html, body {
                width: 100%;
                height: 100%;
            }

            body {
                background-color: #ffffff;
                margin: 0;
                overflow: hidden;
                font-family: arial;
            }

            #blocker {

                position: absolute;

                width: 100%;
                height: 100%;

                background-color: rgba(0,0,0,0.5);

            }

            #instructions {

                width: 100%;
                height: 100%;

                display: -webkit-box;
                display: -moz-box;
                display: box;

                -webkit-box-orient: horizontal;
                -moz-box-orient: horizontal;
                box-orient: horizontal;

                -webkit-box-pack: center;
                -moz-box-pack: center;
                box-pack: center;

                -webkit-box-align: center;
                -moz-box-align: center;
                box-align: center;

                color: #ffffff;
                text-align: center;

                cursor: pointer;

            }