LoadingAnimation

loading.css

* {
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    box-sizing: border-box;
}

html {
    height: 100%;
}

body {
    background: #333;
    position: relative;
    height: 100%;
    margin: 0px;
}

@-webkit-keyframes clockwise {
    0% {
        -moz-transform: rotate(0deg);
        -ms-transform: rotate(0deg);
        -webkit-transform: rotate(0deg);
        transform: rotate(0deg);
    }
    100% {
        -moz-transform: rotate(360deg);
        -ms-transform: rotate(360deg);
        -webkit-transform: rotate(360deg);
        transform: rotate(360deg);
    }
}

@-moz-keyframes clockwise {
    0% {
        -moz-transform: rotate(0deg);
        -ms-transform: rotate(0deg);
        -webkit-transform: rotate(0deg);
        transform: rotate(0deg);
    }
    100% {
        -moz-transform: rotate(360deg);
        -ms-transform: rotate(360deg);
        -webkit-transform: rotate(360deg);
        transform: rotate(360deg);
    }
}

@-webkit-keyframes counter-clockwise {
    0% {
        -moz-transform: rotate(0deg);
        -ms-transform: rotate(0deg);
        -webkit-transform: rotate(0deg);
        transform: rotate(0deg);
    }
    100% {
        -moz-transform: rotate(-360deg);
        -ms-transform: rotate(-360deg);
        -webkit-transform: rotate(-360deg);
        transform: rotate(-360deg);
    }
}

@-moz-keyframes counter-clockwise {
    0% {
        -moz-transform: rotate(0deg);
        -ms-transform: rotate(0deg);
        -webkit-transform: rotate(0deg);
        transform: rotate(0deg);
    }
    100% {
        -moz-transform: rotate(-360deg);
        -ms-transform: rotate(-360deg);
        -webkit-transform: rotate(-360deg);
        transform: rotate(-360deg);
    }
}

.container {
    position: absolute;
    top: 50%;
    left: 50%;
    margin-left: -100px;
    height: 150px;
    width: 200px;
    margin-top: -75px;
}

.gearbox {
    background: #111;
    height: 150px;
    width: 200px;
    position: relative;
    border: none;
    overflow: hidden;
    -moz-border-radius: 6px;
    -webkit-border-radius: 6px;
    border-radius: 6px;
    -moz-box-shadow: 0px 0px 0px 1px rgba(255, 255, 255, 0.1);
    -webkit-box-shadow: 0px 0px 0px 1px rgba(255, 255, 255, 0.1);
    box-shadow: 0px 0px 0px 1px rgba(255, 255, 255, 0.1);
}

.gearbox .overlay {
    -moz-border-radius: 6px;
    -webkit-border-radius: 6px;
    border-radius: 6px;
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 10;
    -moz-box-shadow: inset 0px 0px 20px black;
    -webkit-box-shadow: inset 0px 0px 20px black;
    box-shadow: inset 0px 0px 20px black;
    -moz-transition: background 0.2s;
    -o-transition: background 0.2s;
    -webkit-transition: background 0.2s;
    transition: background 0.2s;
}

.gearbox.turn .overlay {
    background: transparent;
}

.gear {
    position: absolute;
    height: 60px;
    width: 60px;
    -moz-box-shadow: 0px -1px 0px 0px #888888, 0px 1px 0px 0px black;
    -webkit-box-shadow: 0px -1px 0px 0px #888888, 0px 1px 0px 0px black;
    box-shadow: 0px -1px 0px 0px #888888, 0px 1px 0px 0px black;
    -moz-border-radius: 30px;
    -webkit-border-radius: 30px;
    border-radius: 30px;
}

.gear.large {
    height: 120px;
    width: 120px;
    -moz-border-radius: 60px;
    -webkit-border-radius: 60px;
    border-radius: 60px;
}

.gear.large:after {
    height: 96px;
    width: 96px;
    -moz-border-radius: 48px;
    -webkit-border-radius: 48px;
    border-radius: 48px;
    margin-left: -48px;
    margin-top: -48px;
}

