Uses CSS3 attributes and psuedo elements to create a simple play button for web interfaces.
.video-btn {
background: #333;
width: 20%;
height: 20%;
left: 50%;
top: 50%;
margin-top: -30px;
margin-left: -30px;
border-radius: 50px;
}
.video-btn::before {
content: "";
position: absolute;
left: 50%;
top: 50%;
width: 0;
height: 0;
margin-top: -15.5px;
margin-left: -11px;
border-top: 15px solid transparent;
border-bottom: 15px solid transparent;
border-left: 28px solid #FFF;
}