Merhaba arkadaslar menü kodlarım şu şekildedir html de fotograflar sekmesinin üzerine geldiğimde video butonunun açılmasını istiyorum açılır kapanır menüyü nasıl yaparım ?
</div>
<nav>
<ul>
<li class="current"><a href="index.html">Ana Sayfa</a></li>
<li><a href="hakkimizda.html">Hakkımızda</a></li>
<li><a href="hayvanlarimiz.html">Hayvanlarımız</a></li>
<li><a href="galeri.html">Fotoğraflar</a></li>
<li><a href="iletisim.html">iletişim</a></li>
</ul>
</nav>
<p> </p>
<p> </p>
</div>
</header>css kodlarım
/*
*/
/* ---------------------Reset----------------------- */
a,abbr,acronym,address,applet,article,aside,audio,b,blockquote,big,body,center,canvas,caption,cite,code,command,datalist,dd,del,details,dfn,dl,div,dt,em,embed,fieldset,figcaption,figure,font,footer,form,h1,h2,h3,h4,h5,h6,header,hgroup,html,i,iframe,img,ins,kbd,keygen,label,legend,li,meter,nav,object,ol,output,p,pre,progress,q,s,samp,section,small,span,source,strike,strong,sub,sup,table,tbody,tfoot,thead,th,tr,tdvideo,tt,u,ul,var{
background:transparent;
border:0 none;
font-size:100%;
margin:0;
padding:0;
border:0;
outline:0;
vertical-align:top;
color: #000;
}ol, ul {list-style:none;}blockquote, q {quotes:none;}table, table td {
padding:0;
border:none;
border-collapse:collapse;
color: #333;
}img {vertical-align:top;}embed {vertical-align:top;}
article, aside, audio, canvas, command, datalist, details, embed, figcaption, figure, footer, header, hgroup, keygen, meter, nav, output, progress, section, source, video {display:block;}
mark, rp, rt, ruby, summary, time {display:inline;}
input, textarea {border:0; padding:0; margin:0; outline: 0;}
iframe {border:0; margin:0; padding:0;}
input, textarea, select {margin:0; padding:0px;}
/* -------------------------------------------- */
/* ------------------Style---------------------- */
/* -------------------------------------------- */
html, body {width:100%; padding:0; margin:0;}
body {background: #C0504D url(../images/pattern22.png) ;color: #474747;font: 12px/25px Arial, Helvetica, sans-serif;}
/*-------------------------*/
a{color: #474747;text-decoration: none;}
a:hover {color: #C0504D; text-decoration: none;}
a.button, input.button { cursor: pointer; color: #ffffff; line-height: 14px; font-family: Arial, Helvetica, sans-serif; font-size: 14px; font-weight: bold; background: #C0504D; border:1px solid #ffffff; -webkit-border-radius: 4px;-moz-border-radius: 4px;-khtml-border-radius: 4px;border-radius: 4px;;}
a.button { display: inline-block; text-decoration: none; padding: 6px 12px 6px 12px;}
input.button { margin: 0; border: 0; height: 24px; padding: 0px 12px 0px 12px;}
a.button:hover, input.button:hover {}
.clearboth{ clear:both;}
/*--------------------*/
/*-------------Grid */
.zerogrid{ width: 960px; position: relative; margin: 0 auto; padding: 0;}
.zerogrid .row{}
.zerogrid .col-1-3{float: left; display: inline; margin:10px;}
.zerogrid .col-1-3{width:31%;}
.zerogrid .col-right,.zerogrid .col-left{float: left; display: inline; margin:20px;}
.zerogrid .col-right{width:280px;}
.zerogrid .col-left{width:600px;}
.zerogrid:after { content: "\0020"; display: block; height: 0; clear: both; visibility: hidden; }
.zerogrid .row:before,.row:after { content: '\0020'; display: block; overflow: hidden; visibility: hidden; width: 0; height: 0; }
.zerogrid .row:after{clear: both; }
