Button background not changing on hover - html

Question

I've created a button as a link using the usual methods, however, I am encountering a curious issue where the background colour is not changing on hover, when it should.
I've probably missed something really obvious, but I can't for the life of me find it.
The code in question is:
.downloadbtn {
color: white;
display: block;
margin: auto;
width: 250px;
height: 60px;
margin-top: 30px;
padding: 20px;
background: #06bce4;
background: -moz-linear-gradient(top, #06bce4 0%, #0589d4 100%);
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#06bce4), color-stop(100%,#0589d4));
background: -webkit-linear-gradient(top, #06bce4 0%,#0589d4 100%);
background: -o-linear-gradient(top, #06bce4 0%,#0589d4 100%);
background: -ms-linear-gradient(top, #06bce4 0%,#0589d4 100%);
background: linear-gradient(to bottom, #06bce4 0%,#0589d4 100%);
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#06bce4', endColorstr='#0589d4',GradientType=0 );
border: 1px solid #076ca0;
border-radius: 4px;
-webkit-box-shadow: inset 0px 1px 0px 0px rgba(64, 209, 236, 1);
-moz-box-shadow: inset 0px 1px 0px 0px rgba(64, 209, 236, 1);
box-shadow: inset 0px 1px 0px 0px rgba(64, 209, 236, 1);
-webkit-animation-delay: 2s;
-webkit-animation-iteration-count: infinite;
-webkit-animation-duration: 6s;
-moz-animation-delay: 2s;
-moz-animation-iteration-count: infinite;
-webkit-animation-duration: 6s;
}
.downloadbtn :hover {
background: green;
}
A JSFiddle is here: http://jsfiddle.net/4Xxaf/

Answer 1

Updated fiddle. You added a space between the selector and :hover http://jsfiddle.net/4Xxaf/1/

Answer 2

Remove the space in your code
.downloadbtn:hover{
background: green;
}