html - 页面底部的 CSS 空白

Question

如何去掉页面底部的空格？

/* Basic Style */

html,
body {
  height: 100%;
}
body {
  background-color: #FFFFFF;
  font-family: 'Roboto', sans-serif;
  font-size: 12pt;
  font-weight: 100;
  color: #212121;
  text-decoration: none;
  line-height: 100%;
  height: 100%;
  margin: 0px 0px 0px 0px;
}
a:link {
  color: #42b4da;
  font-family: 'Roboto', sans-serif;
  text-decoration: none;
}
a:visited {
  color: #002946;
  text-decoration: none;
}
a:active,
a:hover {
  color: #670f08;
  text-decoration: underline;
}
img {
  border: 0px solid white;
  margin: 0px;
  padding: 0px;
}
.clear {
  clear: both;
}
/* Text Formatting */

h1 {
  font-size: 20pt;
  color: #212121;
  font-weight: lighter;
}
h2 {
  font-size: 20pt;
  color: #212121;
  font-weight: lighter;
}
h3 {
  font-size: 20pt;
  color: #212121;
  font-weight: lighter;
}
blockquote {
  font-size: 12pt;
  font-style: italic;
  margin: 30px 30px 30px 0;
  padding: 0 0 0 20px;
  border-left: 1px solid #ccc;
}
/* Clear */

.clearBoth {
  clear: both;
}
/* Page Wrapper*/

#pageWrapper {
  width: 100%;
  height: 100%;
}
/* Page Top */

#pageTop {
  width: 100%;
  height: 100px;
  position: fixed;
  top: 0;
  left: 0;
  z-index: 100;
  overflow: hidden;
}
#topTitle {
  background-color: #262626;
  color: #CCCCCC;
  width: 100%;
  height: 100%;
  float: left;
  margin-right: -250px;
}
#topRight {
  background-color: #262626;
  color: #CCCCCC;
  width: 250px;
  height: 100%;
  float: right;
}
/* Page Main */

#pageMain {
  background: #ffffff url(../style/images/sidebarBackground.gif) repeat-y right;
  width: 100%;
  margin-top: 100px;
  overflow: hidden;
}
/* Main Content */

#mainContent {
  width: 100%;
  height: 100%;
  float: left;
  margin-right: -250px;
}
.contentClear {
  margin-right: 250px;
}
.contentPost {
  margin: 40px;
}
.postTitle {} .postContent {} .postExtras {}
/* Main Sidebar */

#mainSidebar {
  background: #262626 url(../style/images/sidebarBackground.gif) repeat-y right;
  color: #CCCCCC;
  width: 220px;
  margin: 15px;
  height: 100%;
  float: right;
}
#mainSidebar h1 {
  color: #CCCCCC;
  font: 14pt'Roboto', sans-serif;
  text-align: center;
  margin: 2px;
  padding: 2px;
}
#mainSidebar h1:before {
  content: "‹";
  position: relative;
  left: -2px;
}
#mainSidebar h1:after {
  content: "›";
  position: relative;
  left: 2px;
}
.sidebarContent {} .sidebarNav {
  margin: 0;
  padding: 0;
  list-style: none;
}
.sidebarNav li:before {
  content: "//";
  position: relative;
  left: 2px;
}
/* Page Footer */

#pageFooter {
  width: 100%;
  height: 100px;
  overflow: hidden;
}
#footerContent {
  background-color: #262626;
  color: #CCCCCC;
  width: 100%;
  height: 100%;
  float: left;
  margin-right: -250px;
}
#footerRight {
  background-color: #262626;
  color: #CCCCCC;
  width: 250px;
  height: 100%;
  float: right;
}

