;

}

.centerColumn h1, .centerColumn h2 a{

color:#ffffff;

}

.centerColumn h2 a:hover{

color:#8B8C87;

}

.smallText, #siteinfoLegal, #siteinfoCredits, #siteinfoStatus, #siteinfoIP {

font-size: 0.9em;

}



/*Shopping Cart Display*/

#cartAdd {

float: right;

text-align: center;

margin: 1em;

border: 1px solid #000000;

padding: 1em;

}



.tableHeading TH {

border-bottom: 1px solid #9a9a9a;

}



.tableHeading, #cartSubTotal {

background-color: #e9e9e9;

}



#cartSubTotal {

border-top: 1px solid #cccccc;

font-weight: bold;

text-align: right;

line-height: 2.2em;

padding-right: 2.5em;

}



.tableRow, .tableHeading, #cartSubTotal {

height: 2.2em;

}



.cartProductDisplay, .cartUnitDisplay, .cartTotalDisplay, .cartRemoveItemDisplay, .cartQuantityUpdate, .cartQuantity, #cartInstructionsDisplay, .cartTotalsDisplay {

padding: 0.5em 0em;

}



.cartUnitDisplay, .cartTotalDisplay {

text-align: right;

padding-right: 0.2em;

}



#scUpdateQuantity {

width: 2em;

}



.cartQuantity {

width: 4.7em;

}



.cartNewItem {

color: #33CC33;

position: relative; /*do not remove-fixes stupid IEbug*/

}



.cartOldItem {

color: #660099;

position: relative; /*do not remove-fixes stupid IEbug*/

}



.cartBoxTotal {

text-align: right;

font-weight: bold;

}



.cartRemoveItemDisplay {

width: 3.5em;

}



.cartAttribsList {

margin-left: 1em;

}



#mediaManager {

width: 50%;

margin: 0.2em;

padding: 0.5em;

background-color: #E4FEf5;

border: 1px solid #003D00;

}



.normalprice, .productSpecialPrice, .productSpecialPriceSale {

text-decoration: line-through;

color :#ffffff;

}



.productSalePrice,.productPriceDiscount {

color: #ff0000;

}



.orderHistList {

margin: 1em;

padding: 0.2em 0em;

list-style-type: none;

}



#cartBoxListWrapper ul, #ezPageBoxList ul {

list-style-type: none;

}



#cartBoxListWrapper li, #ezPageBoxList li, .cartBoxTotal {

margin: 0;

padding: 0.2em 0em;

}



#cartBoxEmpty, #cartBoxVoucherBalance {

font-weight: bold;

}



.totalBox {

width: 5.5em;

text-align: right;

padding: 0.2em;

}



.lineTitle, .amount {

text-align: right;

padding: 0.2em;

}



.amount {

width: 5.5em;

}



/*Image Display*/

#productMainImage, #reviewsInfoDefaultProductImage, #productReviewsDefaultProductImage, #reviewWriteMainImage {

margin: 0em 1em 1em 0em ;

}



.categoryIcon {}



#cartImage {

margin: 0.5em 1em;

}



/*Attributes*/

.attribImg {

width: 20%;

margin: 0.3em 0em;

}



.attributesComments {}



/*list box contents*/

.centerBoxContents, .specialsListBoxContents, .categoryListBoxContents, .additionalImages, .centerBoxContentsSpecials, .centerBoxContentsAlsoPurch, .centerBoxContentsFeatured, .centerBoxContentsNew {

margin: 1em 0em;

}



.centerBoxWrapper {

/* border: 1px solid #9a9a9a;

*/



height: 1%;

margin: 1.1em 0;

}



<!--

.style1 {color: #000000}

-->



h2.centerBoxHeading {

font-size: 1.3em;

color: #ffffff;

}



/*sideboxes*/

.columnLeft {}



h3.leftBoxHeading, h3.leftBoxHeading a, div.leftBoxContainer h3.leftBoxHeading, h3.leftBoxHeading label{

font-family: Arial;

font-size: 11px;

color:#ffffff;

font-weight: bold;

text-transform:uppercase;



}



div.rightBoxContainer div.sideBoxContent ul li a:link, div.rightBoxContainer div.sideBoxContent ul li a:visited,

div.rightBoxContainer div.sideBoxContent a:link, div.rightBoxContainer div.sideBoxContent a:visited,

div.rightBoxContainer div.sideBoxContent{

color:#ffffff;

}





div.sideBoxContent ul li a:link, div.sideBoxContent ul li a:visited{

font-family: Arial;

font-size: 11px;

color: #ffffff;

}

div.sideBoxContent ul li a:hover{

color: #ffffff;

