css
.btn {
position: relative;
display: block;
margin: 0 25px;
margin-top: 100px;
padding: 20px 0;
width: 250px;
border: none;
box-sizing: content-box;
background-color: #2c3e50;
color: white;
text-align: center;
text-transform: uppercase;
font: inherit;
line-height: 20px;
box-shadow:
inset 0px 5px 0px 0px #16a085,
inset 0px -5px 0px 0px #16a085,
0px 20px 0px -10px #2980b9,
0px 40px 0px -20px #3498db,
0px -20px 0px -10px #c0392b,
0px -40px 0px -20px #e74c3c;
}
.btn::before,
.btn::after {
position: absolute;
content: '';
background-color: #2ecc71;
width: 50%;
height: 5px;
}
.btn::before {top: 0; left: 0;}
.btn::after {bottom: 0; right: 0;}