       <div class="card-panel  blue-grey lighten-3 right-align screen">
                <span class="black-text result">0</span>
            </div>
            <div class="buttons">
                <div class="col s3"><button type="button" class="waves-effect waves-light btn">C</button></div>
                <div class="col s3"><button type="button" class="waves-effect waves-light btn">+/-</button></div>
                <div class="col s3"><button type="button" class="waves-effect waves-light btn">%</button