}

div.rightBoxContainer div.sideBoxContent{

background-color: #191919;

}

h3.rightBoxHeading, div.rightBoxContainer h3.rightBoxHeading {

font-family: Arial;

font-size: 11px;

color: #ffffff;

font-weight: bold;

text-transform:uppercase;



}

h3.rightBoxHeading a, h3.rightBoxHeading label, .rightBoxHeading a:visited{

font-family: Arial;

font-size: 11px;

color: #ffffff;

font-weight: bold;

text-transform:uppercase;}

#manufacturersHeading, #currenciesHeading, #musicgenresHeading, #recordcompaniesHeading, #searchHeading, #search-headerHeading {

font-size: 0.9em;

color: #000000;

}



.rightBoxHeading {

background-color: #191919;

margin: 0px;





padding-bottom:7px;

padding-top:6px;





}

.leftBoxHeading{

margin: 0px;

background-color: #191919;

padding-bottom:7px;

padding-top:6px;



}

.centerBoxHeading{

margin: 0px 0px 0px 0px;

background-color: #191919;

/* background-image: url(../images/bg_title.gif); */

padding: 10px 20px 10px 0px;

}

.leftBoxContainer, .rightBoxContainer {



margin: 0px;

/*

border: 1px solid #9a9a9a;

border-bottom: 5px solid #336633;

*/

margin-top: 1.5em;



}



.sideBoxContent {

padding: 10px;



}



h3.leftBoxHeading a:hover, h3.rightBoxHeading a:hover {

color: #c4661b;

text-decoration: none;

}



.leftBoxHeading a:visited, .centerBoxHeading a:visited {

color: #ffffff;



}



.centeredContent, TH, #cartEmptyText, #cartBoxGVButton, #cartBoxEmpty, #cartBoxVoucherBalance, #navCatTabsWrapper, #navEZPageNextPrev, #bannerOne, #bannerTwo, #bannerThree, #bannerFour, #bannerFive, #bannerSix, #siteinfoLegal, #siteinfoCredits, #siteinfoStatus, #siteinfoIP, .center, .cartRemoveItemDisplay, .cartQuantityUpdate, .cartQuantity, .cartTotalsDisplay, #cartBoxGVBalance, .leftBoxHeading, .centerBoxHeading,.rightBoxHeading, .productListing-data, .accountQuantityDisplay, .ratingRow, LABEL#textAreaReviews, #productMainImage, #reviewsInfoDefaultProductImage, #productReviewsDefaultProductImage, #reviewWriteMainImage, .centerBoxContents, .specialsListBoxContents, .categoryListBoxContents, .additionalImages, .centerBoxContentsSpecials, .centerBoxContentsAlsoPurch, .centerBoxContentsFeatured, .centerBoxContentsNew, .gvBal, .attribImg {



text-align:center;

padding: 0.1em;


}



#bestsellers .wrapper {

margin: 0em 0em 0em 1.5em;

}



#bestsellers ol {

padding: 0;

margin-left: 1.1em;

}



#bestsellers li {

padding: 0;

margin: 0.3em 0em 0.3em 0em;

}

/*



#bannerboxHeading {

background-color: #0000CC;

}



*/

#upProductsHeading {

text-align: left;

}



#upDateHeading {

text-align: right;

}



/* categories box parent and child categories */

A.category-top, A.category-top:visited {

color: #ffffff;

font-family: arial;

font-size: 11px;

text-decoration: none;



}

A.category-top:hover{

color:#CCCCCC;

}

A.category-links, A.category-links:visited {

color: #ffffff;

font-family: arial;

font-size: 11px;

text-decoration: none;

}

A.category-links, A.category-links:hover {

color:#ffffff;

}

A.category-subs, A.category-products, A.category-subs:visited, A.category-products:visited {

color: #ffffff;

text-decoration: none;

}

A.category-subs:hover, A.category-products:hover {

color:#ffffff;

}

SPAN.category-subs-parent {

font-weight: bold;

}

SPAN.category-subs-selected {

font-weight: bold;

}

/* end categories box links */



/*misc*/

.back {

float: left;

}



.forward {

float: right;

}



.bold {

font-weight: bold;

}



.rowOdd {

background-color: #E8E8E8;

height: 1.5em;

vertical-align: top;

}



.rowEven {

background-color: #E7E7E7;

height: 1.5em;

vertical-align: top;

}



CAPTION {

/*display: none;*/

}



#myAccountGen li, #myAccountNotify li {

margin: 0;

}



.accountTotalDisplay, .accountTaxDisplay {

width: 20%;

text-align: right;

