.sky{height:50vh;position:absolute;overflow:hidden;top:45%;width:100%}.clouds_one{background:url(cloud_one.png);position:absolute;left:0;top:0;height:100%;width:300%;-webkit-animation:cloud_one 50s linear infinite;-moz-animation:cloud_one 50s linear infinite;-o-animation:cloud_one 50s linear infinite;-webkit-transform:translate3d(0,0,0);-moz-transform:translate3d(0,0,0);-o-transform:translate3d(0,0,0)}.clouds_two{background:url(cloud_two.png);position:absolute;left:0;top:0;height:100%;width:300%;-webkit-animation:cloud_two 75s linear infinite;-moz-animation:cloud_two 75s linear infinite;-o-animation:cloud_two 75s linear infinite;-webkit-transform:translate3d(0,0,0);-moz-transform:translate3d(0,0,0);-o-transform:translate3d(0,0,0)}.clouds_three{background:url(cloud_three.png);position:absolute;left:0;top:0;height:100%;width:300%;-webkit-animation:cloud_three 100s linear infinite;-moz-animation:cloud_three 100s linear infinite;-o-animation:cloud_three 100s linear infinite;-webkit-transform:translate3d(0,0,0);-moz-transform:translate3d(0,0,0);-o-transform:translate3d(0,0,0)}@-webkit-keyframes sky_background{0%{background:#007fd5;color:#007fd5}50%{background:#000;color:#a3d9ff}100%{background:#007fd5;color:#007fd5}}@-webkit-keyframes moon{0%{opacity:0;left:-200% -moz-transform:scale(0.5);-webkit-transform:scale(.5)}50%{opacity:1;-moz-transform:scale(1);left:0% bottom:250px;-webkit-transform:scale(1)}100%{opacity:0;bottom:500px;-moz-transform:scale(.5);-webkit-transform:scale(.5)}}@-webkit-keyframes cloud_one{0%{left:0}100%{left:-200%}}@-webkit-keyframes cloud_two{0%{left:0}100%{left:-200%}}@-webkit-keyframes cloud_three{0%{left:0}100%{left:-200%}}@-moz-keyframes sky_background{0%{background:#007fd5;color:#007fd5}50%{background:#000;color:#a3d9ff}100%{background:#007fd5;color:#007fd5}}@-moz-keyframes moon{0%{opacity:0;left:-200% -moz-transform:scale(0.5);-webkit-transform:scale(.5)}50%{opacity:1;-moz-transform:scale(1);left:0% bottom:250px;-webkit-transform:scale(1)}100%{opacity:0;bottom:500px;-moz-transform:scale(.5);-webkit-transform:scale(.5)}}@-moz-keyframes cloud_one{0%{left:0}100%{left:-200%}}@-moz-keyframes cloud_two{0%{left:0}100%{left:-200%}}@-moz-keyframes cloud_three{0%{left:0}100%{left:-200%}}