style.css

.container {
    width: 500px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
}

.foto-container {
    width: 300px;
    height: 150px;
    margin-left: auto;
    margin-right: auto;
    background-color: green;
}

.foto {
    width: 100%;
    height: 100%;
}