.gear.one {
    top: 12px;
    left: 10px;
}

.gear.two {
    top: 61px;
    left: 60px;
}

.gear.three {
    top: 110px;
    left: 10px;
}

.gear.four {
    top: 13px;
    left: 128px;
}

.gear:after {
    content: "";
    position: absolute;
    height: 36px;
    width: 36px;
    -moz-border-radius: 36px;
    -webkit-border-radius: 36px;
    border-radius: 36px;
    background: #111;
    top: 50%;
    left: 50%;
    margin-left: -18px;
    margin-top: -18px;
    z-index: 3;
    -moz-box-shadow: 0px 0px 10px rgba(255, 255, 255, 0.1), inset 0px 0px 10px rgba(0, 0, 0, 0.1), inset 0px 2px 0px 0px #090909, inset 0px -1px 0px 0px #888888;
    -webkit-box-shadow: 0px 0px 10px rgba(255, 255, 255, 0.1), inset 0px 0px 10px rgba(0, 0, 0, 0.1), inset 0px 2px 0px 0px #090909, inset 0px -1px 0px 0px #888888;
    box-shadow: 0px 0px 10px rgba(255, 255, 255, 0.1), inset 0px 0px 10px rgba(0, 0, 0, 0.1), inset 0px 2px 0px 0px #090909, inset 0px -1px 0px 0px #888888;
}

.gear-inner {
    position: relative;
    height: 100%;
    width: 100%;
    background: #555;
    -webkit-animation-iteration-count: infinite;
    -moz-animation-iteration-count: infinite;
    -moz-border-radius: 30px;
    -webkit-border-radius: 30px;
    border-radius: 30px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.large .gear-inner {
    -moz-border-radius: 60px;
    -webkit-border-radius: 60px;
    border-radius: 60px;
}

.gear.one .gear-inner {
    -webkit-animation: counter-clockwise 3s infinite linear;
    -moz-animation: counter-clockwise 3s infinite linear;
}

.gear.two .gear-inner {
    -webkit-animation: clockwise 3s infinite linear;
    -moz-animation: clockwise 3s infinite linear;
}

.gear.three .gear-inner {
    -webkit-animation: counter-clockwise 3s infinite linear;
    -moz-animation: counter-clockwise 3s infinite linear;
}

.gear.four .gear-inner {
    -webkit-animation: counter-clockwise 6s infinite linear;
    -moz-animation: counter-clockwise 6s infinite linear;
}

.gear-inner .bar {
    background: #555;
    height: 16px;
    width: 76px;
    position: absolute;
    left: 50%;
    margin-left: -38px;
    top: 50%;
    margin-top: -8px;
    -moz-border-radius: 2px;
    -webkit-border-radius: 2px;
    border-radius: 2px;
    border-left: 1px solid rgba(255, 255, 255, 0.1);
    border-right: 1px solid rgba(255, 255, 255, 0.1);
}

.large .gear-inner .bar {
    margin-left: -68px;
    width: 136px;
}

.gear-inner .bar:nth-child(2) {
    -moz-transform: rotate(60deg);
    -ms-transform: rotate(60deg);
    -webkit-transform: rotate(60deg);
    transform: rotate(60deg);
}

.gear-inner .bar:nth-child(3) {
    -moz-transform: rotate(120deg);
    -ms-transform: rotate(120deg);
    -webkit-transform: rotate(120deg);
    transform: rotate(120deg);
}

.gear-inner .bar:nth-child(4) {
    -moz-transform: rotate(90deg);
    -ms-transform: rotate(90deg);
    -webkit-transform: rotate(90deg);
    transform: rotate(90deg);
}

.gear-inner .bar:nth-child(5) {
    -moz-transform: rotate(30deg);
    -ms-transform: rotate(30deg);
    -webkit-transform: rotate(30deg);
    transform: rotate(30deg);
}

.gear-inner .bar:nth-child(6) {
    -moz-transform: rotate(150deg);
    -ms-transform: rotate(150deg);
    -webkit-transform: rotate(150deg);
    transform: rotate(150deg);
}

h1 {
    font-family: "Helvetica";
    text-align: center;
    text-transform: uppercase;
    color: #888;
    font-size: 19px;
    padding-top: 10px;
    text-shadow: 1px 1px 0px #111;
}

loading.html

<div id="loading">
    <div class="container">
        <div class="gearbox">
            <div class="overlay"></div>
            <div class="gear one">
                <div class="gear-inner">
                    <div class="bar"></div>
                    <div class="bar"></div>
                    <div class="bar"></div>
                </div>
            </div>
            <div class="gear two">
                <div class="gear-inner">
                    <div class="bar"></div>
                    <div class="bar"></div>
                    <div class="bar"></div>
                </div>
            </div>
            <div class="gear three">
                <div class="gear-inner">
                    <div class="bar"></div>
                    <div class="bar"></div>
                    <div class="bar"></div>
                </div>
            </div>
            <div class="gear four large">
                <div class="gear-inner">
                    <div class="bar"></div>
                    <div class="bar"></div>
                    <div class="bar"></div>
                    <div class="bar"></div>
                    <div class="bar"></div>
                    <div class="bar"></div>
                </div>
            </div>
        </div>
        <h1>Loading...</h1>
    </div>
</div>