

https://github.com/comehope/front-end-daily-challenges/tree/master/016-colorful-gradient-animated-border
定义 dom,一个容器中包含一些文字:
<div class="box"> you are my<br> FAVORITE </div>
居中显示:
html,
body,
.box {
height: 100%;
display: flex;
align-items: center;
justify-content: center;
}设置页面背景色:
body {
background: #222;
}设置容器和文字样式:
.box {
color: white;
font-size: 2.5em;
width: 10em;
height: 5em;
background: #111;
font-family: sans-serif;
line-height: 1.5em;
text-align: center;
border-radius: 0.2em;
}用伪元素增加一个背板:
.box {
position: relative;
}
.box::after {
content: '';
position: absolute;
width: 102%;
height: 104%;
background-color: orange;
z-index: -1;
border-radius: 0.2em;
}把背板设置为渐变色的:
.box::after {
/*background-color: orange;*/
background-image: linear-gradient(60deg, aquamarine, cornflowerblue, goldenrod, hotpink, salmon, lightgreen, sandybrown, violet);
}为背板设置动画效果:
.box::after {
background-size: 300%, 300%;
animation: animate_bg 5s ease infinite alternate;
}
@keyframes animate_bg {
0% {
background-position: 0%, 50%;
}
50% {
background-position: 100%, 50%;
}
100% {
background-position: 0%, 50%;
}
}最后,再为文字增加变色效果:
.box {
animation: animate_text 2s linear infinite alternate;
}
@keyframes animate_text {
from {
color: lime;
}
to {
color: yellow;
}
}大功告成!
