字体名称有空格时如何使用jquery设置CSS字体系列

var font_family = 'Arial Black';
var $title_template = $('<h1>Title Text</h1>');
var $title;

console.log(font_family)
$title = $title_template.clone().css({'font-family': font_family});
$('body').append($title)

font_family = "'Arial Black'";
console.log(font_family);
$title = $title_template.clone().css({'font-family': font_family});
$('body').append($title)

font_family = '"Arial Black"';
console.log(font_family);
$title = $title_template.clone().css({'font-family': font_family});
$('body').append($title)

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<h1 style="font-family: 'Arial Black'">Title Text</h1>