/*vertical-align: top*/

}



.accountQuantityDisplay {

width: 10%;

vertical-align: top

}



TR.tableHeading {

background-color: #cacaca;

height: 2em;

}



.productListing-rowheading {

background-color: #000000;

background-image: url(../images/tile_back.gif);

height: 2em;

color: #000000;

}



#siteMapList {

width: 90%;

float: right;

}



.ratingRow {

margin: 1em 0em 1.5em 0em;

}



LABEL#textAreaReviews {

font-weight: normal;

margin: 1em 0em;

}



#popupShippingEstimator, #popupSearchHelp, #popupAdditionalImage, #popupImage, #popupCVVHelp, #popupCouponHelp, #popupAtrribsQuantityPricesHelp, #infoShoppingCart {

background-color: #000000;

}

.select {

width: 143px;

color: #000000;

font-family: Tahoma;

font-size: 11px;

}

.input {

font-family: Tahoma;

font-size: 11px;

color: #333333;

width:500px;

font-weight: normal;



}





.txt_title {

font-family: Arial;

font-size: 11px;

color: #333333;

text-transform: uppercase;

font-weight: bold;

}

.txt_price_bold {

font-family: Arial;

font-size: 11px;

font-weight: bold;

text-transform: uppercase;

color: #CC0000;

}

.txt_price01 {

font-family: Arial;

font-size: 14px;

font-weight: bold;

color: #333333;

}







.input02 {

font-family: Arial;

font-size: 11px;

color: #000000;

width: 200px;

}

.input03 {

font-family: Arial;

font-size: 11px;

color: #000000;

width: 95px;

}

.content {

font-family: arial;

font-size: 11px;

color: #ffffff;

}



.txt_content03 {

font-family: Arial;

font-size: 11px;

color: #333333;

}





.txt_content03_bold {

font-family: Arial;

font-size: 11px;

color: #333333;

font-weight: bold;

}

div.txt_content a, div.txt_content a:link{

font-family: Arial;

font-size: 11px;

color: #ffffff;

}

.txt_content {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 10px;

font-weight: bold;

color: #ffffff;

}

.txt_content a:link, .txt_content a:visited {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 10px;

font-weight: bold;

color: #ffffff;

}

.txt_content a:hover {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 10px;

font-weight: bold;

color: #ffcb4d;

}

div.txt_content a:hover{

color:#8B8C87;

}

.txt_content01_bold {

font-family: Arial;

font-size: 11px;

color: #ffffff;

font-weight: bold;

}

.txt_content_bold {

font-family: Arial;

font-size: 11px;

font-weight:bold;

color: #990000;

}





.txt_content02 {

font-family: Arial;

font-size: 11px;

color: #CC0000;

}

.txt_content02_bold {

font-family: Arial;

font-size: 11px;

font-weight: bold;

color: #FF9900;

}

div.wrapper ol li a, div.wrapper{

font-family: Arial;

font-size: 11px;

color: #ffffff;

}

div.wrapper ol li a:hover{

color:#ffffff;

}



.txt_content {

font-family: arial;

font-size: 11px;

color: #ffffff;

}

a.topNav:link, a.topNav:visited {

font-family: Arial;

font-size: 11px;

color: #ffffff;



}

a.topNav:hover{

color:#000000;

}

.bg_title {

background-color: #ffffff;

height: 28px;

width: 183px;

}

.bg_addtocart {

background-image: url(../images/bg_addtocart.gif);

height: 28px;

width: 114px;

}

.bg_top {

background-image: url(../images/bg_top.gif);

height: 49px;

}

.bg_price {

background-image: url(../images/bg_price.gif);

height: 28px;

width: 248px;

}

.bg_side {

background-color: #FFFFFF

width: 206px;

}

.bg_sidebar {

background-image: url(../images/bg_blue.gif);

height: 39px;

}



a.txt_content01 {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 10px;

font-weight: normal;

color: #ffffff;

}a.txt_content01:hover {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 10px;

font-weight: normal;

color: #ffffff;



text-decoration: none;

}

.txt_content01 {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 10px;

font-weight: normal;

color: #ffffff;

}

.txt_content02 {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 11px;

font-weight: bold;

color: #ffffff;

}

.txt_content06 {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 11px;

font-weight:normal;

color: #ffffff;

}

.txt_content06 a:link,.txt_content06 a:visited {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 11px;

font-weight:normal;

color: #E4EAA8;

}

.txt_content06 a:hover {

font-family: Tahoma, Arial, "Times New Roman";

font-size: 11px;

font-weight:normal;

color: #CCCCCC;

/* text-decoration: underline; */

}