Windows 8 preloader (loading icon) using HTML5 and javascript without images

Question

I noticed a simple thing while looking at the screen of Windows 8 loading screen, there is a preloader (or loading icon) which is quite interesting, it has a bit of gravity/swin

Answer 1

Here is my pure CSS3 implementation with no Javascript in which I combined CSSload and Jan Rubio's codepen techniques for minimal markup and no id selectors:

HTML:

CSS:

.loader { position: relative; width: 64px; height: 64px; }
.loader .circle { position: absolute; width: 61px; height: 61px; opacity: 0; -moz-transform: rotate(225deg); -moz-animation: orbit 7.15s infinite; -webkit-transform: rotate(225deg); -webkit-animation: orbit 7.15s infinite; -ms-transform: rotate(225deg); -ms-animation: orbit 7.15s infinite; -o-transform: rotate(225deg); -o-animation: orbit 7.15s infinite; transform: rotate(225deg); animation: orbit 7.15s infinite; }
.loader .circle:after { content:''; position: absolute; width: 8px; height: 8px; background: #04C5DE; left: 0px; top: 0px; -moz-border-radius: 8px; -webkit-border-radius: 8px; -ms-border-radius: 8px; -o-border-radius: 8px; border-radius: 8px; }
.loader .circle:nth-child(1) { -moz-animation-delay: 1.56s; -webkit-animation-delay: 1.56s; -ms-animation-delay: 1.56s; -o-animation-delay: 1.56s; animation-delay: 1.56s; }
.loader .circle:nth-child(2) { -moz-animation-delay: 0.31s; -webkit-animation-delay: 0.31s; -ms-animation-delay: 0.31s; -o-animation-delay: 0.31s; animation-delay: 0.31s; }
.loader .circle:nth-child(3) { -moz-animation-delay: 0.62s; -webkit-animation-delay: 0.62s; -ms-animation-delay: 0.62s; -o-animation-delay: 0.62s; animation-delay: 0.62s; }
.loader .circle:nth-child(4) { -moz-animation-delay: 0.94s; -webkit-animation-delay: 0.94s; -ms-animation-delay: 0.94s; -o-animation-delay: 0.94s; animation-delay: 0.94s; }
.loader .circle:nth-child(5) { -moz-animation-delay: 1.25s; -webkit-animation-delay: 1.25s; -ms-animation-delay: 1.25s; -o-animation-delay: 1.25s; animation-delay: 1.25s; }

@-moz-keyframes orbit {
    0% { opacity: 1; z-index: 99; -moz-transform: rotate(180deg); -moz-animation-timing-function: ease-out; }
    7% { opacity: 1; -moz-transform: rotate(300deg); -moz-animation-timing-function: linear; -moz-origin: 0%; }
    30% { opacity: 1; -moz-transform: rotate(410deg); -moz-animation-timing-function: ease-in-out; -moz-origin: 7%; }
    39% { opacity: 1; -moz-transform: rotate(645deg); -moz-animation-timing-function: linear; -moz-origin: 30%; }
    70% { opacity: 1; -moz-transform: rotate(770deg); -moz-animation-timing-function: ease-out; -moz-origin: 39%; }
    75% { opacity: 1; -moz-transform: rotate(900deg); -moz-animation-timing-function: ease-out; -moz-origin: 70%; }
    76% { opacity: 0; -moz-transform: rotate(900deg); }
    100% { opacity: 0; -moz-transform: rotate(900deg); }
}

@-webkit-keyframes orbit {
    0% { opacity: 1; z-index: 99; -webkit-transform: rotate(180deg); -webkit-animation-timing-function: ease-out; }
    7% { opacity: 1; -webkit-transform: rotate(300deg); -webkit-animation-timing-function: linear; -webkit-origin: 0%; }
    30% { opacity: 1; -webkit-transform: rotate(410deg); -webkit-animation-timing-function: ease-in-out; -webkit-origin: 7%; }
    39% { opacity: 1; -webkit-transform: rotate(645deg); -webkit-animation-timing-function: linear; -webkit-origin: 30%; }
    70% { opacity: 1; -webkit-transform: rotate(770deg); -webkit-animation-timing-function: ease-out; -webkit-origin: 39%; }
    75% { opacity: 1; -webkit-transform: rotate(900deg); -webkit-animation-timing-function: ease-out; -webkit-origin: 70%; }
    76% { opacity: 0; -webkit-transform: rotate(900deg); }
    100% { opacity: 0; -webkit-transform: rotate(900deg); }
}

@-ms-keyframes orbit {
    0% { opacity: 1; z-index: 99; -ms-transform: rotate(180deg); -ms-animation-timing-function: ease-out; }
    7% { opacity: 1; -ms-transform: rotate(300deg); -ms-animation-timing-function: linear; -ms-origin: 0%; }
    30% { opacity: 1; -ms-transform: rotate(410deg); -ms-animation-timing-function: ease-in-out; -ms-origin: 7%; }
    39% { opacity: 1; -ms-transform: rotate(645deg); -ms-animation-timing-function: linear; -ms-origin: 30%; }
    70% { opacity: 1; -ms-transform: rotate(770deg); -ms-animation-timing-function: ease-out; -ms-origin: 39%; }
    75% { opacity: 1; -ms-transform: rotate(900deg); -ms-animation-timing-function: ease-out; -ms-origin: 70%; }
    76% { opacity: 0; -ms-transform: rotate(900deg); }
    100% { opacity: 0; -ms-transform: rotate(900deg); }
}

@-o-keyframes orbit {
    0% { opacity: 1; z-index: 99; -o-transform: rotate(180deg); -o-animation-timing-function: ease-out; }
    7% { opacity: 1; -o-transform: rotate(300deg); -o-animation-timing-function: linear; -o-origin: 0%; }
    30% { opacity: 1; -o-transform: rotate(410deg); -o-animation-timing-function: ease-in-out; -o-origin: 7%; }
    39% { opacity: 1; -o-transform: rotate(645deg); -o-animation-timing-function: linear; -o-origin: 30%; }
    70% { opacity: 1; -o-transform: rotate(770deg); -o-animation-timing-function: ease-out; -o-origin: 39%; }
    75% { opacity: 1; -o-transform: rotate(900deg); -o-animation-timing-function: ease-out; -o-origin: 70%; }
    76% { opacity: 0; -o-transform: rotate(900deg); }
    100% { opacity: 0; -o-transform: rotate(900deg); }
}

@keyframes orbit {
    0% { opacity: 1; z-index: 99; transform: rotate(180deg); animation-timing-function: ease-out; }
    7% { opacity: 1; transform: rotate(300deg); animation-timing-function: linear; origin: 0%; }
    30% { opacity: 1; transform: rotate(410deg); animation-timing-function: ease-in-out; origin: 7%; }
    39% { opacity: 1; transform: rotate(645deg); animation-timing-function: linear; origin: 30%; }
    70% { opacity: 1; transform: rotate(770deg); animation-timing-function: ease-out; origin: 39%; }
    75% { opacity: 1; transform: rotate(900deg); animation-timing-function: ease-out; origin: 70%; }
    76% { opacity: 0; transform: rotate(900deg); }
    100% { opacity: 0; transform: rotate(900deg); }
}