.custom-file {
    display: inline-block;
    margin-bottom: 0;
}

.custom-file, .custom-file-input {
    position: relative;
    width: 100%;
    height: calc(32px + 10px + 2px);
}

.custom-file-input {
    z-index: 2;
    margin: 0;
    overflow: hidden;
    opacity: 0;
}

.custom-file-label:after {
    bottom: 0;
    z-index: 3;
    display: block;
    content: "SCEGLI";
    background-color: #000;
    border-left: inherit;
    border-radius: 0 7px 7px 0;
    color: #fff;
    font-size: 14px;
}

.custom-file-label {
    left: 0;
    z-index: 1;
    height: calc(32px + 10px + 2px);
    overflow: hidden;
    font-weight: 400;
    background-color: #fff;
    border: 1px solid #dee2e6;
    border-radius: 7px;
    margin-top: 0px;
    color: #495057;
    font-size: 15px;
}

.custom-file-label, .custom-file-label:after {
    position: absolute;
    top: 0;
    right: 0;
    padding: 0.375rem 0.75rem;
    line-height: 32px;
}