body{background: url(http://jcarlson.is-programmer.com/user_files/JCarlson/Image/KH.jpg) no-repeat fixed center 0} 
body{background-size:100% 100%}

.contener   
{   
  width: 300px;   
  height: 60px;   
  background-color: #00bcd4;   
  line-height: 60px;   
  color: #ffffff;   
  font-weight: 300;   
  font-family: 'Roboto';   
  font-size: 25px;   
  position: relative;   
  overflow: hidden;   
  cursor: pointer;   
  box-shadow:1px 1px 1px #333333;   
}   
.txt_button   
{   
  position: absolute;   
  width: 100%;   
}   
.contener:hover .circle  
{   
  -webkit-animation:oblik 0.4s ease-in;   
  -webkit-transform-origin: 50% 50%;   
  -moz-animation:oblik 0.4s ease-in;   
  -moz-transform-origin: 50% 50%;   
  -ms-animation:oblik 0.4s ease-in;   
  -ms-transform-origin: 50% 50%;   
  animation:oblik 0.4s ease-in;   
  transform-origin: 50% 50%;   
  width: 100px;   
  height: 100px;   
  border-radius: 50%;    
}   
@-webkit-keyframes oblik {   
  0% {opacity:1;-webkit-transform:scale(0);}   
  100% {opacity:0;-webkit-transform:scale(5);background-color: #006064;}      
}   
@-moz-keyframes oblik {   
  0% {opacity:1;-moz-transform:scale(0);}   
  100% {opacity:0;-moz-transform:scale(5);background-color: #006064;}      
}   
@-ms-keyframes oblik {   
  0% {opacity:1;-ms-transform:scale(0);}   
  100% {opacity:0;-ms-transform:scale(5);background-color: #006064;}      
}   
@keyframes oblik {   
  0% {opacity:1;transform:scale(0);}   
  100% {opacity:0;transform:scale(5);background-color: #006064;}      
}  #tag_cloud{padding:5px 20px 0px 20px;}
            .tag_css1 { font-size: 8px; }
            .tag_css2 { font-size: 12px; }
            .tag_css3 { font-size: 16px; }
            .tag_css4 { font-size: 24px; }