#gdpr-cookie-message {
    border:1px solid orange;
    background-color:lightgray;
    margin:4px;
    padding:4px;
    color:black;
}

    #gdpr-cookie-message a {
        /* your css here */
    }

        #gdpr-cookie-message a:hover {
            /* your css here */
        }

    #gdpr-cookie-message h4 {
        /* your css here */
    }

    #gdpr-cookie-message p:last-child {
        /* your css here */
    }

    #gdpr-cookie-message button {
        /* your css here */
    }

        #gdpr-cookie-message button:hover {
            /* your css here */
        }