保证金顶部不使用<label>

Question

我试图通过为标签指定一个类'brtop'来轻推电子邮件标签并输入一点.

.brtop 只是增加了一个上边距.

似乎没有做任何事情,我做错了什么？

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/*  ^^CSS_RESET^^ --- vv CSSforsite vv */

form{
	width:500px;
	padding:1.5em;
	overflow:hidden;
	border:1px solid red;
}
fieldset{
	float:left;
	border:none;
	margin-left:1em;
}

.brtop{
margin-top:5px;
}

input{
}

<form name="messageform">
		<fieldset>
			<label for="username" >Name:</label><br/>
			<input type="text" name="username"/><br/>
			<label for="email"class="brtop">Email:</label><br/>
			<input type="text" name="email"/>
		</fieldset>
		<fieldset>
			<label>Message:</label><br/>
			<textarea name="message" cols="20" rows="4"></textarea>
		</fieldset>		
	</form>

Answer 1

添加display:inline-block到您的brtop规则.

.brtop {
    margin-top:5px;
    display:inline-block;
}

jsFiddle例子

由于您的标签显示为内联元素,因此上边距不会产生任何影响.

边距属性指定框的边距区域的宽度.'保证金'速记属性设定所有四边的保证金,而其他保证金属性仅设定各自的边.这些属性适用于所有元素,但垂直边距不会对未替换的内联元素产生任何影响.- W3

Answer 2

<label>是display: inline。如果您添加display: inline-block到.brtop它会尊重保证金。