.water-container{position:relative;width:200px;height:200px;background-color:#0099cc;overflow:hidden}.water{position:absolute;bottom:0;width:100%;height:50px;background-color:#66ccff;animation:waterAnimation 2s infinite cubic-bezier(0.4,0.0,0.2,1)}@keyframes waterAnimation{0%,100%{transform:translateY(0)}50%{transform:translateY(-20px)}}