how to make pictures fade in and out and in again html code example

Example: how to fade out images html css

.fade-out {  animation: fadeOut ease 8s;  -webkit-animation: fadeOut ease 8s;  -moz-animation: fadeOut ease 8s;  -o-animation: fadeOut ease 8s;  -ms-animation: fadeOut ease 8s;}@keyframes fadeOut {  0% {    opacity:1;  }  100% {    opacity:0;  }}@-moz-keyframes fadeOut {  0% {    opacity:1;  }  100% {    opacity:0;  }}@-webkit-keyframes fadeOut {  0% {    opacity:1;  }  100% {    opacity:0;  }}@-o-keyframes fadeOut {  0% {    opacity:1;  }  100% {    opacity:0;  }}@-ms-keyframes fadeOut {  0% {    opacity:1;  }  100% {    opacity:0;}