galaxy/Buttons/gagan-gv_rotten-fish-89.html

<button type="button" class="btn cube cube-hover">
  <div class="bg-top">
  <div class="bg-inner"></div>
  </div>
  <div class="bg-right">
  <div class="bg-inner"></div>
  </div>
  <div class="bg">
  <div class="bg-inner"></div>
  </div>
  <div class="text">Hover Me</div>
</button>
<style>
/* From Uiverse.io by gagan-gv - Tags: button */
.btn {
 display: block;
 padding: 0.7em 1em;
 background: transparent;
 outline: none;
 border: 0;
 color: #d4af37;
 letter-spacing: 0.1em;
 font-family: monospace;
 font-size: 17px;
 font-weight: bold;
 z-index: 1;
}

.cube {
 position: relative;
 transition: all 0.5s;
}

.cube .bg-top {
 position: absolute;
 height: 10px;
 background: #d4af37;
 bottom: 100%;
 left: 5px;
 right: -5px;
 transform: skew(-45deg, 0);
 margin: 0;
 transition: all 0.4s;
}

.cube .bg-top .bg-inner {
 bottom: 0;
}

.cube .bg {
 position: absolute;
 left: 0;
 bottom: 0;
 top: 0;
 right: 0;
 background: #d4af37;
 transition: all 0.4s;
}

.cube .bg-right {
 position: absolute;
 background: #d4af37;
 top: -5px;
 z-index: 0;
 bottom: 5px;
 width: 10px;
 left: 100%;
 transform: skew(0, -45deg);
 transition: all 0.4s;
}

.cube .bg-right .bg-inner {
 left: 0;
}

.cube .bg-inner {
 background: #28282d;
 position: absolute;
 left: 2px;
 right: 2px;
 top: 2px;
 bottom: 2px;
}

.cube .text {
 position: relative;
 transition: all 0.4s;
}

.cube:hover .bg-inner {
 background: #d4af37;
 transition: all 0.4s;
}

.cube:hover .text {
 color: #28282d;
 transition: all 0.4s;
}

.cube:hover .bg-right,
.cube:hover .bg,
.cube:hover .bg-top {
 background: #28282d;
}

.cube:active {
 z-index: 9999;
 animation: bounce .1s linear;
}

@keyframes bounce {
 50% {
  transform: scale(0.9);
 }
}
</style>