期望效果

页面骨架

<div class="outter">
    <button>按钮1</button>
    <button>按钮2</button>
    <button>按钮3</button>
    <button>按钮4</button>
    <button>按钮5</button>
    <button>按钮6</button>
</div>
<button>外部的</button>