change input file style code example

Example 1: input type file custom css

.custom-file-input::-webkit-file-upload-button {
  visibility: hidden;
}
.custom-file-input::before {
  content: 'Select some files';
  display: inline-block;
  background: linear-gradient(top, #f9f9f9, #e3e3e3);
  border: 1px solid #999;
  border-radius: 3px;
  padding: 5px 8px;
  outline: none;
  white-space: nowrap;
  -webkit-user-select: none;
  cursor: pointer;
  text-shadow: 1px 1px #fff;
  font-weight: 700;
  font-size: 10pt;
}
.custom-file-input:hover::before {
  border-color: black;
}
.custom-file-input:active::before {
  background: -webkit-linear-gradient(top, #e3e3e3, #f9f9f9);
}

Example 2: target button of fileinput css

.upload-btn {

    display: block;
    text-align: center;
    margin: 20px auto 20px;
    width: 50%;
    height: 30px;
    background-color: #fcff7f;
    line-height: 30px;

    }

.upload-btn:hover {
    background-color: #c39d5a;
    color: white;
    cursor: pointer;
    }