4-1 動畫舞台（HTML）
<div id="stage">
<div id="sun"></div>
<div id="ground"></div>
<div id="person">
<div class="head"></div>
<div class="body"></div>
<div class="leg left"></div>
<div class="leg right"></div>
<div class="arm left"></div>
<div class="arm right"></div>
</div>
</div>
<button id="btnToggle">暫停</button>