你的代碼可能打錯了??

*{padding:0; margin:0;}
html, body{ height:100%; overflow:hidden;}
#container,.sections,.section{height:100%;}
#section0,#section1,#section2,#section3{background-color:#000; background-size:cover; background-position:center; color:#FFF; text-align:center;}
#section0{ background-image:url(images/1.jpg)}
#section1{ background-image:url(images/2.jpg)}
#section2{ background-image:url(images/3.jpg)}
#section3{ background-image:url(images/4.jpg)}

<div id="container">
? <div class="sections">
??? <div class="section" id="section0"><h3>this is pagefull</h3></div>
??? <div class="section" id="section1"><h3>this is pagefull</h3></div>
??? <div class="section" id="section2"><h3>this is pagefull</h3></div>
??? <div class="section" id="section3"><h3>this is pagefull</h3></div>
? </div>
</div>