Jquery Safari的基础5 TopBar搜索

我在狩猎中遇到了一些问题

当我点击搜索图标时，我们有下拉搜索输入，当我开始写东西时，顶部的栏被打破

但当顶部的栏打开，我们在搜索中写下一些东西时，一切都正常

我不知道为什么会这样，但在Chrome中一切都很好

<nav class="top-bar" data-topbar role="navigation">
            <ul class="title-area">
                <li class="name">
                    <a href="#"><img src="img/logo.png" alt="logobrand"/></a>
                </li>

                <!-- Remove the class "menu-icon" to get rid of menu icon. Take out "Menu" to just have icon alone -->
                <li class="toggle-topbar menu-icon"><a href="#"><span></span></a></li>

                <li class="mob_search">
                    <span class="search"></span>

                    <div class="drop_search">
                        <div class=" collapse">
                            <div class="large-12 small-12 columns">
                                <form action="">
                                <button type="submit" class="search"></button>
                                <input type="search" placeholder="what are you looking for?">
                                </form>
                            </div>
                        </div>
                    </div>
                </li>

            </ul>

            <section class="top-bar-section">
                <!-- Right Nav Section -->
                <ul class="right">
                    <li class="divider"></li> .....

$(".mob_search > .search").click(function(){
   $(".drop_search").toggle("slow");
});`