I have a button with a box-shadow that makes it look like it's floating, and I would like to make a pressing effect when I click on it:
Code(CSS):
#startBtn
{
    font-family: OpenSans;
    color: #FFFFFF;
    background-color: #00FF7C;
    border: 1px solid #00FF7C;
    border-radius: 5px;
    box-shadow: 0px 5px 0px #00823F;
}
Code(HTML):
<input type="button" id="startBtn" value="Let's begin">
Screenshot:

 
     
     
     
    