메인 가운데 정렬이요...

저기 사진처럼 파란색 안에있는 메인을( 화면 왼쪽에 붙어있어 왼쪽 여백이없음...) 중앙으로 (왼쪾 오른쪽 여백 있게) 만들려고 하는데 css 잘 알지 못해서 이렇게 올립니다^^




css 입니다





@import url("./default.css");

/* Layout */
body { font-size:9pt; color: #787878; font-family:"돋음" ; text-decoration: none; line-height:155%;}
#Header {width:100%; padding:0; text-align:left;}
#Container {margin:0 auto; width:2048px; padding:15px 0 0 0; overflow:hidden; }
.position_l {float:left; width:240px;}
.position_m {float:left; width:728px; margin:0 20px 0 20px; _margin:0 8px 0 16px;}
.position_r {float:left; width:240px;}
.content {float:left; margin:0 0 0 20px; width:730px;}
#Footer {width:2040px; margin:0 auto; padding:0; overflow:hidden;}


.top {width:2048px; margin:40px auto 18px ; overflow:hidden;}
.top h1 {float:left; margin:0 18px 0 12px;}
.search {float:left; vertical-align:middle; margin:7px 18px 0 0;}
.search input {vertical-align:middle;}
.search input.w100 {width:100px; height:18px; background:#ffffff; border:1px solid #d6d6d6; padding:0 0 0 3px; margin:0 2px 0 0;}

.tm {float:left; margin:8px 0 0 0;}
.tm li {display:inline; border-right:1px solid #d6d6d6; margin:0 4px 0 0; padding:0 8px 0 0; .padding:0 6px 0 0; .margin:0 8px 0 0; letter-spacing: -1pt;}
.tm li.lst {border:none;}


.tmenu_bg{margin:0 auto 5px; width:100%; background:#121212; padding:5px 0 5px 0; height:28px;}
.tmenu {margin:0 auto; width:2048px;}
.tmenu ul {}
.tmenu li {float:left; color:#e6e6e6; letter-spacing:-0.5pt; font-weight:bold; margin:5px 15px 5px 15px; position:relative;}
.tmenu li em {color:#ffffff;}
.tmenu li em.ov {background:#6EAA0F; padding:3px 5px 3px 5px;}
.tmenu li li{color:#313131; display:inline;}
.tmenu li div {position:absolute; top:32px; left:-15px; z-index:10; width:900px; display:none;}
.tmenu_s_bg {width:100%; border-bottom:1px dashed #d6d6d6; overflow:hidden; height:30px;}



.outlogin_in {border:1px solid #d6d6d6; background:#F4F4F4; position:relative; font-size:8pt;}
.outlogin_in h2 {margin:15px 0 10px 20px; .margin:15px 0 7px 20px;}
.outlogin_in span {display:block; margin:0 0 5px 20px;}
.outlogin_in span.btns {position:absolute; top:42px; right:18px;}
.outlogin_in input.w100 {width:110px; background:#ffffff; border:1px solid #d6d6d6; padding:2px 0 2px 3px; letter-spacing: -0.5pt; font-size:9pt;}
.outlogin_in p {text-align:center; margin:12px 0 12px 0; font-size:8pt; font-family:"dotum";}

.outlogin_out {border:1px solid #d6d6d6; background:#F4F4F4; position:relative;}
.outlogin_out h2 {margin:15px 0 10px 20px; vertical-align:bottom;}
.outlogin_out span.adm {position:absolute; top:16px; left:92px;}
.outlogin_out span.mbtt{display:block; margin:5px 0 0 20px;}
.outlogin_out span.btns {position:absolute; top:32px; right:18px;}
.outlogin_out ul{margin:10px 0 0 0; height:32px; border-top:1px solid #d6d6d6; padding:5px 0 5px 0;}
.outlogin_out li{float:left; height:32px; line-height:32px; margin:0 11px 0 11px; _margin:0 9px 0 9px;}
.outlogin_out li a {display:inline-block; width:31px; height:32px;}
.outlogin_out li a em {display:block; text-indent:-5000px; font-size:0;}
.outlogin_out li.myscrap {background:url(../images/member/ic_scrap.gif) 0 0 no-repeat; width:31px; height:32px;}
.outlogin_out li.mypoint{background:url(../images/member/ic_point.gif) 0 0 no-repeat; width:31px; height:32px;}
.outlogin_out li.mymemo {background:url(../images/member/ic_memo.gif) 0 0 no-repeat; width:31px; height:32px;}
.outlogin_out li.myinfo{background:url(../images/member/ic_modify.gif) 0 0 no-repeat; width:31px; height:32px;}


