Edit in JSFiddle

@-webkit-keyframes spin {
    to {
        -webkit-transform: rotate(360deg);
    }
}
@-moz-keyframes spin {
    to {
        -moz-transform: rotate(360deg);
    }
}
@-ms-keyframes spin {
    to {
        -ms-transform: rotate(360deg);
    }
}
@-o-keyframes spin {
    to {
        -o-transform: rotate(360deg);
    }
}
@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}
.spinner {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    border: 2px solid rgba(255, 0, 0, 1);
    border-top: 2px solid transparent;
    -webkit-animation: spin 1s infinite linear;
    -moz-animation: spin 1s infinite linear;
    -ms-animation: spin 1s infinite linear;
    -o-animation: spin 1s infinite linear;
    animation: spin 1s infinite linear;
}