style:
.loding {
100%;
height: 100%;
}
.bg{
100%;
height: 100%;
margin: 0;
overflow: hidden;
background: #000；
position: relative;
z-index: 999;
}
#stars {
margin: 0 auto;
max- 1600px;
position: fixed;
top: 0;
left: 0;
right: 0;
bottom: 0;
z-index: 2;
}
.star {
display: block;
1px;
background: transparent;
position: relative;
opacity: 0;
/*过渡动画*/
animation: star-fall 3s linear infinite;
-webkit-animation: star-fall 3s linear infinite;
-moz-animation: star-fall 3s linear infinite;
}
.star:after {
content: '';
display: block;
border: 0px solid #fff;
border- 0px 90px 2px 90px;
border-color: transparent transparent transparent rgba(255, 255, 255, 1);
box-shadow: 0 0 1px 0 rgba(255, 255, 255, .1);
/*变形*/
transform: rotate(-45deg) translate3d(1px, 3px, 0);
-webkit-transform: rotate(-45deg) translate3d(1px, 3px, 0);
-moz-transform: rotate(-45deg) translate3d(1px, 3px, 0);
transform-origin: 0% 100%;
-webkit-transform-origin: 0% 100%;
-moz-transform-origin: 0% 100%;
}
@keyframes star-fall {
0% {
opacity: 0;
transform: scale(0.5) translate3d(0, 0, 0);
-webkit-transform: scale(0.5) translate3d(0, 0, 0);
-moz-transform: scale(0.5) translate3d(0, 0, 0);
}
50% {
opacity: 1;
transform: translate3d(-200px, 200px, 0);
-webkit-transform: translate3d(-200px, 200px, 0);
-moz-transform: translate3d(-200px, 200px, 0);
}
100% {
opacity: 0;
transform: scale(1.2) translate3d(-300px, 300px, 0);
-webkit-transform: scale(1.2) translate3d(-300px, 300px, 0);
-moz-transform: scale(1.2) translate3d(-300px, 300px, 0);
}
}
body:
<div class="loding">
<div class="bg">
<div id="stars">
<div class="star" style="top: 0px;left: 300px;"></div>
<div class="star" style="top: 0px;left: 130px;"></div>
</div>
</div>
</div>
js:
(function () {
let stars = document.getElementById('stars');
for (var j = 0; j < 80; j++) {
let newStar = document.createElement("div");
newStar.className = "star"
newStar.style.top = randomDistance(500, -100) + 'px'
newStar.style.left = randomDistance(1300, 300) + 'px'
stars.appendChild(newStar)
}
function randomDistance(max, min) {
let distance = Math.floor(Math.random() * (max - min + 1) + min)
return distance
}
var star = document.getElementsByClassName('star')
for (var i = 0, len = star.length; i < len; i++) {
star[i].style.animationDelay = i % 6 == 0 ? '0s' : i * 0.1 + 's'
}
})();