.css_animation{  
        height:20px;  
        width:20px;  
        border-radius: 10px;  
        background: rgba(250, 0, 0, 0.9);  
        transform: scale(0);  
        animation: myfirst 3s;  
        animation-iteration-count: infinite;  
    }  
    .color0{background: rgba(0, 255, 0, 0.9);}
    .color1{background: rgba(255, 0, 0, 0.9);}
    .color2{background: rgba(255, 125, 0, 0.9);}
    .color3{background: rgba(0, 0, 255, 0.9);}
  
    @keyframes myfirst{  
        to{  
            transform: scale(2);  
            background: rgba(0, 0, 0, 0);  
        }  
    }