.Physical-modeling-method{width:px; height:px ;}
.Ball-motion-modeling{width:px; height:px ;}
.Light-beam-modeling{width:px; height:px ;}
.Modeling-seeing-object{width:px; height:px ;}
.Parachutist-modeling{width:px; height:px ;}
.Modeling-body-pushing{width:px; height:px ;}