利用css3的clip和keyframes帧动画，实现的类似于小时候看的黑白电视，信号不好的抖动效果的404文字抖动代码。代码如下：
<h2 data-text="404">404</h2>
<style type="text/css">
body{
text-align: center;
}
h2{
font-size: 70px;
position: relative;
letter-spacing: 1px;
z-index: 3;
display: inline-block;
}
h2:before {
content: attr(data-text);
position: absolute;
left: -2px;
text-shadow: 1px 0 blue;
top: 0;
color: #000;
background: #f6f8f9;
overflow: hidden;
clip: rect(0, 900px, 0, 0);
width: 100%;
animation: noise-anim-2-3f562eed 3s infinite linear alternate-reverse;
}
h2:after {
content: attr(data-text);
position: absolute;
left: 2px;
text-shadow: -1px 0 red;
top: 0;
color: #000;
background: #f6f8f9;
overflow: hidden;
clip: rect(0, 900px, 0, 0);
width: 100%;
animation: noise-anim-3f562eed 2s infinite linear alternate-reverse;
}
@keyframes noise-anim-2-3f562eed {
0% {
clip: rect(20px, 9999px, 7px, 0);
}
5% {
clip: rect(51px, 9999px, 73px, 0);
}
10% {
clip: rect(33px, 9999px, 21px, 0);
}
15% {
clip: rect(60px, 9999px, 48px, 0);
}
20% {
clip: rect(86px, 9999px, 48px, 0);
}
25% {
clip: rect(32px, 9999px, 50px, 0);
}
30% {
clip: rect(59px, 9999px, 50px, 0);
}
35% {
clip: rect(80px, 9999px, 96px, 0);
}
40% {
clip: rect(7px, 9999px, 39px, 0);
}
45% {
clip: rect(62px, 9999px, 90px, 0);
}
50% {
clip: rect(85px, 9999px, 84px, 0);
}
55% {
clip: rect(89px, 9999px, 51px, 0);
}
60% {
clip: rect(88px, 9999px, 50px, 0);
}
65% {
clip: rect(8px, 9999px, 82px, 0);
}
70% {
clip: rect(80px, 9999px, 23px, 0);
}
75% {
clip: rect(22px, 9999px, 52px, 0);
}
80% {
clip: rect(96px, 9999px, 44px, 0);
}
85% {
clip: rect(84px, 9999px, 27px, 0);
}
90% {
clip: rect(32px, 9999px, 71px, 0);
}
95% {
clip: rect(85px, 9999px, 35px, 0);
}
100% {
clip: rect(24px, 9999px, 23px, 0);
}
}
@keyframes noise-anim-3f562eed {
0% {
clip: rect(77px, 9999px, 51px, 0);
}
5% {
clip: rect(25px, 9999px, 30px, 0);
}
10% {
clip: rect(70px, 9999px, 75px, 0);
}
15% {
clip: rect(94px, 9999px, 96px, 0);
}
20% {
clip: rect(24px, 9999px, 11px, 0);
}
25% {
clip: rect(12px, 9999px, 53px, 0);
}
30% {
clip: rect(79px, 9999px, 54px, 0);
}
35% {
clip: rect(70px, 9999px, 93px, 0);
}
40% {
clip: rect(73px, 9999px, 86px, 0);
}
45% {
clip: rect(100px, 9999px, 96px, 0);
}
50% {
clip: rect(5px, 9999px, 68px, 0);
}
55% {
clip: rect(6px, 9999px, 16px, 0);
}
60% {
clip: rect(4px, 9999px, 60px, 0);
}
65% {
clip: rect(86px, 9999px, 74px, 0);
}
70% {
clip: rect(6px, 9999px, 53px, 0);
}
75% {
clip: rect(41px, 9999px, 35px, 0);
}
80% {
clip: rect(70px, 9999px, 60px, 0);
}
85% {
clip: rect(52px, 9999px, 66px, 0);
}
90% {
clip: rect(18px, 9999px, 16px, 0);
}
95% {
clip: rect(71px, 9999px, 80px, 0);
}
100% {
clip: rect(69px, 9999px, 51px, 0);
}
}
</style>