.zerogrid .row{zoom: 1;}
/*--------------------*/
/*-------------header */
header {}
.wrap-header{width:960px;height: 130px; position:relative; margin: 0px auto; background:#ffffff; margin-top:50px; border-bottom:1px dashed #999999;}
.wrap-header #logo {
position:absolute;
top:-1px;
left: -1px;
width: 100%;
height: 131px;
}
.pagetop{background:#FFF; height:40px; margin-top:3px;}
.wrap-pagetop{width:960px; position:relative;margin:0 auto; }
.wrap-pagetop #search {position: absolute;top: 7px;right: 10px; width: 208px;z-index: 15;}
.wrap-pagetop .button-search { position: absolute; left: 0px; background: url('../images/button-search.png') center center no-repeat; width: 28px; height: 24px; border-right: 1px solid #CCCCCC; cursor: pointer;}
.wrap-pagetop #search input { background: #FFF; padding: 1px 1px 1px 33px; width: 172px; height: 21px; border: 1px solid #CCCCCC; -webkit-border-radius: 3px; -moz-border-radius: 3px; -khtml-border-radius: 3px; border-radius: 3px;}
.wrap-pagetop .shareicons{position: absolute;top: 5px;left: 5px;}
.wrap-pagetop .shareicons ul{list-style: none;margin: 0;padding: 0;}
.wrap-pagetop .shareicons ul li{position: relative;float: left;}
/*------------navigation and pagination */
nav {position:absolute; top:50px; right:20px; height: 37px;}
nav ul {list-style: none;margin: 0;padding: 0;}
nav ul li {position: relative;float: left;padding: 7px 5px 0px 5px; margin:0 10px 10px 0; background:#F0F0F0;-webkit-border-radius: 5px; -moz-border-radius: 5px; -khtml-border-radius: 5px; border-radius: 5px;}
nav ul li:hover, nav ul li.current{background-color:#C0504D;}
nav ul li:hover a, nav ul li.current a{color:#ffffff;}
nav ul li a {font-size: 14px; line-height:14px;color:#999999;display: block;padding: 6px 10px;margin-bottom: 5px;z-index: 6;position: relative; text-transform:uppercase;}
nav ul li:hover a{color:#ffffff;}
#pagi{clear: both; margin: 30px auto;padding: 0;list-style: none;width: 180px;}
#pagi li {float: left;margin-right: 10px;}
#pagi li a {display: block; text-decoration: none; color: #717171;font: bold 11px Arial, sans-serif;padding: 5px 8px;
-webkit-border-radius: 3px; -moz-border-radius: 3px; border-radius: 3px; background: #ffffff;}
#pagi li a.current, #pagi li a:hover {color: #ffffff; background: #C0504D;}
/*-------------content */
#content {width:960px; margin:0 auto; background-color:#FFF;}
.feature{margin-bottom:20px;}
.welcome{
margin: 0px 20px 20px 20px;
padding: 30px;
font-size:20px;
text-align:center;
background-color: #B6D894;
}
.block01{ text-align:center; padding-bottom:20px;}
.block01 article{width:250px; margin:0 auto; background:#EEEEEE; border-bottom:2px solid #999;}
.block01 img{-webkit-filter: grayscale(100%);}
.block01 a img {-webkit-transition: all 0.5s;}
.block01 a img:hover {
-webkit-filter: none;
word-spacing: 2px;
}
.block01 a img.brightness:hover {-webkit-filter: brightness(0);}
.block01 h2{ font-size:14px; padding:10px 0px;}
#main-content{}
#main-content article{ clear: both; font-size:14px; margin:10px 0px;}
#main-content article .heading{}
#main-content article h2{font-size:18px; line-height:25px; text-transform:uppercase;}
#main-content article .info{}
#main-content article img{float:left; padding:5px; border:1px solid #999; display:inline-block;}
#main-content article p{margin-bottom:10px; display:inline-block;}
