Actually I have done the sliding login panel on page load but on page load when it slides the login btn should change to close

/***** clearfix *****/
.clear {clear: both;height: 0;line-height: 0;}
.clearfix:after {content: ".";display: block;height: 0;clear: both;visibility: hidden;}
.clearfix {display: inline-block;}
/* Hides from IE-mac \*/
* html .clearfix {height: 1%;}
.clearfix {display: block;}
/* End hide from IE-mac */
.clearfix {height: 1%;}
.clearfix {display: block;}

/* Panel Tab/button */
.tab {
background: url(../images/tab_bb.png) repeat-x 0 0;
height: 42px;
position:relative;
top: 0;
z-index: 999;
}

.tab ul.login {
display: block;
position: relative;
float: right;
clear: right;
height: 42px;
width: auto;
font-weight: bold;
line-height: 42px;
margin: 0;
right: 150px;
color: white;
font-size: 80%;
text-align: center;
}

.tab ul.login li.left {
background: url(../images/tab_rr.png) no-repeat left 0;
height: 42px;
width: 30px;
padding: 0;
margin: 0;
display: block;
float: left;
}

.tab ul.login li.right {
background: url(../images/tab_ll.png) no-repeat left 0;
height: 42px;
width: 30px;
padding: 0;
margin: 0;
display: block;
float: left;
}

.tab ul.login li {
text-align: left;
padding: 0 6px;
display: block;
float: left;
height: 42px;
background: url(../images/tab_mm.png) repeat-x 0 0;
}

.tab ul.login li a {
color: #15ADFF;
}

.tab ul.login li a:hover {
color: white;
}

.tab .sep {color:#414141}

.tab a.open, .tab a.close {
height: 20px;
line-height: 20px !important;
padding-left: 30px !important;
cursor: pointer;
display: block;
width: 100px;
position: relative;
top: 11px;
}

.tab a.open {background: url(../images/bt_open.png) no-repeat left 0;}
.tab a.close {background: url(../images/bt_close.png) no-repeat left 0;}
.tab a:hover.open {background: url(../images/bt_open.png) no-repeat left -19px;}
.tab a:hover.close {background: url(../images/bt_close.png) no-repeat left -19px;}

/* sliding panel */
#toppanel {
position: absolute; /*Panel will overlap content */
/*position: relative;*/ /*Panel will "push" the content down */
bottom: 0;
width: 100%;
z-index: 999;
text-align: center;
margin-left: auto;
margin-right: auto;
}

#panel {
width: 100%;
height: 270px;
color: #999999;
background: #272727;
overflow: hidden;
position: relative;
z-index: 3;
display: none;
}

#panel h1 {
font-size: 1.6em;
padding: 5px 0 10px;
margin: 0;
color: white;
}

#panel h2{
font-size: 1.2em;
padding: 10px 0 5px;
margin: 0;
color: white;
}

#panel p {
margin: 5px 0;
padding: 0;
}

#panel a {
text-decoration: none;
color: #15ADFF;
}

#panel a:hover {
color: white;
}

#panel a-lost-pwd {
display: block;
float: left;
}

#panel .content {
width: 960px;
margin: 0 auto;
padding-top: 15px;
text-align: left;
font-size: 0.85em;
}

#panel .content .left {
width: 280px;
float: left;
padding: 0 15px;
border-left: 1px solid #333;
}

#panel .content .right {
border-right: 1px solid #333;
}

#panel .content form {
margin: 0 0 10px 0;
}

#panel .content label {
float: left;
padding-top: 8px;
clear: both;
width: 280px;
display: block;
}

#panel .content input.field {
border: 1px #1A1A1A solid;
background: #414141;
margin-right: 5px;
margin-top: 4px;
width: 200px;
color: white;
height: 16px;
}

#panel .content input:focus.field {
background: #545454;
}

/* BUTTONS */
/* Login and Register buttons */
#panel .content input.bt_login,
#panel .content input.bt_register {
display: block;
float: left;
clear: left;
height: 24px;
text-align: center;
cursor: pointer;
border: none;
font-weight: bold;
margin: 10px 0;
}

#panel .content input.bt_login {
width: 74px;
background: transparent url(../images/bt_login.png) no-repeat 0 0;
}

#panel .content input.bt_register {
width: 94px;
color: white;
background: transparent url(../images/bt_register.png) no-repeat 0 0;
}

#panel .lost-pwd {
display: block;
float:left;
clear: right;
padding: 15px 5px 0;
font-size: 0.95em;
text-decoration: underline;
}

$(document).ready(function () {

$('div#panel').fadeIn("slow");

// Expand Panel
$("#open").click(function(){
$('div#panel').slideDown("fast");

});

// Collapse Panel
$("#close").click(function(){
$("div#panel").slideUp("fast");
});

// Switch buttons from "Log In | Register" to "Close Panel" on click
$("#toggle a").click(function () {
$("#toggle a").toggle();
});

});

Image1 should be like image2