.introboxdown {
    animation-name: example1;
    animation-duration: 1s;
}
@keyframes example1 {
0% {
transform: translateY(-60px);
opacity: 0;
}
100% {
transform: translateY(0);
opacity: 1;
}
}

.introboxup {
    animation-name: example2;
    animation-duration: 2s;
}
@keyframes example2 {
0% {
transform: translateY(50px);
opacity: 0;
}
100% {
transform: translateY(0);
opacity: 1;
}
}