.la_basic {margin:7px 0 0 0; border:1px solid #d6d6d6;}
.la_basic h3{color:#313131; margin:7px 0 5px 10px;}
.la_basic ul{margin:0 10px 10px 10px;}
.la_basic li{margin:2px 0 2px 0; letter-spacing: -0.5pt;}

.la_basic2 {margin:7px 0 0 0; border:1px solid #d6d6d6;}
.la_basic2 h3{color:#313131; border-bottom:1px solid #d6d6d6; padding:5px 0 5px 10px;}
.la_basic2 ul{margin:7px 5px 10px 5px;}
.la_basic2 li{margin:2px 0 2px 5px; letter-spacing:0;}

.la_basic3 {margin:7px 0 0 0; border:1px solid #d6d6d6;}
.la_basic3 h3{color:#313131; border-bottom:1px solid #d6d6d6; padding:5px 0 5px 10px;}
.la_basic3 ul{margin:7px 5px 10px 5px; _margin:7px 3px 0 5px;}
.la_basic3 li{margin:6px 0 6px 5px; letter-spacing: -0.5pt; line-height:140%; _margin:0 0 0 5px;}
.la_basic3 span {display:block; color:#808080; font-size:8pt; letter-spacing:0; }

.la_basic4 {color:#313131; margin:10px 0 5px 0; border:1px solid #d6d6d6; background:#F4F4F4; position:relative;}
.la_basic4 h3{margin:15px 0 10px 17px; color:#373737;}
.la_basic4 p {position:absolute; top:18px; right:0; background:url(../images/common/more.png) 0 0 no-repeat; padding:0 0 0 20px; width:30px; height:10px;}
.la_basic4 ul{margin:0 0 15px 13px;}
.la_basic4 li{margin:6px 0 2px 5px; color:#505050; letter-spacing: -0.5pt; line-height:140%;}
.la_basic4 span {display:block; color:#808080; font-size:8pt; letter-spacing:0;}


.la_menu {border:1px solid #d6d6d6; background:#F4F4F4; margin:10px 0 0 0;}
.la_menu h3{background:url(../images/common/h3.gif) 10px 3px no-repeat; padding:0 0 7px 24px; margin:10px 0 0 0; border-bottom:1px solid #d6d6d6; color:#121212;}
.la_menu ul {margin:10px 0 10px 0;}
.la_menu li {margin:5px 0 5px 12px; color:#505050; letter-spacing: -0.5pt; line-height:145%;}
.la_menu a:hover {color:#121212; font-weight:bold;}


.visit {margin:7px 0 0 0; border:1px solid #d6d6d6; padding:7px 10px 7px 10px; }
.visit ul {}
.visit li {background:url(../images/common/dot.gif) 0 3px no-repeat; padding:0 0 0 12px; margin:2px 0 2px 0; letter-spacing:-0.5pt; line-height:145%;}
.visit li em {font-weight:bold;}


.st {border:5px solid #747474; padding:15px 15px 15px 18px; background:url(../images/common/st_bg.gif) right 50% no-repeat;}
.st h4 {margin:0 0 7px 0;}
.st span {font-size:9pt; letter-spacing:-0.5pt; line-height:140%;}

.navi {margin:15px 0 0 5px; color:#999999;}
.navi em {font-weight:bold; color:#313131; }

.board {margin:20px 0 0 0;}

.ad_c {}

.la_news {margin:12px 0 0 0;}
.la_news h3 {font-size:12pt; font-weight:bold; color:#313131; margin:0; letter-spacing:-1pt;}
.la_news p {color:#999999; font-size:9pt; line-height:145%; margin:7px 0 0 0;}
.la_news ul {margin:7px 0 0 0;}
.la_news li {text-align:right; padding:1px 11px 1px 2px; color:#9A9A9A; letter-spacing:0pt;}
.la_news span {float:left; color:#747474; }


.la_tab {margin:17px 0 0 0;}
.tab {border-bottom:1px solid #d6d6d6; overflow:hidden; margin:0; zoom:1;}
.tab li {float:left; margin:0 3px 0 2px; background:#686868; width:100px; text-align:center; padding:4px 0 4px 0; _margin:0 2px 0 1px;}
.tab li.ov {background:#000000; color:#ffffff; font-weight:bold;}

.tab_m {clear:both; margin:8px 0 0 0;}
.tab_m ul {margin:8px 0 0 0;}
.tab_m li {text-align:right; color:#9A9A9A; margin:3px 10px 3px 0; letter-spacing:0;}
.tab_m li span {float:left; color:#787878; margin:0 0 0 2px;}


