.index {
position:fixed;
width:100%;
background:#000000;
height:100%;
}
#stars {
width:100%;
}
.star {
display:block;
width:5px;
height:5px;
border-radius:50%;
background:#FFF;
position:absolute;
transform-origin:100% 0;
animation:star-ani 4s linear infinite;
-webkit-animation:star-ani 5s linear infinite;
box-shadow:0 0 5px 5px rgba(255,255,255,.3);
opacity:0;
z-index:2;
}
.star:after {
content:'';
display:block;
top:0px;
left:4px;
border:0px solid #fff;
border-width:0px 90px 2px 90px;
border-color:transparent transparent transparent rgba(255,255,255,.3);
transform:rotate(-45deg) translate3d(1px,3px,0);
box-shadow:0 0 1px 0 rgba(255,255,255,.1);
transform-origin:0% 100%;
}
@keyframes star-ani {
0% {
opacity:0;
transform:scale(0) translate3d(0,0,0);
}
20% {
opacity:0.8;
transform:scale(0.2) translate3d(-100px,100px,0);
}
40% {
opacity:0.8;
transform:scale(0.4) translate3d(-200px,200px,0);
}
60% {
opacity:0.8;
transform:scale(0.6) translate3d(-300px,300px,0);
}
80% {
opacity:1;
transform:scale(1) translate3d(-350px,350px,0);
}
100% {
opacity:1;
transform:scale(1.2) translate3d(-400px,380px,0);
}
}// js随机生成流星
for (var j = 0; j < 20; j++) {
var newstar = document.createelement("div")
newstar.classname = "star"
newstar.style.top = randomdistance(500, -100) + 'px'
newstar.style.left = randomdistance(1980, 300) + 'px'
stars.appendchild(newstar)
}可改变j增加或减少生成的数量