Shadow Blink Using CSS

How to create flashing/glowing div box using CSS3?

@keyframes blink {
    0% {
        box-shadow: 0 0 20px #EC7A44;
    }
    50% {
        box-shadow: none;
    }
    100% {
        box-shadow: 0 0 20px #EC7A44;
    }
}
@-webkit-keyframes blink {
    0% {
        box-shadow: 0 0 20px #EC7A44;
    }
    50% {
        box-shadow: 0 0 0;
    }
    100% {
        box-shadow: 0 0 20px #EC7A44;
    }
}
.blink {
    -webkit-animation: blink 1.0s linear infinite;
    -moz-animation: blink 1.0s linear infinite;
    -ms-animation: blink 1.0s linear infinite;
    -o-animation: blink 1.0s linear infinite;
    animation: blink 1.0s linear infinite;
}

DEMO