#main-content article .more{float:right;}
#main-content .comment{font-weight:bold; margin:50px 0px; width:100%;}
#main-content .comment div{margin-bottom: 20px; vertical-align:middle; }
#main-content .comment input{border: 2px solid #999999;padding: 8px 10px;width:250px;}
#main-content .comment textarea{border: 2px solid #999999;padding: 8px 10px;width:100%;}
#main-content .comment input[type="submit"] {cursor: pointer; width:100px; float:right;
background: -webkit-linear-gradient(top, #efefef, #ddd);background: -moz-linear-gradient(top, #efefef, #ddd);
background: -ms-linear-gradient(top, #efefef, #ddd);background: -o-linear-gradient(top, #efefef, #ddd);
background: linear-gradient(top, #efefef, #ddd);
color: #333;text-shadow: 0px 1px 1px rgba(255,255,255,1); border: 2px solid #999999;}
#main-content .comment input[type="submit"]:hover {
background: -webkit-linear-gradient(top, #eee, #ccc); background: -moz-linear-gradient(top, #eee, #ccc);
background: -ms-linear-gradient(top, #eee, #ccc); background: -o-linear-gradient(top, #eee, #ccc);
background: linear-gradient(top, #eee, #ccc); border: 2px solid #bbb;}
#main-content .comment input[type="submit"]:active {
background: -webkit-linear-gradient(top, #ddd, #aaa); background: -moz-linear-gradient(top, #ddd, #aaa);
background: -ms-linear-gradient(top, #ddd, #aaa); background: -o-linear-gradient(top, #ddd, #aaa);
background: linear-gradient(top, #ddd, #aaa); border: 2px solid #999;}
#sidebar{}
#sidebar section{margin-bottom:20px;}
#sidebar .heading{ padding:5px; background:#C0504D;-webkit-border-radius: 5px; -moz-border-radius: 5px; -khtml-border-radius: 5px; border-radius: 5px;}
#sidebar .heading h2{font-size:22px; font-weight:normal; display:inline; padding:0 10px; color:#ffffff;}
#sidebar .content{padding:15px}
#sidebar .content ul{ font-size:14px; list-style-type:circle; margin-left:20px;}
#sidebar .content ul li{border-bottom: 1px solid #E1E1E1; padding:5px;}
#sidebar .content .post {margin-bottom: 20px;}
#sidebar .content .post h4{ font-size:14px; font-weight:normal;}
#sidebar .content .post img{ float:left; padding:5px; border:1px solid #CCC; margin-right:10px;}
#sidebar .content .post p{color:#A3A3A3; font-style:italic;}
/*------------footer */
.block02{width:960px; margin:0px auto 50px auto; padding:10px 0px; background-color:#F0F0F0; border-top:1px dashed #999999;}
footer {}
footer section{margin-bottom:20px;}
footer .heading{ padding:5px; border-bottom:3px double #999999;}
footer .heading h2{
font-size:22px;
font-weight:normal;
display:inline;
padding:0 10px;
color: #333;
}
footer .content{padding:15px}
footer .content a{}
footer .content ul{ font-size:14px; list-style-type:circle; margin-left:20px;}
footer .content ul li{border-bottom: 1px solid #E1E1E1; padding:5px;}
footer .content .post {margin-bottom: 20px;}
footer .content .post h4{ font-size:14px; font-weight:normal;}
footer .content .post img{ float:left; padding:5px; border:1px solid #CCC; margin-right:10px;}
footer .content .post p{color:#A3A3A3; font-style:italic;}
footer .copyright{text-align:center; background:#333333; height:30px; padding-top:10px; color:#8C9999;}
footer .copyright a{color:#8C9999; text-decoration:underline;}
footer .copyright a:hover{color:#CCCCCC; text-decoration:none;}
/*------------gallery*/ 
