<form>
  <p>Click on the text box and choose any option suggested by your browser.</p>

  <label for="name">Name</label>
  <input id="name" name="name" type="text" autocomplete="name" />

  <label for="email">Email Address</label>
  <input id="email" name="email" type="email" autocomplete="email" />

  <label for="country">Country</label>
  <input id="country" name="country" type="text" autocomplete="country-name" />
</form>

label {
  display: block;
  margin-top: 1em;
}

input:autofill {
  border: 3px solid darkorange;
}

input:-webkit-autofill {
  border: 3px solid darkorange;
}