  @-ms-keyframes fadein_birds {
                from {
                    opacity: 0;
                    left: 56.8%;
                    top: 0;
                }

                to {
                    opacity: 1;
                    left: 56.8%;
                    top: 27.4%;
                }
            }

            #mountain-left {
                position: absolute;
                left: 10.66%;
                top: 63.01%;
                width: 25.46%;
                height: 35.61%;
       