Custom CSS class applied to meta-bind-button does not work

[ariehen]

It looks like you want to target .mb-button-inner here:

Giving the button a cssclsss in the button builder:

You could give this a try:

/* Button 85 */
.button-85 .mb-button-inner {
  padding: 0.6em 2em;
  border: none;
  outline: none;
  color: rgb(255, 255, 255);
  background: #111;
  cursor: pointer;
  position: relative;
  z-index: 0;
  border-radius: 10px;
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
}

.button-85 .mb-button-inner:before {
  content: "";
  background: linear-gradient(
    45deg,
    #ff0000,
    #ff7300,
    #fffb00,
    #48ff00,
    #00ffd5,
    #002bff,
    #7a00ff,
    #ff00c8,
    #ff0000
  );
  position: absolute;
  top: -2px;
  left: -2px;
  background-size: 400%;
  z-index: -1;
  filter: blur(5px);
  -webkit-filter: blur(5px);
  width: calc(100% + 4px);
  height: calc(100% + 4px);
  animation: glowing-button-85 20s linear infinite;
  transition: opacity 0.3s ease-in-out;
  border-radius: 10px;
}

@keyframes glowing-button-85 {
  0% {
    background-position: 0 0;
  }
  50% {
    background-position: 400% 0;
  }
  100% {
    background-position: 0 0;
  }
}

.button-85 .mb-button-inner:after  {
  z-index: -1;
  content: "";
  position: absolute;
  width: 100%;
  height: 100%;
  background: #222;
  left: 0;
  top: 0;
  border-radius: 10px;
}

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