body {
    font-family: Roboto, Arial, sans-serif;
}

.container {
    width: 80%;
    margin: auto;
    display: block;
    box-sizing: border-box;
}

.title {
    background-color: green;
    padding: 10px;
    color: white;
    box-sizing: border-box;
    text-align: center;
    width: 100%;
    margin-bottom: 1em;
    border-radius: 5px;
}

@media (max-width: 480px)
{
    .container
    {
        display:block;
        box-sizing:border-box;
    }
}