http://www.benmarshall.me/traffic-pop-jquery-plugin/

118-2.css

#overlay {
  display: block;
  position: fixed;
  z-index: 999;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, .5);
}

#pop {
  display: block;
  position: fixed;
  z-index: 9999;
  width: 50%;
  min-width: 300px;
  height: auto;
  border: .5em solid rgba(0, 0, 0, .6);
  border-radius: .5em;
  background: #fff;
  font-family:Helvetica,Arial,'DejaVu Sans','Liberation Sans',Freesans,sans-serif;
  font-size: 1em;
  text-align: left;
}

#pop .title {
  margin: 0;
  padding: 10px;
  font-weight: normal;
  font-size: 1.2em;
  color: #333;
}

#pop .mid {
  background: #e8f2fc;
  border-top: .1em solid;
  border-bottom: .1em solid;
  border-color: #c7ddf8;
  padding: .8em;
  margin-bottom: .8em
}

#pop .bot {
  padding: 0 .8em .8em .8em;
  text-align: right;
  font-size: .8em;
  color: #666;
}

#pop .close {
  display: block;
  float: right;
  width: 1.6em;
  height: 1.6em;
  padding: .2em .1em 0 .1em;
  line-height: 1.6em;
  border-radius: 1.6em;
  text-align: center;
  text-shadow: .1em .1em .1em #fff;
  font-family: 'Courier New',Courier,'Nimbus Mono L',monospace;
  font-size: .6em;
  color: #666;
  text-decoration: none;
  background: #e5e5e5;
  border: .1em solid #ccc;
  box-shadow: inset .1em .1em .5em #fff;
}

#pop .close:hover {
  box-shadow: inset -.1em -.1em .5em #fff;
}