#titre1{
    animation-name: anim1;
    animation-duration: 4s;
    animation-iteration-count: infinite;
    animation-direction: alternate;
}
@keyframes anim1 {
    from {
        margin-left: 100%;
        width: 100%;
    }
    to{
        margin-left: 0%;
        width: 100%;
    }

}
#pa1:hover{
 color: red;
}