话不多，先看效果：

回归老本行，继续分享简单有趣的CSS创意特效，放松放松心情~

实现过程(完整源码在最后)：

1 老样子，定义基本样式：

*{

margin: 0;

padding: 0;

box-sizing: border-box;

font-family: 'fangsong';

}

body{

height: 100vh;

display: flex;

align-items: center;

justify-content: center;

background-color: rgb(0, 0, 0);

}

font-family: ‘fangsong’; 仿宋字体。

display: flex;

align-items: center;

justify-content: center; flex布局，让按钮在屏幕居中。

2.定义基本标签：

aurora

aurora

aurora

3个a标签就对应3个按钮，每个按钮里4个span就是环绕按钮的4条边。

且都有个公共的选择器 .item 和 只属于自己的选择器。

3.定义每个按钮的基本样式：

.item{

position: relative;

margin: 50px;

width: 300px;

height: 80px;

text-align: center;

line-height: 80px;

text-transform: uppercase;

text-decoration: none;

font-size: 35px;

letter-spacing: 5px;

color: aqua;

overflow: hidden;

-webkit-box-reflect: below 1px linear-gradient( transparent,rgba(6, 133, 133,0.3));

}

text-align: center;文字对齐方式。

line-height: 80px; 字行高。

text-transform: uppercase; 字母为大写。

text-decoration: none; 去掉a标签默认下划线。

letter-spacing: 5px; 每个字符间的距离。

overflow: hidden;溢出隐藏。

-webkit-box-reflect: below 1px linear-gradient( transparent,rgba(6, 133, 133,0.3)); 这个属性能实现倒影效果。

4. 鼠标经过按钮样式改变：

.item:hover{

background-color: aqua;

box-shadow:0 0 5px aqua,

0 0 75px aqua,

0 0 155px aqua;

color: black;

}

box-shadow:0 0 5px aqua,

0 0 75px aqua,

0 0 155px aqua; 阴影，写多行可以叠加更亮。

5.设置环绕按钮的4根线上面那条的样式：

.item span:nth-of-type(1){

position: absolute;

left: -100%;

width: 100%;

height: 3px;

background-image: linear-gradient(to left,aqua ,transparent);

animation: shang 1s linear infinite;

}

@keyframes shang{

0%{

left:-100%;

}

50%,100%{

left:100%;

}

}

position: absolute;

left: -100%; 定位在对应位置。

background-image: linear-gradient(to left,aqua ,transparent); 线性渐变颜色。

animation: shang 1s linear infinite; 动画属性，让它动起来。

5.以此类推，设置环绕按钮的其它3根样式：

.item span:nth-of-type(2){

position: absolute;

top: -100%;

right: 0;

width: 3px;

height: 100%;

background-image: linear-gradient(to top,aqua ,transparent);

animation: you 1s linear infinite;

animation-delay: 0.25s;

}

@keyframes you{

0%{

top:-100%;

}

50%,100%{

top:100%;

}

}

.item span:nth-of-type(3){

position: absolute;

right: -100%;

bottom: 0;

width: 100%;

height: 3px;

background-image: linear-gradient(to right,aqua ,transparent);

animation: xia 1s linear infinite;

animation-delay: 0.5s;

}

@keyframes xia{

0%{

right:-100%;

}

50%,100%{

right:100%;

}

}

.item span:nth-of-type(4){

position: absolute;

bottom: -100%;

left: 0;

width: 3px;

height: 100%;

background-image: linear-gradient(to bottom,aqua ,transparent);

animation: zuo 1s linear infinite;

animation-delay: 0.75s;

}

@keyframes zuo{

0%{

bottom:-100%;

}

50%,100%{

bottom:100%;

}

}

animation-delay: 0.75s; 动画延迟执行。每条线对应延迟一段时间，形成时间差，形成环绕效果。

6.给第一，第三个按钮设置其它颜色：

.item1{

filter: hue-rotate(100deg);

}

.item3{

filter: hue-rotate(250deg);

}

filter: hue-rotate(100deg); 用色相旋转，这样不管背景还是阴影颜色都变了。

完整代码：

Document

margin: 0;

padding: 0;

box-sizing: border-box;

font-family: 'fangsong';

}

body{

height: 100vh;

display: flex;

align-items: center;

justify-content: center;

background-color: rgb(0, 0, 0);

}

.item{

position: relative;

margin: 50px;

width: 300px;

height: 80px;

text-align: center;

line-height: 80px;

text-transform: uppercase;

text-decoration: none;

font-size: 35px;

letter-spacing: 5px;

color: aqua;

overflow: hidden;

-webkit-box-reflect: below 1px linear-gradient( transparent,rgba(6, 133, 133,0.3));

}

.item:hover{

background-color: aqua;

box-shadow:0 0 5px aqua,

0 0 75px aqua,

0 0 155px aqua;

color: black;

}

.item span:nth-of-type(1){

position: absolute;

left: -100%;

width: 100%;

height: 3px;

background-image: linear-gradient(to left,aqua ,transparent);

animation: shang 1s linear infinite;

}

@keyframes shang{

0%{

left:-100%;

}

50%,100%{

left:100%;

}

}

.item span:nth-of-type(2){

position: absolute;

top: -100%;

right: 0;

width: 3px;

height: 100%;

background-image: linear-gradient(to top,aqua ,transparent);

animation: you 1s linear infinite;

animation-delay: 0.25s;

}

@keyframes you{

0%{

top:-100%;

}

50%,100%{

top:100%;

}

}

.item span:nth-of-type(3){

position: absolute;

right: -100%;

bottom: 0;

width: 100%;

height: 3px;

background-image: linear-gradient(to right,aqua ,transparent);

animation: xia 1s linear infinite;

animation-delay: 0.5s;

}

@keyframes xia{

0%{

right:-100%;

}

50%,100%{

right:100%;

}

}

.item span:nth-of-type(4){

position: absolute;

bottom: -100%;

left: 0;

width: 3px;

height: 100%;

background-image: linear-gradient(to bottom,aqua ,transparent);

animation: zuo 1s linear infinite;

animation-delay: 0.75s;

}

@keyframes zuo{

0%{

bottom:-100%;

}

50%,100%{

bottom:100%;

}

}

.item1{

filter: hue-rotate(100deg);

}

.item3{

filter: hue-rotate(250deg);

}

aurora

aurora

aurora

总结：