<div id="pageWrapper">
  <div id="pageTop">
    <div id="topTitle">
      This is where the pages logo/title/whatever will go.
    </div>
    <div id="topRight">
      Rightside content
    </div>
  </div>
  <div class="clearBoth"></div>
  <div id="pageMain">
    <div id="mainContent">
      <div class="contentClear">
        <div class="contentPost">
          <div class="postTitle">
            <h1>HELLO WORLD!</h1>
          </div>
          <div class="postExtras">
            <p>
              APRIL 2, 2015 1 COMMENT
            </p>
          </div>
          <div class="postContent">
            <p>
              Welcome to WordPress. This is your first post. Edit or delete it, then start blogging!
            </p>
            <p>
              This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts
              content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!!
            </p>
          </div>
        </div>
      </div>
    </div>
    <div id="mainSidebar">
      <div class="sidebarContent">
        <h1>Navigation</h1>
        <ul class="sidebarNav">
          <li>
            <a href="_blank">Home</a>
          </li>
          <li>
            <a href="_blank">About</a>
          </li>
          <li>
            <a href="_blank">Contact</a>
          </li>
          <li>
            <a href="_blank">Links</a>
          </li>
        </ul>
      </div>
      <div class="sidebarContent">
        <h1>Unordered List</h1>
        <ul>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
        </ul>
      </div>
      <div class="sidebarContent">
        <h1>Something Else</h1>
        <ol>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
        </ol>
      </div>
    </div>
  </div>
  <div class="clearBoth"></div>
  <div id="pageFooter">
    <div id="footerContent">
      <h1>This is the footer, and copyright stuff.</h1>
      <ul>
        <li>
          <a href="_blank">Home</a>
        </li>
        <li>
          <a href="_blank">About</a>
        </li>
        <li>
          <a href="_blank">Contact</a>
        </li>
        <li>
          <a href="_blank">Links</a>
        </li>
      </ul>
    </div>
    <div id="footerRight">
      <p>
        SMLinks
      </p>
    </div>
  </div>
</div>

Answer 1

如果我理解正确，问题是即使没有内容填充该滚动区域，也会有一个持续的垂直滚动条。

我相信这是由 "margin collapse" 引起的.

margin 暴跌的解释

您已设置 div#pageTop至 position:fixed你已经添加了margin-top:100px至 div#pageMain将其向下推到固定标题下方。该边距随着 div#pageWrapper 崩溃最终与 <body> .

自 <body>设置为 height:100%折叠边距将其向下推 100 像素，<body>最终会因为 100px 太高而导致浏览器出现垂直滚动条。 100% + 100px 的高度将总是大于窗口的高度并且总是需要滚动条。

下图显示了 <body> 的顶部.请注意，它不会按预期从页面顶部开始。它从标题下方 100px 开始:

如何修复折叠边距

有several methods以防止边距坍塌。在这种情况下，我建议更改 margin-top:100px在 div#pageMain进入填充:

#pageMain {
  ...
  padding-top: 100px; /* padding instead of margin */
}

这会阻止边距崩溃并带来 <body>回到它所属窗口的顶部:

现在 <body> 的高度是 100% 的窗口，没有持久的滚动条。

请看下面的演示:

/* Basic Style */

html,
body {
  height: 100%;
}
body {
  background-color: #FFFFFF;
  font-family: 'Roboto', sans-serif;
  font-size: 12pt;
  font-weight: 100;
  color: #212121;
  text-decoration: none;
  line-height: 100%;
  height: 100%;
  margin: 0px 0px 0px 0px;
}
a:link {
  color: #42b4da;
  font-family: 'Roboto', sans-serif;
  text-decoration: none;
}
a:visited {
  color: #002946;
  text-decoration: none;
}
a:active,
a:hover {
  color: #670f08;
  text-decoration: underline;
}
img {
  border: 0px solid white;
  margin: 0px;
  padding: 0px;
}
.clear {
  clear: both;
}
/* Text Formatting */

h1 {
  font-size: 20pt;
  color: #212121;
  font-weight: lighter;
}
h2 {
  font-size: 20pt;
  color: #212121;
  font-weight: lighter;
}
h3 {
  font-size: 20pt;
  color: #212121;
  font-weight: lighter;
}
blockquote {
  font-size: 12pt;
  font-style: italic;
  margin: 30px 30px 30px 0;
  padding: 0 0 0 20px;
  border-left: 1px solid #ccc;
}
/* Clear */

.clearBoth {
  clear: both;
}
/* Page Wrapper*/

#pageWrapper {
  width: 100%;
  height: 100%;
}
/* Page Top */

#pageTop {
  width: 100%;
  height: 100px;
  position: fixed;
  top: 0;
  left: 0;
  z-index: 100;
  overflow: hidden;
}
#topTitle {
  background-color: #262626;
  color: #CCCCCC;
  width: 100%;
  height: 100%;
  float: left;
  margin-right: -250px;
}
#topRight {
  background-color: #262626;
  color: #CCCCCC;
  width: 250px;
  height: 100%;
  float: right;
}
/* Page Main */

#pageMain {
  background: #ffffff url(../style/images/sidebarBackground.gif) repeat-y right;
  width: 100%;
  padding-top: 100px;
  overflow: hidden;
}
/* Main Content */

