#di-form {
    max-width: 600px;
}

#di-form input,
#di-form select {
    width: 100%;
    height: 45px;
    margin-bottom: 15px;
    padding: 10px;
}

#di-form button {
    background: #000;
    color: #fff;
    border: none;
    padding: 12px 20px;
    cursor: pointer;
}