我试图在悬停时用css过渡缩略图,这样在悬停时,背景渐变就会淡入。转换没有工作,但如果我简单地将其更改为rgba()值,它就可以工作。不支持渐变吗?我也尝试使用图像,它也不会过渡图像。
我知道这是可能的,因为在另一篇文章中有人做到了,但我不知道具体是怎么做到的。这里有一些CSS工作:
#container div a {
-webkit-transition: background 0.2s linear;
-moz-transition: background 0.2s linear;
-o-transition: background 0.2s linear;
transition: background 0.2s linear;
position: absolute;
width: 200px;
height: 150px;
border: 1px #000 solid;
margin: 30px;
z-index: 2
}
#container div a:hover {
background: -webkit-gradient(radial, 100 75, 100, 100 75, 0, from(rgba(0, 0, 0, .7)), to(rgba(0, 0, 0, .4)))
}
基于你的问题中的css代码,我已经尝试代码如下,它为我工作(运行代码片段),请自己尝试:
#container div a {
display: inline-block;
margin-top: 10%;
padding: 1em 2em;
font-size: 2em;
color: #fff;
font-family: arial, sans-serif;
text-decoration: none;
border-radius: 0.3em;
position: relative;
background-color: #ccc;
background-image: linear-gradient(to top, #C0357E, #EE5840);
-webkit-backface-visibility: hidden;
z-index: 1;
}
#container div a:after {
position: absolute;
content: '';
top: 0;
left: 0;
width: 100%;
height: 100%;
border-radius: 0.3em;
background-image: linear-gradient(to top, #6d8aa0, #343436);
transition: opacity 0.5s ease-out;
z-index: 2;
opacity: 0;
}
#container div a:hover:after {
opacity: 1;
}
#container div a span {
position: relative;
z-index: 3;
}
<div id="container"><div><a href="#"><span>Press Me</span></a></div></div>
基于你的问题中的css代码,我已经尝试代码如下,它为我工作,请自己尝试:
#container div a {
display: inline-block;
margin-top: 10%;
padding: 1em 2em;
font-size: 2em;
color: #fff;
font-family: arial, sans-serif;
text-decoration: none;
border-radius: 0.3em;
position: relative;
background-color: #ccc;
background-image: linear-gradient(to top, #C0357E, #EE5840);
-webkit-backface-visibility: hidden;
z-index: 1;
}
#container div a:after {
position: absolute;
content: '';
top: 0;
left: 0;
width: 100%;
height: 100%;
border-radius: 0.3em;
background-image: linear-gradient(to top, #6d8aa0, #343436);
transition: opacity 0.5s ease-out;
z-index: 2;
opacity: 0;
}
#container div a:hover:after {
opacity: 1;
}
#container div a span {
position: relative;
z-index: 3;
}
这对你有用吗?
根据您的需要更改颜色:)
一种解决方法是转换背景位置,以产生渐变变化的效果:
http://sapphion.com/2011/10/css3-gradient-transition-with-background-position/
CSS3渐变过渡与背景位置
虽然你不能直接使用CSS的transition属性来动画渐变,但是你可以使用background-position属性来实现简单的渐变动画:
它的代码非常简单:
#DemoGradient{
background: -webkit-linear-gradient(#C7D3DC,#5B798E);
background: -moz-linear-gradient(#C7D3DC,#5B798E);
background: -o-linear-gradient(#C7D3DC,#5B798E);
background: linear-gradient(#C7D3DC,#5B798E);
-webkit-transition: background 1s ease-out;
-moz-transition: background 1s ease-out;
-o-transition: background 1s ease-out;
transition: background 1s ease-out;
background-size:1px 200px;
border-radius: 10px;
border: 1px solid #839DB0;
cursor:pointer;
width: 150px;
height: 100px;
}
#DemoGradient:Hover{
background-position:100px;
}
<div id="DemoGradient"></div>
不管怎样,这里有一个Sass mixin:
用法:
@include gradientAnimation(红色,蓝色,.6s);
混合:
@mixin gradientAnimation( $start, $end, $transTime ){
background-size: 100%;
background-image: linear-gradient($start, $end);
position: relative;
z-index: 100;
&:before {
background-image: linear-gradient($end, $start);
content: "";
display: block;
height: 100%;
position: absolute;
top: 0; left: 0;
opacity: 0;
width: 100%;
z-index: -100;
transition: opacity $transTime;
}
&:hover {
&:before {
opacity: 1;
}
}
}
摘自Dave Lunny在Medium上的这篇很棒的文章:https://medium.com/@dave_lunny/ animing-css -gradients-using-only-css-d2fd7671e759
一个更简洁的解决方案是设置背景色并使用蒙版图像。
#container div a {
background-color: blue;
transition: background 0.2s linear;
width: 200px;
height: 150px;
mask-image: radial-gradient(circle at 50% 50%, rgba(0, 0, 0, .7), rgba(0, 0, 0, .4));
}
#container div a:hover {
background-color: red;
}
在codepend上发现了一个很好的hack,可以修改不透明度属性,但通过利用伪元素实现从一个渐变到另一个渐变。他所做的就是设置:after,这样当你改变实际元素的不透明度时,:after元素就会显示出来,看起来就像渐变一样。我觉得分享一下会有用。
原始代码来源:http://codepen.io/sashtown/pen/DfdHh
.button {
display: inline-block;
margin-top: 10%;
padding: 1em 2em;
font-size: 2em;
color: #fff;
font-family: arial, sans-serif;
text-decoration: none;
border-radius: 0.3em;
position: relative;
background-color: #ccc;
background-image: linear-gradient(to top, #6d8aa0, #8ba2b4);
-webkit-backface-visibility: hidden;
z-index: 1;
}
.button:after {
position: absolute;
content: '';
top: 0;
left: 0;
width: 100%;
height: 100%;
border-radius: 0.3em;
background-image: linear-gradient(to top, #ca5f5e, #d68584);
transition: opacity 0.5s ease-out;
z-index: 2;
opacity: 0;
}
.button:hover:after {
opacity: 1;
}
.button span {
position: relative;
z-index: 3;
}
body {
text-align: center;
background: #ddd;
}
<a class="button" href="#"><span>BUTTON</span></a>
一种解决方案是使用背景位置来模拟梯度过渡。
几个月前,Twitter Bootstrap就使用了这个解决方案。
更新
http://codersblock.blogspot.fr/2013/12/gradient-animation-trick.html?showComment=1390287622614
这里有一个简单的例子:
链接状态
.btn {
font-family: "Helvetica Neue", Arial, sans-serif;
font-size: 12px;
font-weight: 300;
position: relative;
display: inline-block;
text-decoration: none;
color: #fff;
padding: 20px 40px;
background-image: -moz-linear-gradient(top, #50abdf, #1f78aa);
background-image: -webkit-gradient(linear, 0 0, 0 100%, from(#50abdf), to(#1f78aa));
background-image: -webkit-linear-gradient(top, #50abdf, #1f78aa);
background-image: -o-linear-gradient(top, #50abdf, #1f78aa);
background-image: linear-gradient(to bottom, #50abdf, #1f78aa);
background-repeat: repeat-x;
filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff50abdf', endColorstr='#ff1f78aa', GradientType=0);
background-repeat: repeat-y;
background-size: 100% 90px;
background-position: 0 -30px;
-webkit-transition: all 0.2s linear;
-moz-transition: all 0.2s linear;
-o-transition: all 0.2s linear;
transition: all 0.2s linear;
}
悬停状态
.btn:hover {
background-position: 0 0;
}