如何让我的页脚从顶部覆盖 100% 的页面高度和宽度？

Question

我有一个带有 header、页脚和内容的 html 页面。 当用户点击我的页脚时，我希望页脚从顶部开始覆盖整个页面。 当我将页脚的高度和宽度设置为 100vh 和 100vw 时。 它是从底部开始的。 我如何使它从顶部覆盖？

Answer 1

您需要使用percentage %而不是vh/vw/px 。 您需要设置top:0; 和height: 100% （设备屏幕的全高）。

 function toggle() { var className = document.getElementById('footer').className; if (className == 'footer') { document.getElementById('footer').innerText = 'Click to minimize'; document.getElementById('footer').className = 'footer full'; } else { document.getElementById('footer').innerText = 'Click to miximize'; document.getElementById('footer').className = 'footer'; } }

 .footer { background-color: #000; color: #FFF; width: 100%; padding: 20px 0; }.full { height: 100%; width: 100%; position: fixed; top: 0px; left: 0px; }

 <h1>My heading</h1> <p> Hello, this click on the footer to expand it. </p> <br> <p> Hello, this click on the footer to expand it. </p> <br> <p> Hello, this click on the footer to expand it. </p> <br> <p> Hello, this click on the footer to expand it. </p> <br> <p> Hello, this click on the footer to expand it. </p> <br> <p> Hello, this click on the footer to expand it. </p> <br> <p> Hello, this click on the footer to expand it. </p> <br> <p> Hello, this click on the footer to expand it. </p> <br> <p> Hello, this click on the footer to expand it. </p> <br> <p> Hello, this click on the footer to expand it. </p> <br> <div id='footer' class='footer' onClick='toggle()'> Click to maximise </div>

Answer 2

尝试这个：

$('.footer').click(function(){
        $(this).toggleClass('new_footer');
    });



.new_footer{
    background-color: #000;
    position: fixed;
    top: 0;'
    left: 0;
    right: 0;
    bottom: 0;
    height: 100vh;
    width: 100%;
    color: #fff;
}

<header>
  My heaader
</header>

<div>content</div>

<div class="footer">
 My footer
</div>