<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
@-webkit-keyframes fadein {
from {
opacity: 0;
}
to {
opacity: 1;
}
}
@-moz-keyframes fadein {
from {
opacity: 0;
}
to {
opacity: 1;
}
}
@keyframes fadein {
from {
opacity: 0;
}
to {
opacity: 1;
}
}
#animation1 {
height: 120px;
width: 120px;
background: #5bd97d;
opacity: 0;
-webkit-animation: fadein 1s ease-in alternate;
-moz-animation: fadein 1s ease-in alternate;