如果我设置firstGroup为float: right，我会得到两列，第一组在右侧，如预期的那样。但是，如果我将其设置为float: left，我只会将以下元素卡在第一个元素的底部！
注意：我需要一直支持到 IE7，所以没有column-count.
这是我的页面的一个大大简化的版本（我只留下了相关的块元素，只给出了几个示例项目）：
<!DOCTYPE html>
<html>
<head>
<title>Take</title>
<style type="text/css">
.group
{
margin-bottom: 20px;
width: 50%;
min-width: 530px;
}
.group > .group
{
margin-bottom: 0px;
}
.group > .label
{
display: block;
width: 510px;
padding: 5px;
border: 1px solid black;
}
.firstGroup
{
float: left;
}
.item
{
display: block;
width: 510px;
padding: 5px;
border: 1px solid black;
}
.item .label
{
display: block;
float: left;
width: 200px;
height: 20px;
}
.header textarea
{
display: block;
}
.header
{
margin-bottom: 20px;
}
</style>
</head>
<body>
<div class="page">
<div class="main">
<h2>Title</h2>
<form>
<div class="header">
Notes :
<textarea name="Notes"></textarea>
</div>
<div class="group firstGroup">
<span class="label" style="background-color: #005588; color: white;">List 1</span>
<div class="group">
<span class="label" style="background-color: #999999; color: #000000;">Sub List 1</span>
<span class="item" style="background-color: #339933; color: #000000;">
<span class="label">Item 1</span>
<span class="options">
<span class="option"><input name="item[0].itemResultID" type="radio" value="0" checked="checked" />N/A</span>
<span class="option"><input name="item[0].itemResultID" type="radio" value="1" />Yes</span>
<span class="option"><input name="item[0].itemResultID" type="radio" value="2" />No</span>
</span>
<span class="notes"><input type="text" name="item[0].TestNotes" value="" /></span>
</span>
<span class="item" style="background-color: #339933; color: #000000;">
<span class="label">Item 2</span>
<span class="options">
<span class="option"><input name="item[1].itemResultID" type="radio" value="0" checked="checked" />N/A</span>
<span class="option"><input name="item[1].itemResultID" type="radio" value="1" />Yes</span>
<span class="option"><input name="item[1].itemResultID" type="radio" value="2" />No</span>
</span>
<span class="notes"><input type="text" name="item[1].TestNotes" value="" /></span>
</span>
<span class="item" style="background-color: #339933; color: #000000;">
<span class="label">Item 3</span>
<span class="options">
<span class="option"><input name="item[2].itemResultID" type="radio" value="0" checked="checked" />N/A</span>
<span class="option"><input name="item[2].itemResultID" type="radio" value="1" />Yes</span>
<span class="option"><input name="item[2].itemResultID" type="radio" value="2" />No</span>
</span>
<span class="notes"><input type="text" name="item[2].TestNotes" value="" /></span>
</span>
</div>
<div class="group">
<span class="label" style="background-color: #999999; color: #000000;">Sub List 2</span>
<span class="item" style="background-color: yellow; color: #000000;">
<span class="label">Item 1</span>
<span class="options">
<span class="option"><input name="item[3].itemResultID" type="radio" value="0" checked="checked" />N/A</span>
<span class="option"><input name="item[3].itemResultID" type="radio" value="1" />Yes</span>
<span class="option"><input name="item[3].itemResultID" type="radio" value="2" />No</span>
</span>
<span class="notes"><input type="text" name="item[3].TestNotes" value="" /></span>
</span>
</div>
</div>
<div class="group">
<span class="label" style="background-color: red; color: white;">List 2</span>
<span class="item" style="background-color: #339933; color: #000000;">
<span class="label">Item 1</span>
<span class="options">
<span class="option"><input name="item[4].itemResultID" type="radio" value="0" checked="checked" />N/A</span>
<span class="option"><input name="item[4].itemResultID" type="radio" value="1" />Yes</span>
<span class="option"><input name="item[4].itemResultID" type="radio" value="2" />No</span>
</span>
<span class="notes"><input type="text" name="item[4].TestNotes" value="" /></span>
</span>
<span class="item" style="background-color: #339933; color: #000000;">
<span class="label">Item 2</span>
<span class="options">
<span class="option"><input name="item[5].itemResultID" type="radio" value="0" checked="checked" />N/A</span>
<span class="option"><input name="item[5].itemResultID" type="radio" value="1" />Yes</span>
<span class="option"><input name="item[5].itemResultID" type="radio" value="2" />No</span>
</span>
<span class="notes"><input type="text" name="item[5].TestNotes" value="" /></span>
</span>
</div>
<input type="submit" value="Submit" />
</form>
</div>
</div>
</body>
</html>
我已经在 FF 8 和 IE 9 中进行了测试，两者的行为相同。