<label for="recipients">Where should we send the receipt?</label>
<input id="recipients" name="recipients" type="email" multiple />

<label for="shakes">Which shakes would you like to order?</label>
<select id="shakes" name="shakes" multiple>
  <option>Vanilla Shake</option>
  <option>Strawberry Shake</option>
  <option>Chocolate Shake</option>
</select>

<label for="payment">How would you like to pay?</label>
<select id="payment" name="payment">
  <option>Credit card</option>
  <option>Bank Transfer</option>
</select>

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

input,
select {
  width: 100%;
}

input:invalid {
  background-color: lightpink;
}