css - 按钮悬停效果down-top变色

Question

如何将此按钮的悬停效果从当前的自上而下反转为自下而上？

.btn-1 {
  position: relative;
  border-width: 2px;
  border-color: #4285f4;
  color: #4285f4;
  background-color: transparent;
}


.slide-btn, .slide-btn::after {
  -webkit-transition: all 0.3s;
	-moz-transition: all 0.3s;
  -o-transition: all 0.3s;
	transition: all 0.3s;
}

.slide-btn::before, .slide-btn::after {
  background: #4285f4;
  content: '';
  position: absolute;
  z-index: -1;
}

.btn-1::after {
  height: 0;
  left: 0;
  top: 0;
  width: 100%;
}

.btn-1:hover:after {
  height: 100%;
}

  <button class="btn-1 slide-btn">Button 1</button>

玩了很长时间，例如更改为 .btn-1::after { height: 100%; } 和 .btn-1::after { height:0; } ...这给了我向下的效果，但颜色相反。

Answer 1

在 .btn-1::after 中从上到下更改 https://jsfiddle.net/rp042h6j/

.btn-1::after {
  height: 0;
  left: 0;
  bottom: 0;
  width: 100%;
}