#mainContent {
  width: 100%;
  height: 100%;
  float: left;
  margin-right: -250px;
}
.contentClear {
  margin-right: 250px;
}
.contentPost {
  margin: 40px;
}
.postTitle {} .postContent {} .postExtras {}
/* Main Sidebar */

#mainSidebar {
  background: #262626 url(../style/images/sidebarBackground.gif) repeat-y right;
  color: #CCCCCC;
  width: 220px;
  margin: 15px;
  height: 100%;
  float: right;
}
#mainSidebar h1 {
  color: #CCCCCC;
  font: 14pt'Roboto', sans-serif;
  text-align: center;
  margin: 2px;
  padding: 2px;
}
#mainSidebar h1:before {
  content: "‹";
  position: relative;
  left: -2px;
}
#mainSidebar h1:after {
  content: "›";
  position: relative;
  left: 2px;
}
.sidebarContent {} .sidebarNav {
  margin: 0;
  padding: 0;
  list-style: none;
}
.sidebarNav li:before {
  content: "//";
  position: relative;
  left: 2px;
}
/* Page Footer */

#pageFooter {
  width: 100%;
  height: 100px;
  overflow: hidden;
}
#footerContent {
  background-color: #262626;
  color: #CCCCCC;
  width: 100%;
  height: 100%;
  float: left;
  margin-right: -250px;
}
#footerRight {
  background-color: #262626;
  color: #CCCCCC;
  width: 250px;
  height: 100%;
  float: right;
}

<div id="pageWrapper">
  <div id="pageTop">
    <div id="topTitle">
      This is where the pages logo/title/whatever will go.
    </div>
    <div id="topRight">
      Rightside content
    </div>
  </div>
  <div class="clearBoth"></div>
  <div id="pageMain">
    <div id="mainContent">
      <div class="contentClear">
        <div class="contentPost">
          <div class="postTitle">
            <h1>HELLO WORLD!</h1>
          </div>
          <div class="postExtras">
            <p>
              APRIL 2, 2015 1 COMMENT
            </p>
          </div>
          <div class="postContent">
            <p>
              Welcome to WordPress. This is your first post. Edit or delete it, then start blogging!
            </p>
            <p>
              This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts
              content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!!
            </p>
          </div>
        </div>
      </div>
    </div>
    <div id="mainSidebar">
      <div class="sidebarContent">
        <h1>Navigation</h1>
        <ul class="sidebarNav">
          <li>
            <a href="_blank">Home</a>
          </li>
          <li>
            <a href="_blank">About</a>
          </li>
          <li>
            <a href="_blank">Contact</a>
          </li>
          <li>
            <a href="_blank">Links</a>
          </li>
        </ul>
      </div>
      <div class="sidebarContent">
        <h1>Unordered List</h1>
        <ul>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
        </ul>
      </div>
      <div class="sidebarContent">
        <h1>Something Else</h1>
        <ol>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
          <li>
            Here is an unordered list in the sidebar.
          </li>
        </ol>
      </div>
    </div>
  </div>
  <div class="clearBoth"></div>
  <div id="pageFooter">
    <div id="footerContent">
      <h1>This is the footer, and copyright stuff.</h1>
      <ul>
        <li>
          <a href="_blank">Home</a>
        </li>
        <li>
          <a href="_blank">About</a>
        </li>
        <li>
          <a href="_blank">Contact</a>
        </li>
        <li>
          <a href="_blank">Links</a>
        </li>
      </ul>
    </div>
    <div id="footerRight">
      <p>
        SMLinks
      </p>
    </div>
  </div>
</div>

jlane09 的回答也解决了这个问题。它具有有效性，因为它有效。但是，在我看来，这个答案并不能充分解释问题的原因。此外，使用 height:auto在某些情况下可能会导致更多问题(例如，对子元素使用基于百分比的高度)。

---

粘性页脚

创建“粘性”页脚是一个单独的问题。如果您希望无论窗口是否需要滚动，页脚始终贴在窗口底部，请参阅 Ryan Fait's (famous) sticky footer .它需要稍微不同的结构，但这是值得的。

我为您构建了一个基本演示，如下所示:

/* Basic Style */

html,
body {
  height: 100%;
  margin: 0;
}
/* Page Wrapper*/

#pageWrapper {
  min-height: 100%;
  height: auto !important;
  height: 100%;
  margin: 0 0 -160px;
}
/* Page Top */

