Displaying a shadow ontop of pseudo element

Question

I am trying to achieve the following effect:

The code I have is as follows:

.box {
  background: #fff;
  width: 600px;
  height: 100px;
  position: relative;
  z-index: 999;
  box-shadow: 0px 2px 4px 0px rgba(0, 0, 0, 0.75);
}

.box::after {
  background: linear-gradient(to right, #00a1e4 25%, #ff9a00 25%, #ff9a00 50%, #00a525 50%, #00a525 75%, #8c449d 75%);
  position: absolute;
  content: "";
  height: 10px;
  right: 0;
  left: 0;
  bottom: -10px;
  z-index: 1;
}

<div class="box">
</div>

The pseudo element appears ontop of the box shadow in the above example, how can I get the shadow to appear over the top of the pseudo element?

Here is the example on codepen

Answer 1

You may redraw a shadow inside the pseudo :

.box {
  background: #fff;
  width:600px;
  height:100px;
  position: relative;
  z-index: 999;
  box-shadow: 0px 2px 4px 0px rgba(0, 0, 0, 0.75);
}

.box::after {
    background: linear-gradient(to right, 
      #00a1e4 25%, 
      #ff9a00 25%, 
      #ff9a00 50%, 
      #00a525 50%, 
      #00a525 75%, 
      #8c449d 75%);
    position: absolute;
    content: "";
    height: 10px;
    right: 0;
    left: 0;
    bottom: -10px;
    z-index: 1;
  box-shadow: inset 0 5px  4px -3px rgba(0, 0, 0, 0.75);
}

<div class="box">
  
</div>

you may also use mix-blend-mode :

.box {
  background: #fff;
  width:600px;
  height:100px;
  position: relative;
  z-index: 999;
  box-shadow: 0px 2px 4px 0px rgba(0, 0, 0, 0.75);
}

.box::after {
    background: linear-gradient(to right, 
      #00a1e4 25%, 
      #ff9a00 25%, 
      #ff9a00 50%, 
      #00a525 50%, 
      #00a525 75%, 
      #8c449d 75%);
    position: absolute;
    content: "";
    height: 10px;
    right: 0;
    left: 0;
    bottom: -10px;
    z-index: 1;
 mix-blend-mode:multiply;
}

<div class="box">
  
</div>