fix bug

@@ -7,6 +7,7 @@
 var $ = require('yoho-jquery');
 
 var $nav = $('.category-nav'),
+    $search = $('#search-input'),
     $categoryContainer = $('.category-container'),
     $contents = $categoryContainer.children('.content'),
     $subLevelItem = $categoryContainer.find('.sub-level li'),
@@ -14,7 +15,13 @@ var $nav = $('.category-nav'),
 
 require('../common');
 
-$('#search-input').focus(function() {
+function resetHeight() {
+   var h = document.body.scrollHeight - $search.outerHeight() - $nav.outerHeight();
+   $contents.height(h);
+}
+resetHeight();
+
+$search.focus(function() {
     $(this).blur();
 });
 $nav.on('contextmenu', function() {

@@ -77,7 +77,10 @@
     }
 
     .content {
+        background: #f8f8f8;
         overflow: hidden;
+        position: relative;
+
         &.hide {
             display: none;
         }
@@ -87,7 +90,6 @@
         float: left;
         box-sizing: border-box;
         width: 45%;
-        background: #f8f8f8;
 
         > li {
             height: 89px;
@@ -108,10 +110,13 @@
     }
 
     .sub-level-container {
-        float: left;
+        position: absolute;
+        right: 0;
+        overflow-x: auto;
         box-sizing: border-box;
         background: #fff;
         width: 55%;
+        height: 100%;
     }
 
     .sub-level {