<div class="horizontalaccordion">
<ul>
    <li>
        <h3>Heading 1</h3>
        <div>Content For Panel 1.</div>
    </li>
    <li>
        <h3>Heading 2</h3>
        <div>Content For Panel 2</div>
    </li>
</ul>
</div>

<style type="text/css">
код
</style>

.horizontalaccordion>ul {
    margin: 0;
    padding: 0;
    list-style:none;
    height: 300px;
}

.horizontalaccordion>ul>li {
    display:block;
    overflow: hidden;
    float:right;
    margin: 0;
    padding: 0;
    list-style:none;
    width:40px;
    height: 300px;
 
    /* Decorative CSS */
    background:#f0f0f0;
 
    /* CSS3 Transitions */
    transition: width 0.3s ease-in-out;
    -moz-transition: width 0.3s ease-in-out;
    -webkit-transition: width 0.3s ease-in-out;
    -o-transition: width 0.3s ease-in-out;
}
 
.horizontalaccordion>ul>li>h3 {
    display:block;
    float:left;
    margin: 0;
    padding:10px;
    height:19px;
    width:280px;
 
    /* Decorative CSS */
    border-left:#f0f0f0 1px solid;
    font-family: Arial, Helvetica, sans-serif;
    text-decoration:none;
    text-transform:uppercase;
    color: #000;
    background:#cccccc;
 
    /* CSS3 Transform Rotate & Translate */
    white-space:nowrap;
    -moz-transform: rotate(90.0deg) translate(-40px,0px);  /* FF3.5+ */
    -moz-transform-origin: 0 100%;
    -o-transform: rotate(90.0deg) translate(-40px,0px);  /* Opera 10.5 */
    -o-transform-origin: 0 100%;
    -webkit-transform: rotate(90.0deg) translate(-40px,0px);  /* Saf3.1+, Chrome */
    -webkit-transform-origin: 0 100%;
    transform: rotate(90.0deg) translate(-40px,0px);  /* Saf3.1+, Chrome */
    transform-origin: 0 100%;
    filter: progid:DXImageTransform.Microsoft.BasicImage(rotation=1.0)
            progid:DXImageTransform.Microsoft.gradient(startColorstr=#ff999999, endColorstr=#ffcccccc);  /* IE6,IE7 */
    -ms-filter: "progid:DXImageTransform.Microsoft.BasicImage(rotation=1.0)"
                "progid:DXImageTransform.Microsoft.gradient(startColorstr=#ff999999, endColorstr=#ffcccccc)"; /* IE8 */
 
    /* CSS3 Gradient Effect */
    background: -moz-linear-gradient( top, #999999, #cccccc);
    background: -webkit-gradient(linear, left top, left bottom, from(#999999), to(#cccccc));
}
 
.horizontalaccordion>ul>li>div {
    display:none;
    float:left;
    overflow: auto;
    position:relative;
    top:-40px;
    left:40px;
    *top:0px;       /* IE7 Hack */
    *left:0px;      /* IE7 Hack */
    margin:0;
    width:120px;
    height:280px;
    padding:10px;
}
 
.horizontalaccordion>ul>li:hover {
    overflow: hidden;
    width: 180px;
}
 
.horizontalaccordion:hover>ul>li:hover>div {
    display:block;
}
 
.horizontalaccordion:hover>ul>li:hover>h3 {
    /* Decorative CSS */
    color:#fff;
    background:#000000;
 
    /* CSS3 Gradient Effect */
    background: -moz-linear-gradient( top, #454545, #000000); /* FF, Flock */
    background: -webkit-gradient(linear, left top, left bottom, from(#454545), to(#000000)); /* Safari, Chrome */
    filter: progid:DXImageTransform.Microsoft.BasicImage(rotation=1.0)
            progid:DXImageTransform.Microsoft.gradient(startColorstr=#ff454545, endColorstr=#ff000000); /* IE 5.5 - IE 7 */
    -ms-filter: "progid:DXImageTransform.Microsoft.BasicImage(rotation=1.0)"
                "progid:DXImageTransform.Microsoft.gradient(startColorstr=#ff454545, endColorstr=#ff000000)";   /* IE 8 */
}
 
.horizontalaccordion>ul>li>h3:hover {
    cursor:pointer;
}