changing margin value using jQuery

I have below code if there is error msg. then the margin top of login form should be "0" and for the first error msg margin top should be "70px".

<span class="portlet-msg-error"> You have entered invalid data. Please try again. </span>

<span class="portlet-msg-error"> Authentication failed. Please try again.</span>

<div class="login-form" style开发者_高级运维="margin-top: 70px;"> Form Display here </div>

$('.login-form').css({'margin-top':'0px'}); // Login form
$('.portlet-msg-error:first').css({'margin-top':'70px'}); // Error Message

It may be marginTop, I forget if jQuery can accept the full name or if you have to camelCase it when there are hyphens

EDIT Just checked, margin-top seems to work

Try this:

if(error)
{
 $(".login-form").css("margin-top", "0");
 $(".portlet-msg-error:first").css("margin-top", "70px");
}

You can do this in CSS:

.login-form {
    margin-top: 0px;
}

.portlet-msg-error:first-child {
    margin-top: 70px;
}

The same in jQuery would be:

$('.login-form').css('margin-top', '0px');
$('.portlet-msg-error:first-child').css('margin-top', '70px');

So you see there is no real reason to use jQuery in this case.