Invert colored text related background

Question

I want to invert text color based on the background of the text, like in this image: .

So I've tried the following code, but it didn't work:

#warp,
#text,
#tri {
  position: absolute;
  top: 0;
  left: 0;
  width: 150px;
  height: 150px;
  z-index: 1;
}

#warp {
  background-color: orange;
}

#text {
  text-align: center;
  z-index: 3;
}

#text h1 {
  margin: 0;
  line-height: 150px;
  mix-blend-mode: difference;
}

#tri {
  background-color: black;
  clip-path: polygon(0 0, 0 100%, 99.8% 150px);
  -webkit-clip-path: polygon(0 0, 0 100%, 99.8% 150px);
  z-index: 2;
}

<div id="warp">
  <div id="text">
    <h1>TEXT</h1>
  </div>
  <div id="tri"></div>
</div>

I found some results about background-image & inverted text, but I don't know how to do it with DIVs.

Answer 1

You can avoid clip-path by using linear-gradient as background and the mix-blend-mode will work perfectly:

#text {
  width: 150px;
  height: 150px;
  z-index: 1;
}

#text {
  text-align: center;
  background: linear-gradient(to top right, black 50%, orange 51%);
}

#text h1 {
  margin: 0;
  line-height: 150px;
  mix-blend-mode: difference;
  color: #fff;
}

<div id="text">
  <h1>TEXT</h1>
</div>