button {
 position: relative;
 height: 50px;
 padding: 0 30px;
 border: 2px solid #000;
 background: #e8e8e8;
 user-select: none;
 white-space: nowrap;
 transition: all .05s linear;
 font-family: inherit;
}

button:before, button:after {
 content: "";
 position: absolute;
 background: #e8e8e8;
 transition: all .2s linear;
}

button:before {
 width: calc(100% + 6px);
 height: calc(100% - 16px);
 top: 8px;
 left: -3px;
}

button:after {
 width: calc(100% - 16px);
 height: calc(100% + 6px);
 top: -3px;
 left: 8px;
}

button:hover {
 cursor: crosshair;
}

button:active {
 transform: scale(0.95);
}

button:hover:before {
 height: calc(100% - 32px);
 top: 16px;
}

button:hover:after {
 width: calc(100% - 32px);
 left: 16px;
}

button span {
 font-size: 15px;
 z-index: 3;
 position: relative;
 font-weight: 600;
}