input[type=file]::file-selector-button {
  background: #1c7cbb;
  color: white;
  border: 3px solid #333;
  border-radius: 5px;
  padding: 0.5em;
  width: 10em;
}

input[type=file]::file-selector-button:hover {
  background: linear-gradient(to right, orange , yellow, green, cyan, blue, violet);
}
  

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