.searchForm-box {
    position: relative;
}
    .searchForm .txtBox {
        width: 100%;
        padding: .8rem;
        padding-right: 70px;
    }
    .searchForm-btn {
        background-color: #101010;
        position: absolute;
        top:0; right:0; bottom:0;
        color: #fff;
        width: 50px;
    }
    .searchForm-btn:hover {
        background-color: #c03c3f;
    }