style.css

.app {
  font-family: 'Segoe UI', Avenir, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.dropzone {
  display: none;
}

.interface {
  position: absolute;
  top: 0;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.textUploader {
  position: relative;
  display: none;
}

.textUploader--visible {
  display: flex;
  z-index: 99999;
}

input {
  height: 48px;
  width: 280px;
  border: 1px solid #c0c0c0;
  border-radius: 4px;
  box-sizing: border-box;
  padding: 16px;
}

.label {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 16px;
  display: flex;
  align-items: center;
  pointer-events: none;
}

input, .label .text {
  font-size: 16px;
}

.label .text {
  transition: all 0.15s ease-out;
  color: grey;
}

input:focus {
  outline: none;
  border: 2px solid blue;
}

input:focus + .label .text,
:not(input[value=""]) + .label .text {
  font-size: 12px;
  transform: translate(0, -150%);
  background-color: white;
  padding-left: 4px;
  padding-right: 4px;
}

input:focus + .label .text {
  color: blue;
}