用CSS在悬停时制作圆形边框的动画

Question

我正在尝试创建一个按钮悬停动画，其中为边界线设置了动画。有人知道是否可以用css制作圆角动画，或者我需要创建一个svg动画吗？参见下面的代码笔：

请参阅CodePen上Anton Lipovskoy(@Lipovskoy(的笔按钮边框悬停效果。

@import url(https://fonts.googleapis.com/css?family=PT+Sans);
*, *:after, *:before {
-webkit-box-sizing: border-box;
-moz-box-sizing: border-box;
box-sizing: border-box;
}
body{
font-family: 'PT Sans', sans-serif;
display: table;
width: 100%;
background: #004b60;
}
.container{
display: table-cell;
vertical-align: middle;
text-align: center;
height: 100vh;
}
button{
display: inline-block;
position: relative;
background: none;
border: none;
color: #fff;
font-size: 16px;
cursor: pointer;
margin: 10px 20px;
background: rgba(0, 210, 195, 1);
border-radius: 0.175rem;
-webkit-transition: all .5s ease-out;
-moz-transition: all .5s ease-out;
-o-transition: all .5s ease-out;
transition: all .5s ease-out;
}
span{
display: block;
padding: 15px 20px;
}
button::before, button::after{
content:"";
width: 0;
height: 1px;
position: absolute;
background: rgba(0, 210, 195, 1);
border-radius: 0.175rem;
transition: all 0.2s ease-out;
}
span::before, span::after{
content:"";
width:1px;
height:0;
position: absolute;
background: rgba(0, 210, 195, 1);
border-radius: 0.175rem;
transition: all 0.2s ease-out;
}
button:hover::before, button:hover::after{
width: 100%;
}
button:hover{
background: rgba(0, 210, 195, 0.1);
color:rgba(0, 210, 195, 1);
}
button:hover span::before, button:hover span::after{
height: 100%;
}
/*----- button 4 -----*/
.btn-4::after{
right:0;
bottom: 0;
transition-duration: 0.4s;
}
.btn-4 span::after{
right:0;
bottom: 0;
transition-duration: 0.2s;
}
.btn-4::before{
left: 0;
top: 0;
transition-duration: 0.4s;
}
.btn-4 span::before{
left: 0;
top: 0;
transition-duration: 0.2s;
}

<div class="container">
<button class="btn-4"><span>Hover Me</span></button>
</div>

Answer 1

我试着让它与border-radius、width、height一起工作。您可以根据输入更改其边界半径。也许它会帮助你得到你想要的。

@import url(https://fonts.googleapis.com/css?family=PT+Sans);
*, *:after, *:before {
-webkit-box-sizing: border-box;
-moz-box-sizing: border-box;
box-sizing: border-box;
}
body{
font-family: 'PT Sans', sans-serif;
display: table;
width: 100%;
background: #004b60;
}
.container{
display: table-cell;
vertical-align: middle;
text-align: center;
height: 100vh;
}
button{
display: inline-block;
position: relative;
background: none;
border: none;
color: #fff;
font-size: 16px;
cursor: pointer;
margin: 10px 20px;
background: rgba(0, 210, 195, 1);
border-radius: 15px;
-webkit-transition: all .5s ease-out;
-moz-transition: all .5s ease-out;
-o-transition: all .5s ease-out;
transition: all .5s ease-out;
}
span{
display: block;
padding: 15px 20px;
}
button::before{  
border-top:1px solid rgba(0,210, 195, 1);
border-radius:0px;
border-top-left-radius:0px;
border-top-right-radius:0;

border-bottom-right-radius:0;
border-bottom-left-radius:0;
}
button::after{  
border-bottom:1px solid rgba(0,210, 195, 1);
border-radius:0px;
border-bottom-right-radius:0;
border-bottom-left-radius:0;
border-top-left-radius:0;
border-top-right-radius:0;

}
button::before, button::after{
content:"";
width: 0;
height: 0;
position: absolute;
/*background: rgba(0, 210, 195, 1);*/
border-radius: 15px;
transition: all 0.2s ease-out;
}
span::before {
border-left:1px solid rgba(0,210, 195, 1);
border-radius:0;

border-top-left-radius:0px;
border-top-right-radius:0;

border-bottom-right-radius:0;
border-bottom-left-radius:0px;
}
span::after {
border-right:1px solid rgba(0,210, 195, 1);
border-radius:0;

border-top-left-radius:0;
border-top-right-radius:0px;

border-bottom-right-radius:0px;
border-bottom-left-radius:0;
}
span::before, span::after{
content:"";
width:0;
height:0;
position: absolute;
/*background: rgba(0, 210, 195, 1);*/
border-radius: 15px;
transition: all 0.2s ease-out;
}
button:hover::before, button:hover::after{
width: 100%;
height:35px;
}
button:hover::before{
left: 0;
border-top-left-radius:15px;
}
button:hover::after{
right: 0;
border-bottom-right-radius:15px;
}
button:hover{
background: rgba(0, 210, 195, 0.1);
color:rgba(0, 210, 195, 1);
}
button:hover span::before, button:hover span::after{
height: 100%;
width:55px;
}
button:hover span::before{
top:0;
border-bottom-left-radius:15px;
}
button:hover span::after {
bottom:0;

border-top-right-radius:15px;
}
/*----- button 4 -----*/
.btn-4::after{
right:10px;
bottom: 0;
transition-duration: 0.4s;
}
.btn-4 span::after{
right:0;
bottom: 10px;
transition-duration: 0.2s;
}
.btn-4::before{
left: 10px;
top: 0;
transition-duration: 0.4s;

}
.btn-4 span::before{
left: 0;
top: 10px;
transition-duration: 0.2s;

}

<div class="container">
<button class="btn-4"><span>Hover Me</span></button>
</div>

你也可以在这里测试

我仍然相信SVG是最有效的方法。