body {
    background-color: #f5f5f5;
    text-align: center;
    padding-top: 100px;
}

form {
    width: 100%;
    max-width: 330px;
    padding: 15px;
    margin: auto;
}

.form-group {
    margin-bottom: 0px;
}

.form-control {
    position: relative;
    box-sizing: border-box;
    height: auto;
    padding: 10px;
    font-size: 16px;
}

form input {
    margin-bottom: 10px;
}

#_username {
    margin-bottom: -1px;
    border-bottom-right-radius: 0;
    border-bottom-left-radius: 0;
}
#_password {
    border-top-left-radius: 0;
    border-top-right-radius: 0;
}
#login {
    margin-top: 10px;
}