<div class="input-container">
  <input
    type="text"
    id="fname"
    name="fname"
    value=""
    aria-labelledby="label-fname"
  />
  <label class="label" for="fname" id="label-fname">
    <div class="text">First Name</div>
  </label>
</div>

.input-container {
  position: relative;
}

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-family: 'Segoe UI';
  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;
}

const input = document.getElementById('fname');

input.addEventListener('input', () => {
  input.setAttribute('value', input.value);
});