.la_psd {float:left; margin:17px 0 0 0;}
.la_psd h3 {color:#313131; background:url(../images/common/ar.gif) 0 3px no-repeat; padding:0 0 0 13px; margin:0 0 5px 0;}
.la_psd h3 em {font-weight:normal; letter-spacing:-0.5pt;}
.la_psd dl {clear:both; margin:0 0 10px 0;}
.la_psd dt {float:left;}
.la_psd dt img {border:1px solid #d6d6d6;}
.la_psd img {display:block; margin:0 7px 0 0; }
.la_psd dd {color:#787878; letter-spacing:-1pt; line-height:140%; padding:3px 7px 0 7px;}
.la_psd dd.tt {margin:0 0 5px 0;}


.la_photo {float:left; margin:17px 0 0 0; width:420px;}
.la_photo h3 {border-top:1px solid #d6d6d6; border-bottom:1px solid #d6d6d6; padding:5px 0 5px 3px;}
.la_photo ul {margin:10px 5px 0 5px;}
.la_photo li {float:left; margin:0 7px 0 7px; text-align:center;}
.la_photo span {display:block; margin:2px 0 0 0;}


.ad_r {}

.food {float:left; margin:15px 0 0 0;}
.food h3 {color:#313131; background:url(../images/common/ic.gif) 0 2px no-repeat; padding:0 0 0 18px;}
.food dl {clear:both; width:210px; margin:7px 0 7px 3px; overflow:hidden;}
.food dt {float:left; width:90px;}
.food dd {float:left; width:120px; margin:5px 0 0 0;}
.food dd.txt {font-size:9pt; letter-spacing: -1pt; color:#959595; line-height:140%;}

.site {width:220px; float:left; margin:10px 0 0 0;}
.site h3 {color:#313131; background:url(../images/common/ic.gif) 0 2px no-repeat; padding:0 0 0 18px;}
.site ul {width:220px; margin:0 0 10px 0;}
.site li {float:left; margin:5px 3px 5px 3px; font-size:9pt; letter-spacing: -1pt; text-align:center;}
.site li img {display:block; margin:0 0 3px 0;}

.event {margin:10px 0 0 0;}
.event span {display:block; margin:0 0 5px 0;}


.search_box {border:1px solid #d6d6d6; background:#F6F6F6; padding:25px 0 25px 0; text-align:center; margin:10px 0 30px 0;}
.search_box select{vertical-align:middle;}
.search_box input {vertical-align:middle; font-size:9pt; font-family:"dotum"; border:1px solid #d6d6d6; height:17px; padding:1px 0 0 2px;}
.search_box em {vertical-align:middle;}
.search_box input.w200 {width:150px;}
.search_box input.bgno {background:none; border:none;}

.search_list {margin:0 10px 0 10px;}
.search_list h3{background:url(../images/common/ar_b.gif) 0 2px no-repeat; color:#000000; padding:0 0 0 14px;}
.search_list ul {margin:10px 0 25px 10px;}
.search_list li {background:url(../images/common/dot.gif) 0 1px no-repeat; padding:0 0 0 13px;}
.search_list h4 {background:url(../images/common/ar_2.gif) 0 2px no-repeat; padding:0 0 0 10px; font-weight:bold; color:#000000; margin:0 0 3px 0;}
.search_list dl{margin:0 0 20px 10px; overflow:hidden;}
.search_list dt{margin:0 0 5px 0; font-size:9pt; font-family:"dotum"; line-height:155%:}
/*.search_list span{text-decoration:underline; } */
.search_list dd{margin:0 0 2px 0; line-height:155%;}
.ttxt {color:#898989; line-height:120%; font-size:8pt; font-family:"dotum";}
.ttdate {color:#b9b9b9; font-size:8pt; font-family:"dotum";}
.tt_8_gr{font-size:8pt; font-family:"dotum"; color:#787878; font-weight:normal; letter-spacing:0pt;}
.tt_8_g {color:#276347;}
.tt_b {color:#000000; font-weight:bold;}


.bottom {border-top:1px dashed #d6d6d6; margin:13px 0 10px 0;}
.bottom h2 {margin:30px 40px 20px 40px; float:left;}
.bottom ul {margin:20px 0 10px 0; overflow:hidden;}
.bottom li {float:left; margin:0 5px 0 5px;}
.bottom span {display:inline-block; font-style:normal; font-size:8pt; font-family:"dotum"; letter-spacing:-0.5pt; margin:0 0 0 4px;}


.tt_b {color:#000000;}
.tt_r {color:#F52061;}
.tt_g {color:#6EAA0F;}
.tt_gb {color:#217655;}
.tt_r_b {color:#F52061; font-weight:bold;}
.tt_w {color:#f5f5f5;}
.ttb {font-weight:bold;}