.btn-facebook {
    -webkit-transition: all 0.3s ease-in-out;
    -moz-transition: all 0.3s ease-in-out;
    -o-transitino: all 0.3s ease-in-out;
    transition: all 0.3s ease-in-out;
    height: 50px;
    width: 50px;
    border-radius: 100%;
    font-size: 20px;
    line-height: 37px;
}
.btn-facebook:hover,
.btn-facebook:focus {
    outline: none;
    color: #f4f5f7;
    background-color: #3b5998;
}
.btn-instagram {
    -webkit-transition: all 0.3s ease-in-out;
    -moz-transition: all 0.3s ease-in-out;
    -o-transitino: all 0.3s ease-in-out;
    transition: all 0.3s ease-in-out;
    height: 50px;
    width: 50px;
    border-radius: 100%;
    font-size: 20px;
    line-height: 37px;
}
.btn-instagram:hover,
.btn-instagram:focus {
    outline: none;
    color: #f4f5f7;
    background-color: #3f729b;
}
.btn-linkedin {
    -webkit-transition: all 0.3s ease-in-out;
    -moz-transition: all 0.3s ease-in-out;
    -o-transitino: all 0.3s ease-in-out;
    transition: all 0.3s ease-in-out;
    height: 50px;
    width: 50px;
    border-radius: 100%;
    font-size: 20px;
    line-height: 37px;
}
.btn-linkedin:hover,
.btn-linkedin:focus {
    outline: none;
    color: #f4f5f7;
    background-color: #007fb1;
}