<!DOCTYPE html>
<html>
  <body>
    <button class="btn">button</button>
    <input id="input-text" type="text" />
    <input id="input-radio" type="radio" />
    <input id="input-checkbox" type="checkbox" />
    <select id="select">
      <option value="0">0</option>
      <option value="1">1</option>
    </select>
    <select multiple id="multiple">
      <option value="0">0</option>
      <option value="1">1</option>
      <option value="2">2</option>
    </select>
    <button class="interactive">changing