.filepicker-ui button, 
.filepicker-ui input {
  border: 1px solid lightgray;
  font-size: 14px;
  padding: 4px 20px;
  height: 30px;
}  

.filepicker-ui button {
  border-right: none;
  border-top-left-radius: 5px;
  border-bottom-left-radius: 5px;
}

.filepicker-ui input {
  border-top-right-radius: 5px;
  border-bottom-right-radius: 5px;
}

.filepicker-preview > div {
  border: 1px solid lightgray;
  padding: 5px;
}