local.css

html::after {
        content: "DEVELOPMENT";
        text-transform: uppercase;
        font-family: monospace;
        font-size: 15px;
        font-weight: bold;
        text-align: center;
        color: white;

        display: block;
        width: 200px;
        position: fixed;
        top: 0;
        right: 0;
        margin-top: 30px;
        margin-right: -55px;
        background-color: RED;
        border: 5px solid red;
        transform: rotate(45deg);
        box-shadow: 0 1px 0 1px rgba(0,0,0,0.1);
}