如何在css3中将类调用到另一个类？

Question

当我悬停已经拥有自己过渡的外部div框（父级）时，我想创建一个会触发我的按钮转换的效果。这可以用css完成还是需要一些javascript？

我的例子：

.box {
	height: 300px;
	width: 300px;
	background: #eeeeee;	
	float: left;
	margin: 50px;
	-webkit-transition: All 0.5s ease;
	-moz-transition: All 0.5s ease;
	-o-transition: All 0.5s ease;
	-ms-transition: All 0.5s ease;
	transition: All 0.5s ease;
}
.box:hover {
	height: 350px;
}

#box_pic1 {
	background: url(http://nicholsd.com/_Media/image-15_med.png);
	background-repeat: no-repeat;
	background-position: relative;
	height: 196px;
	width: 262px;
	margin: 0 auto;
	margin-top: 20px;
}

.btn_ani {
	font-size: 13px;
	text-align: center;
	color: #ffffff;
	opacity: 0.5;
	width: 150px;
	background: #99745c;
	border:1px solid #99745c;
	line-height: 35px;
	transition: opacity 0.5s;
	-webkit-transition: all ease 0.5s;
	-moz-transition: all ease 0.5s;
	-o-transition: all ease 0.5s;
	-ms-transition: all ease 0.5s;
	transition: all ease 0.5s;		
	position: absolute;	
	margin-left: 56px;
}

.btn_ani:hover {
	background: #ffffff;
	color: #99745c;
    opacity: 1;
	-webkit-transition: all ease 0.7s;
	-moz-transition: all ease 0.7s;
	-o-transition: all ease 0.7s;
	-ms-transition: all ease 0.7s;
	transition: all ease 0.5s;	
	border:1px solid #99745c;
	margin-top: 80px;
}

<div class="box">				
	<a href="www.google.com">
		<div id="box_pic1">
			<div class="btn_ani">View</div>
		</div>
	</a>			
</div>

Answer 1

可以使用CSS完成。您只需将:hover状态移至父.box，将目标移至.box:hover .btn_ani。

在这种情况下，元素可以有自己的transition值。

＆＃13;

＆＃13;

.box {
  height: 300px;
  width: 300px;
  background: #eeeeee;	
  float: left;
  margin: 50px;
  -webkit-transition: all 0.5s ease;
  -moz-transition: all 0.5s ease;
  -o-transition: all 0.5s ease;
  -ms-transition: all 0.5s ease;
  transition: all 0.5s ease;
}
.box:hover {
  height: 350px;
}

#box_pic1 {
  background: url(http://nicholsd.com/_Media/image-15_med.png);
  background-repeat: no-repeat;
  background-position: relative;
  height: 196px;
  width: 262px;
  margin: 0 auto;
  margin-top: 20px;
}

.btn_ani {
  font-size: 13px;
  text-align: center;
  color: #ffffff;
  opacity: 0.5;
  width: 150px;
  background: #99745c;
  border:1px solid #99745c;
  line-height: 35px;
  transition: opacity 0.5s;
  
  /* different transition from the parent */
  -webkit-transition: all ease 0.7s;
  -moz-transition: all ease 0.7s;
  -o-transition: all ease 0.7s;
  -ms-transition: all ease 0.7s;
  transition: all ease 0.7s;
  
  position: absolute;	
  margin-left: 56px;
}

.box:hover .btn_ani {
  background: #ffffff;
  color: #99745c;
  opacity: 1;	
  border:1px solid #99745c;
  margin-top: 80px;
}

＆＃13;

<div class="box">				
  <a href="www.google.com">
    <div id="box_pic1">
      <div class="btn_ani">View</div>
    </div>
  </a>			
</div>

＆＃13;

＆＃13;

＆＃13;

Answer 2

如果你想想尝试一些jQuery，你可以使用这样的解决方案：

$('.box').hover(function(){
    $('.btn_ani').toggleClass('margin');
});

使用css：

.margin{
    margin-top:80px;
}

and here is an example!