为什么这个背景图片不显示在jsfiddle上？

Question

我遇到了出现背景图片的问题。看看我的jsfiddle并告诉我我错过了什么？

<div id="postcard-container">
<div id="postcard">
    <div id="postcard-title">
        <h1>Milkweed</h1>

    </div>
    <div id="postcard-sub">What is Milk weed? Sign up to Find out</div>
    <div id="postcard-email">
        <hr>Email capture situation</div>
    <div id="postcard-social"></div>
</div>
</div>

Answer 1

更改

background-image: url(...) no-repeat center center fixed;

到

background: url(...) no-repeat center center fixed;