css transition opacity fade background

问题

I am doing a transition where it fades into transparent white, when a user is hovering an image.

My problem is that I need to change the color, that it fades to, to black. I have tried just simply adding background:black; to the class that contains the transition, but it does not work unfurtunately, it's still fading into white transparent.

The css code I am using is:

.hover:hover {
  opacity: 0.2;
}

.item-fade {
  background: black;
  opacity: 0.8;
  transition: opacity .25s ease-in-out;
  -moz-transition: opacity .25s ease-in-out;
  -webkit-transition: opacity .25s ease-in-out;
}

<p>Hover image, the white opacity needs to be black :/</p>
<img src="//placehold.it/100x100" class="hover item-fade" />

回答1:

Wrap your image into a SPAN element that has the background: black;

.imgHolder{
  display: inline-block;
  background: #000;
}
.item-fade{
  vertical-align: top;
  transition: opacity 0.3s;
  -webkit-transition: opacity 0.3s;
  opacity: 1;
}
.item-fade:hover{
  opacity: 0.2;
}

<span class="imgHolder">
   <img class="item-fade" src="http://placehold.it/100x100/cf5" />
</span>

回答2:

It's not fading to "black transparent" or "white transparent". It's just showing whatever color is "behind" the image, which is not the image's background color - that color is completely hidden by the image.

If you want to fade to black(ish), you'll need a black container around the image. Something like:

.ctr {
    margin: 0; 
    padding: 0;
    background-color: black;
    display: inline-block;
}

and

<div class="ctr"><img ... /></div>

回答3:

http://jsfiddle.net/6xJQq/13/

.container{
    display:inline-block;
    padding:5px;/*included padding to see background when img apacity is 100%*/
    background-color:black;
    opacity: 1;
}

.container:hover{
    background-color:red;
}
img{
    opacity: 1;
}
img:hover{
    opacity: 0.7;
}

.transition{
    transition: all .25s ease-in-out;
    -moz-transition: all .25s ease-in-out;
    -webkit-transition: all .25s 

}

回答4:

Please note that the problem is not white color. It is because it is being transparent.

When an element is made transparent, all of its child element's opacity; alpha filter in IE 6 7 etc, is changed to the new value.

So you cannot say that it is white!

You can place an element above it, and change that element's transparency to 1 while changing the image's transparency to .2 or what so ever you want to.

来源：https://stackoverflow.com/questions/21145621/css-transition-opacity-fade-background

标签

css

background

opacity

transition