html,
body,
#bubbles { height: 100% }
body
#bubbles { padding: 100px 0 }
.bubble {
    width: 60px;
    height: 60px;
    background: #ffffff;
    border-radius: 200px;
    -moz-border-radius: 200px;
    -webkit-border-radius: 200px;
    position: absolute;
}

.x1 {
    -webkit-transform: scale(0.9);
    -moz-transform: scale(0.9);
    transform: scale(0.9);
    opacity: 0.2;
    -webkit-animation: moveclouds 6s linear infinite, sideWays 4s ease-in-out infinite alternate;
    -moz-animation: moveclouds 6s linear infinite, sideWays 4s ease-in-out infinite alternate;
    -o-animation: moveclouds 6s linear infinite, sideWays 4s ease-in-out infinite alternate;
}

.x2 {
    left: 200px;
    -webkit-transform: scale(0.6);
    -moz-transform: scale(0.6);
    transform: scale(0.6);
    opacity: 0.5;
    -webkit-animation: moveclouds 10s linear infinite, sideWays 5s ease-in-out infinite alternate;
    -moz-animation: moveclouds 10s linear infinite, sideWays 5s ease-in-out infinite alternate;
    -o-animation: moveclouds 10s linear infinite, sideWays 5s ease-in-out infinite alternate;
}
.x3 {
    left: 350px;
    -webkit-transform: scale(0.8);
    -moz-transform: scale(0.8);
    transform: scale(0.8);
    opacity: 0.3;
    -webkit-animation: moveclouds 14s linear infinite, sideWays 4s ease-in-out infinite alternate;
    -moz-animation: moveclouds 14s linear infinite, sideWays 4s ease-in-out infinite alternate;
    -o-animation: moveclouds 14s linear infinite, sideWays 4s ease-in-out infinite alternate;
}
.x4 {
    left: 470px;
    -webkit-transform: scale(0.75);
    -moz-transform: scale(0.75);
    transform: scale(0.75);
    opacity: 0.35;
    -webkit-animation: moveclouds 8s linear infinite, sideWays 2s ease-in-out infinite alternate;
    -moz-animation: moveclouds 8s linear infinite, sideWays 2s ease-in-out infinite alternate;
    -o-animation: moveclouds 8s linear infinite, sideWays 2s ease-in-out infinite alternate;
}
.x5 {
    left: 150px;
    -webkit-transform: scale(0.8);
    -moz-transform: scale(0.8);
    transform: scale(0.8);
    opacity: 0.3; 
    -webkit-animation: moveclouds 7s linear infinite, sideWays 1s ease-in-out infinite alternate;
    -moz-animation: moveclouds 7s linear infinite, sideWays 1s ease-in-out infinite alternate;
    -o-animation: moveclouds 7s linear infinite, sideWays 1s ease-in-out infinite alternate;
}
@-webkit-keyframes moveclouds { 
    0% { 
        top: 500px;
    }
    100% { 
        top: -500px;
    }
}

@-webkit-keyframes sideWays { 
    0% { 
        margin-left:0px;
    }
    100% { 
        margin-left:50px;
    }
}

@-moz-keyframes moveclouds {     
    0% { 
        top: 500px;
    }

    100% { 
        top: -500px;
    }
}

@-moz-keyframes sideWays {
    0% {
        margin-left:0px;
    }
    100% {
        margin-left:50px;
    }
}
@-o-keyframes moveclouds {
    0% { 
        top: 500px;
    }
    100% { 
        top: -500px;
    }
}

@-o-keyframes sideWays {
    0% {
        margin-left:0px;
    }
    100% {
        margin-left:50px;
    }
}