如何对齐汉堡菜单项？

<div class="menu">
  <input type="checkbox" id="toggle">
  <label for="toggle" class="toggle-btn">
    <span></span>
    <span></span>
    <span></span>
  </label>
  <ul class="menu-items">
    <li><a href="#">菜单项1</a></li>
    <li><a href="#">菜单项2</a></li>
    <li><a href="#">菜单项3</a></li>
  </ul>
</div>

.menu {
  display: flex;
  align-items: center;
}

.toggle-btn {
  display: flex;
  flex-direction: column;
  justify-content: center;
  width: 30px;
  height: 20px;
  cursor: pointer;
}

.toggle-btn span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: #000;
  margin-bottom: 4px;
}

.menu-items {
  display: none;
  list-style: none;
  padding: 0;
  margin: 0;
}

#toggle:checked ~ .menu-items {
  display: block;
}