.form {
    display: inline-block;
    width: 100%;
    color: #444;
}
.form > input:not(.btn) {
        display: inline-block;
        float: left;
        width: 45%;
        margin-bottom: 30px;
        font-size: 18px;
        border: none;
        line-height: 36px;
        border-bottom: 2px solid grey;

}
    .form > input:not(.btn) + input:not(.btn) {
        margin-left: 10%;
    }
.form > textarea {
    width: 100%;
    min-height: 100px;
    max-height: 400px;
    border: none;
    line-height: 25px;
    font-size: 18px;
    border-bottom: 2px solid grey;
    resize: vertical;
    margin-bottom: 30px;

}
@media(max-width:1100px) {
    .form > input:not(.btn) { 
        width: 100%;
    }
    .form > input:not(.btn) + input:not(.btn) {
        margin-left: 0;
    }
}