javascript - how to center div on a fullpage.js slide? -

i'm using fullpage.js plugin taken here http://alvarotrigo.com/fullpage/#secondpage . there possibility create vertical slides , i'm doing so, however, when use following html code:

<div class="section" id="section2">         <div class="slide" id="slide1">         <div id="logocontainer">             <div class="help1">                  <div id="about_img">                     london<br>                     paris<br>                     tokyo<br>                 </div>                  <div id="about_txt">                     <h2>london</h2>                     <p>                     london capital city of england. populous city in united kingdom,                     metropolitan area of on 13 million inhabitants.                     </p>                     <p>                     standing on river thames, london has been major settlement 2 millennia,                     history going founding romans, named londinium.                     </p>                 </div>              </div>         </div>     </div>         <div class="slide" id="slide2">          <!--    <img src="img/r1.png" alt="a" id="stand-one" /> -->         </div>          <div class="slide" id="slide3">             <h1>slide 3</h1>         <!--    <img src="img/r1.png" alt="a" id="stand-one" /> -->         </div>     </div> 

and css code:

.help1  #about_img{     line-height:30px;     height:660px;     width:400px;     float:left;      background-color: #eeffaa; } .help1 #about_txt{     height:660px;     width:500px;     float:left;       }     #logocontainer{        position: absolute;        top: 20%;        margin-top: -35px;/* half of #content height*/        left: 0;        width: 100%;     }     .help1 {          margin:0;        height: 660px;        width: 900px;        background-color: #b0c4de;     } 

my content of div @ left site of slide1 (thanks margin: 0;). center div inside slide, when change

.help1 {              margin:0;            height: 660px;            width: 900px;            background-color: #b0c4de;         } 

to

.help1 {              margin-left:auto;            margin-right: auto;            height: 660px;            width: 900px;            background-color: #b0c4de;         } 

then div centered, not on slide1, between slides - since have 3 of them now, div in middle of second slide. center div on slide1 , center 2 other divs on 2 other slides - possible?

use relative position slide:

.fp-slide{     position:relative; }