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HTML： <ul class="tree" id="tree"> <li>Animals <ul> <li>Mammals <ul> <li>Cows</li> <li>Donkeys</li> <li>Dogs</li> <li>Tigers</li> </ul> </li> <li>Other 阅读全文
摘要：
HTML: container中有三个pane，点击按钮pane会消失 <div id="container"> <div class="pane"> <h3>Horse</h3> <p>The horse is one of two extant subspecies of Equus ferus 阅读全文