Customized popup or alert box using CSS3, HTML5 and jQuery

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<script type="text/javascript" src="http://code.jquery.com/jquery-1.6.4.min.js"></script>

<a href="#login-box" class="login-window">Login / Sign In</a>
<div id="login-box" class="login-popup"> <a href="#" class="close"><img src="close.png" width="32" height="32" style="float:right" class="btn_close" title="Close Window" alt="Close" /></a>
  <form method="post" class="signin" action="#">
    <fieldset class="textbox">
      <label class="username"> <span>Username or email</span>
        <input id="username" name="username" value="" type="text" autocomplete="on" placeholder="Username">
      </label>
      <label class="password"> <span>Password</span>
        <input id="password" name="password" value="" type="password" placeholder="Password">
      </label>
      <button class="submit button" type="button">Sign in</button>
      <p> <a class="forgot" href="#">Forgot your password?</a> </p>
    </fieldset>
  </form>
</div>


<style>
#mask {
    display: none;
    background: #000;
    position: fixed; left: 0; top: 0;
    z-index: 10;
    width: 100%; height: 100%;
    opacity: 0.8;
    z-index: 999;
}

/* You can customize to your needs  */
.login-popup{
    display:none;
    background: #333;
    padding: 10px;    
    border: 2px solid #ddd;
    float: left;
    font-size: 1.2em;
    position: fixed;
    top: 50%; left: 50%;
    z-index: 99999;
    box-shadow: 0px 0px 20px #999; /* CSS3 */
        -moz-box-shadow: 0px 0px 20px #999; /* Firefox */
        -webkit-box-shadow: 0px 0px 20px #999; /* Safari, Chrome */
    border-radius:3px 3px 3px 3px;
        -moz-border-radius: 3px; /* Firefox */
        -webkit-border-radius: 3px; /* Safari, Chrome */
}

img.btn_close { Position the close button
    float: right;
    margin: -28px -28px 0 0;
}

fieldset {
    border:none;
}

form.signin .textbox label {
    display:block;
    padding-bottom:7px;
}

form.signin .textbox span {
    display:block;
}

form.signin p, form.signin span {
    color:#999;
    font-size:11px;
    line-height:18px;
}

form.signin .textbox input {
    background:#666666;
    border-bottom:1px solid #333;
    border-left:1px solid #000;
    border-right:1px solid #333;
    border-top:1px solid #000;
    color:#fff;
        border-radius: 3px 3px 3px 3px;
    -moz-border-radius: 3px;
        -webkit-border-radius: 3px;
    font:13px Arial, Helvetica, sans-serif;
    padding:6px 6px 4px;
    width:200px;
}

form.signin input:-moz-placeholder { color:#bbb; text-shadow:0 0 2px #000; }
form.signin input::-webkit-input-placeholder { color:#bbb; text-shadow:0 0 2px #000;  }

.button {
    background: -moz-linear-gradient(center top, #f3f3f3, #dddddd);
    background: -webkit-gradient(linear, left top, left bottom, from(#f3f3f3), to(#dddddd));
    background:  -o-linear-gradient(top, #f3f3f3, #dddddd);
        filter: progid:DXImageTransform.Microsoft.gradient(startColorStr='#f3f3f3', EndColorStr='#dddddd');
    border-color:#000;
    border-width:1px;
        border-radius:4px 4px 4px 4px;
    -moz-border-radius: 4px;
        -webkit-border-radius: 4px;
    color:#333;
    cursor:pointer;
    display:inline-block;
    padding:6px 6px 4px;
    margin-top:10px;
    font:12px;
    width:214px;
}
.button:hover { background:#ddd; }
</style>

<script>
    $(document).ready(function() {
    $('a.login-window').click(function() {
                //Getting the variable's value from a link
        var loginBox = $(this).attr('href');
        //Fade in the Popup
        $(loginBox).fadeIn(300);
        //Set the center alignment padding + border see css style
        var popMargTop = ($(loginBox).height() + 24) / 2;
        var popMargLeft = ($(loginBox).width() + 24) / 2;
        $(loginBox).css({
            'margin-top' : -popMargTop,
            'margin-left' : -popMargLeft
        });
        // Add the mask to body
        $('body').append('<div id="mask"></div>');
        $('#mask').fadeIn(300);
        return false;
    });
    // When clicking on the button close or the mask layer the popup closed
    $('a.close, #mask').click( function() {
      $('#mask , .login-popup').fadeOut(300 , function() {
        $('#mask').remove(); 
    });
    return false;
    });
});
</script>




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