img {
    display: block;
    font-family: Helvetica, Arial, sans-serif;
    font-weight: 300;
    height: auto;
    line-height: 2;
    position: relative;
    text-align: center;
    width: 100%;
}
img:before {
    content: "We're sorry, the image below is missing :(";
    display: block;
    margin-bottom: 10px;
}
img:after {
    content: "(url: " attr(src) ")";
    display: block;
    font-size: 12px;
}