borde del botón CSS
border: 2px solid #000;
Innovations
border: 2px solid #000;.placeholder-box {
position: relative;
display: block;
width: 300px;
min-height: 150px;
margin-top: 50px;
padding: 30px;
border: 1px solid #888;
border-radius: 10px;
box-sizing: border-box;
box-shadow: 0 0 8px 0 rgba(0,0,0,0.25);
}
.placeholder-box p {
text-align: center;
margin: 0 0 15px;
}
.placeholder-box ul {
margin: 0;
}
/* Button */
button {
display: block;
border: solid white;
border-width: 0 10px;
border-radius: 0;
background: green;
color: white;
font-size: 18px;
margin: -60px auto 15px;
padding: 15px;
}