I guess you mean something like this demo ?
If so you have to use the @keyframes
element of CSS. More info on MDN or on CSS-Tricks.
CSS
.circle {
background: rgb(255, 255, 255);
border-radius: 100%;
cursor: pointer;
position: relative;
margin: 0 auto;
width: 15em;
height: 15em;
overflow: hidden;
-webkit-transform: translateZ(0);
-moz-transform: translateZ(0);
-ms-transform: translateZ(0);
transform: translateZ(0);
}
.circle h1 {
font-family:'Lato', sans-serif;
font-weight: 900;
font-size: 1.6em;
line-height: 8.2em;
text-align: center;
text-transform: uppercase;
-webkit-font-smoothing: antialiased;
-webkit-user-select: none;
-moz-user-select: none;
-ms-user-select: none;
user-select: none;
-webkit-animation: showText 2s infinite; /* Safari/Chrome 4+ */
-moz-animation: showText 2s infinite; /* Firefox 5+ */
-o-animation: showText 2s infinite; /* Opera 12+ */
animation: showText 2s infinite; /* IE 10+ */
animation-timing-function: ease-in-out;
/*
** -webkit-transition: color 0.8s ease-in-out;
** -moz-transition: color 0.8s ease-in-out;
** -ms-transition: color 0.8s ease-in-out;
** transition: color 0.8s ease-in-out;
*/
}
.circle:before, .circle:after {
border-radius: 100%;
content:"";
position: absolute;
top: 0;
left: 0;
width: inherit;
height: inherit;
-webkit-animation: moveCircle 2s infinite; /* Safari/Chrome 4+ */
-moz-animation: moveCircle 2s infinite; /* Firefox 5+ */
-o-animation: moveCircle 2s infinite; /* Opera 12+ */
animation: moveCircle 2s infinite; /* IE 10+ */
/*
** -webkit-transition: box-shadow 0.75s;
** -moz-transition: box-shadow 0.75s;
** -ms-transition: box-shadow 0.75s;
** transition: box-shadow 0.75s;
*/
}
.circle:after {
-webkit-transform: rotate(45deg);
-moz-transform: rotate(45deg);
transform: rotate(45deg);
}
@-webkit-keyframes moveCircle {
0% {
box-shadow: inset 10.6em 0 0 rgba(30, 140, 209, 0.2), inset 0 10.6em 0 rgba(30, 140, 209, 0.2), inset -10.6em 0 0 rgba(30, 140, 209, 0.2), inset 0 -10.6em 0 rgba(30, 140, 209, 0.2);
}
100% {
box-shadow: inset 0.86em 0 0 rgba(255, 0, 0, 0.5), inset 0 0.86em 0 rgba(252, 150, 0, 0.5), inset -0.86em 0 0 rgba(0, 255, 0, 0.5), inset 0 -0.86em 0 rgba(0, 150, 255, 0.5);
}
}
@-moz-keyframes moveCircle {
0% {
box-shadow: inset 10.6em 0 0 rgba(30, 140, 209, 0.2), inset 0 10.6em 0 rgba(30, 140, 209, 0.2), inset -10.6em 0 0 rgba(30, 140, 209, 0.2), inset 0 -10.6em 0 rgba(30, 140, 209, 0.2);
}
100% {
box-shadow: inset 0.86em 0 0 rgba(255, 0, 0, 0.5), inset 0 0.86em 0 rgba(252, 150, 0, 0.5), inset -0.86em 0 0 rgba(0, 255, 0, 0.5), inset 0 -0.86em 0 rgba(0, 150, 255, 0.5);
}
}
@-o-keyframes moveCircle {
0% {
box-shadow: inset 10.6em 0 0 rgba(30, 140, 209, 0.2), inset 0 10.6em 0 rgba(30, 140, 209, 0.2), inset -10.6em 0 0 rgba(30, 140, 209, 0.2), inset 0 -10.6em 0 rgba(30, 140, 209, 0.2);
}
100% {
box-shadow: inset 0.86em 0 0 rgba(255, 0, 0, 0.5), inset 0 0.86em 0 rgba(252, 150, 0, 0.5), inset -0.86em 0 0 rgba(0, 255, 0, 0.5), inset 0 -0.86em 0 rgba(0, 150, 255, 0.5);
}
}
@keyframes moveCircle {
0% {
box-shadow: inset 10.6em 0 0 rgba(30, 140, 209, 0.2), inset 0 10.6em 0 rgba(30, 140, 209, 0.2), inset -10.6em 0 0 rgba(30, 140, 209, 0.2), inset 0 -10.6em 0 rgba(30, 140, 209, 0.2);
}
100% {
box-shadow: inset 0.86em 0 0 rgba(255, 0, 0, 0.5), inset 0 0.86em 0 rgba(252, 150, 0, 0.5), inset -0.86em 0 0 rgba(0, 255, 0, 0.5), inset 0 -0.86em 0 rgba(0, 150, 255, 0.5);
}
}
@-webkit-keyframes showText {
0% {
color: rgba(189, 185, 199, 0);
}
100% {
color: rgba(185, 185, 185, 1);
}
}
@-moz-keyframes showText {
0% {
color: rgba(189, 185, 199, 0);
}
100% {
color: rgba(185, 185, 185, 1);
}
}
@-o-keyframes showText {
0% {
color: rgba(189, 185, 199, 0);
}
100% {
color: rgba(185, 185, 185, 1);
}
}
@keyframes showText {
0% {
color: rgba(189, 185, 199, 0);
}
100% {
color: rgba(185, 185, 185, 1);
}
}