Create a revolving orbit with CSS

<div class="spinning logo started"><div class="rings"><span class="tilt one"><span class="ring one"><span class="texture"></span></span></span><span class="tilt two"><span class="ring two"><span class="texture"></span></span></span><span class="tilt three"><span class="ring three"><span class="texture"></span></span></span><span class="tilt four"><span class="ring four"><span class="texture"></span></span></span></div><span class="letter"></span></div>


.logo .rings {
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 100%;
    -webkit-animation-name: ringspin;
    animation-name: ringspin;
    -webkit-animation-duration: 7000ms;
    animation-duration: 7000ms;
    -webkit-animation-iteration-count: infinite;
    -webkit-animation-timing-function: linear;
    animation-name: ringspin;
    animation-duration: 7000ms;
    animation-iteration-count: infinite;
    animation-timing-function: linear;
}

.square .contents .logo .letter {
    background-size: 36px 36px;
}
.logo.started .letter {
    opacity: 1;
    -webkit-transform: scale(1) translateZ(1px) rotateY(0);
    transform: scale(1) translateZ(1px) rotateY(0);
}
.logo .letter {
    background: url(../images/logo/g.png) no-repeat center center;
    background-size: 64px 64px;
    background-size: 48px 48px;
    display: block;
    margin: -32px 0 0 -32px;
    position: absolute;
    top: 50%;
    left: 50%;
    text-align: center;
    height: 64px;
    width: 64px;
    transition: all 800ms ease-out;
    opacity: 0;
    -webkit-transform: scale(0.12) translateZ(1px) rotateY(200deg);
    transform: scale(0.12) translateZ(1px) rotateY(200deg);
}