ber">1</span> <span class="token operator">+</span> <span class="token string">'px'</span>

<span class="token comment">// good 缓存布局信息 相当于读写分离</span>
<span class="token keyword">var</span> curLeft <span class="token operator">=</span> div<span class="token punctuation">.</span>offsetLeft
<span class="token keyword">var</span> curTop <span class="token operator">=</span> div<span class="token punctuation">.</span>offsetTop
div<span class="token punctuation">.</span>style<span class=