CSS 通过上滑动画过渡背景颜色

Transition background-color via slide up animation

提问by David Jones

I am trying to change the background-color of an element on hover by using CSS transitions. I want to do this by having it scroll up from the bottom. I can fade the background in using this, but I would like it to slide up:

我试图通过使用 CSS 转换来更改悬停时元素的背景颜色。我想通过让它从底部向上滚动来做到这一点。我可以使用它淡化背景，但我希望它向上滑动：

-webkit-transition: background-color 0.5s linear;
-moz-transition: background-color 0.5s linear;
-o-transition: background-color 0.5s linear;  
transition: background-color 0.5s linear;

One other thought, would it be better to scroll up a separate element with the background applied to it?

另一个想法是，向上滚动一个单独的元素并应用背景会更好吗？

回答by Sampson

In order to slide the background color upyou would need to use a background image, or a gradient of some sort, while gradually adjusting the background-position:

为了向上滑动背景颜色，您需要使用背景图像或某种渐变，同时逐渐调整background-position：

.box {
    width: 200px; height: 100px;
    background-size: 100% 200%;
    background-image: linear-gradient(to bottom, red 50%, black 50%);
    transition: background-position 1s;
}

.box:hover {
    background-position: 0 -100%;
}

You can see this demo here: http://jsfiddle.net/as5ZU/

你可以在这里看到这个演示：http: //jsfiddle.net/as5ZU/

回答by Temani Afif

An extension to @Sampson answer where I will consider more friendlyvalues easier to understand:

@Sampson 答案的扩展，我将考虑更容易理解的更友好的值：

.box {
  width: 100px;
  height: 100px;
  display:inline-block;
  background-size: 200% 200%;
  transition: background-position 1s;
}

.to-top{
  background-image: linear-gradient(to top, red 50%, black 0);
  background-position: top;
}

.to-top:hover {
  background-position: bottom;
}

.to-bottom{
  background-image: linear-gradient(to bottom, red 50%, black 0);
  background-position: bottom;
}

.to-bottom:hover {
  background-position: top;
}

.to-left{
  background-image: linear-gradient(to left, red 50%, black 0);
  background-position: left;
}

.to-left:hover {
  background-position: right;
}

.to-right{
  background-image: linear-gradient(to right, red 50%, black 0);
  background-position: right;
}

.to-right:hover {
  background-position: left;
}

<div class="box to-top"></div>

<div class="box to-bottom"></div>

<div class="box to-left"></div>

<div class="box to-right"></div>

Here is more fancy transitions:

这里有更多花哨的过渡：

.box {
  width: 100px;
  height: 100px;
  display:inline-block;
  transition:  1s;
}

.to-center{
  background: 
    linear-gradient(black,black) no-repeat,
    red;
  background-size: 100% 100%;
  background-position:center;
}

.to-center:hover {
  background-size: 0% 100%; /* Or 100% 0% */
}

.from-center{
  background: 
    linear-gradient(red,red) no-repeat,
    black;
  background-size: 0% 100%;  /* Or 100% 0% */
  background-position:center;
}

.from-center:hover {
  background-size: 100% 100%;
}

.diagonal-right{
  background-image:linear-gradient(to bottom right,red 49.5%,black 50%);
  background-size: 200% 200%;
  background-position:bottom right;
}

.diagonal-right:hover {
  background-position:top left;
}

.diagonal-left{
  background-image:linear-gradient(to bottom left,red 49.5%,black 50%);
  background-size: 200% 200%;
  background-position:bottom left;
}

.diagonal-left:hover {
  background-position:top right;
}

<div class="box to-center"></div>

<div class="box from-center"></div>

<div class="box diagonal-right"></div>


<div class="box diagonal-left"></div>

Related question to get more details about how background-positionworks combined with background-size: Using percentage values with background-position on a linear gradient

相关问题以获取有关如何background-position结合使用的更多详细信息background-size：在线性渐变上使用具有背景位置的百分比值