#pageTop {
  width: 100%;
  height: 100px;
  position: fixed;
  top: 0;
  left: 0;
  z-index: 100;
}
#topTitle {
  background-color: #262626;
  color: #CCCCCC;
  width: 100%;
  height: 100%;
  float: left;
  margin-right: -250px;
}
#topRight {
  background-color: #262626;
  color: #CCCCCC;
  width: 250px;
  height: 100%;
  float: right;
}
/* Page Main */

#pageMain {
  background: #ffffff url(../style/images/sidebarBackground.gif) repeat-y right;
  width: 100%;
  padding-top: 100px;
}
/* Main Content */

#mainContent {
  width: 100%;
  height: 100%;
  float: left;
  margin-right: -250px;
}
.contentClear {
  margin-right: 250px;
}
.contentPost {
  margin: 40px;
}
.postTitle {} .postContent {} .postExtras {}
/* Main Sidebar */

#mainSidebar {
  background: #262626 url(../style/images/sidebarBackground.gif) repeat-y right;
  color: #CCCCCC;
  width: 220px;
  margin: 15px;
  height: 100%;
  float: right;
}
#mainSidebar h1 {
  color: #CCCCCC;
  font: 14pt'Roboto', sans-serif;
  text-align: center;
  margin: 2px;
  padding: 2px;
}
#mainSidebar h1:before {
  content: "‹";
  position: relative;
  left: -2px;
}
#mainSidebar h1:after {
  content: "›";
  position: relative;
  left: 2px;
}
.sidebarContent {} .sidebarNav {
  margin: 0;
  padding: 0;
  list-style: none;
}
.sidebarNav li:before {
  content: "//";
  position: relative;
  left: 2px;
}
/* Page Footer */

#pageFooter {
  width: 100%;
  background-color: #262626;
}
#footerContent {
  color: #CCCCCC;
  width: 100%;
  float: left;
  margin-right: -250px;
}
#footerRight {
  color: #CCCCCC;
  width: 250px;
  height: 100%;
  float: right;
}
#pageFooter,
#footer_push {
  height: 160px;
}
.clearfix:before,
.clearfix:after {
  content: "";
  display: table;
}
.clearfix:after {
  clear: both;
}
.clearfix {
  zoom: 1;
  /* ie 6/7 */
}

<div id="pageWrapper">
  <div id="pageTop">
    <div id="topTitle">This is where the pages logo/title/whatever will go.</div>
    <div id="topRight">Rightside content</div>
  </div>
  <div id="pageMain" class="clearfix">
    <div id="mainContent">
      <div class="contentClear">
        <div class="contentPost">
          <div class="postTitle">
            <h1>HELLO WORLD!</h1>

          </div>
          <div class="postExtras">
            <p>APRIL 2, 2015 1 COMMENT</p>
          </div>
          <div class="postContent">
            <p>Welcome to WordPress. This is your first post. Edit or delete it, then start blogging!</p>
            <p>This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This
              is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!! This is the posts content; yeah!!</p>
          </div>
        </div>
      </div>
    </div>
    <div id="mainSidebar">
      <div class="sidebarContent">
        <h1>Navigation</h1>

        <ul class="sidebarNav">
          <li> <a href="_blank">Home</a>

          </li>
          <li> <a href="_blank">About</a>

          </li>
          <li> <a href="_blank">Contact</a>

          </li>
          <li> <a href="_blank">Links</a>

          </li>
        </ul>
      </div>
      <div class="sidebarContent">
        <h1>Unordered List</h1>

        <ul>
          <li>Here is an unordered list in the sidebar.</li>
          <li>Here is an unordered list in the sidebar.</li>
          <li>Here is an unordered list in the sidebar.</li>
          <li>Here is an unordered list in the sidebar.</li>
        </ul>
      </div>
      <div class="sidebarContent">
        <h1>Something Else</h1>

        <ol>
          <li>Here is an unordered list in the sidebar.</li>
          <li>Here is an unordered list in the sidebar.</li>
          <li>Here is an unordered list in the sidebar.</li>
          <li>Here is an unordered list in the sidebar.</li>
        </ol>
      </div>
    </div>
  </div>
  <div id="footer_push"></div>
</div>
<div id="pageFooter">
  <div id="footerContent">
    <h1>This is the footer, and copyright stuff.</h1>

    <ul>
      <li> <a href="_blank">Home</a>

      </li>
      <li> <a href="_blank">About</a>

      </li>
      <li> <a href="_blank">Contact</a>

      </li>
      <li> <a href="_blank">Links</a>

      </li>
    </ul>
  </div>
  <div id="footerRight">
    <p>SMLinks</p>
  </div>
</div>