clear - CSS: Cascading Style Sheets 编辑

The clear CSS property sets whether an element must be moved below (cleared) floating elements that precede it. The clear property applies to floating and non-floating elements.

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When applied to non-floating blocks, it moves the border edge of the element down until it is below the margin edge of all relevant floats. The non-floated block's top margin collapses.

Vertical margins between two floated elements on the other hand will not collapse. When applied to floating elements, the margin edge of the bottom element is moved below the margin edge of all relevant floats. This affects the position of later floats, since later floats cannot be positioned higher than earlier ones.

The floats that are relevant to be cleared are the earlier floats within the same block formatting context.

If an element contains only floated elements, its height collapses to nothing. If you want it to always be able to resize, so that it contains floating elements inside it, you need to self-clear its children. This is called clearfix, and one way to do it is to add clear to a replaced ::after pseudo-element on it.

#container::after {
  content: "";
  display: block;
  clear: both;
}

Syntax

/* Keyword values */
clear: none;
clear: left;
clear: right;
clear: both;
clear: inline-start;
clear: inline-end;

/* Global values */
clear: inherit;
clear: initial;
clear: unset;

Values

none

Is a keyword indicating that the element is not moved down to clear past floating elements.

left

Is a keyword indicating that the element is moved down to clear past left floats.

right

Is a keyword indicating that the element is moved down to clear past right floats.

both

Is a keyword indicating that the element is moved down to clear past both left and right floats.

inline-start

Is a keyword indicating that the element is moved down to clear floats on start side of its containing block, that is the left floats on ltr scripts and the right floats on rtl scripts.

inline-end

Is a keyword indicating that the element is moved down to clear floats on end side of its containing block, that is the right floats on ltr scripts and the left floats on rtl scripts.

Formal definition

Formal syntax

none | left | right | both | inline-start | inline-end

Examples

clear: left

HTML

<div class="wrapper">
  <p class="black">Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Phasellus sit amet diam. Duis mattis varius dui. Suspendisse eget dolor.</p>
  <p class="red">Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</p>
  <p class="left">This paragraph clears left.</p>
</div>

CSS

.wrapper{
  border:1px solid black;
  padding:10px;
}
.left {
  border: 1px solid black;
  clear: left;
}
.black {
  float: left;
  margin: 0;
  background-color: black;
  color: #fff;
  width: 20%;
}
.red {
  float: left;
  margin: 0;
  background-color: pink;
  width:20%;
}
p {
  width: 50%;
}

clear: right

HTML

<div class="wrapper">
  <p class="black">Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Phasellus sit amet diam. Duis mattis varius dui. Suspendisse eget dolor.</p>
  <p class="red">Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</p>
  <p class="right">This paragraph clears right.</p>
</div>

CSS

.wrapper{
  border:1px solid black;
  padding:10px;
}
.right {
  border: 1px solid black;
  clear: right;
}
.black {
  float: right;
  margin: 0;
  background-color: black;
  color: #fff;
  width:20%;
}
.red {
  float: right;
  margin: 0;
  background-color: pink;
  width:20%;
}
p {
  width: 50%;
}

clear: both

HTML

<div class="wrapper">
  <p class="black">Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Phasellus sit amet diam. Duis mattis varius dui. Suspendisse eget dolor. Fusce pulvinar lacus ac dui.</p>
  <p class="red">Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Phasellus sit amet diam. Duis mattis varius dui. Suspendisse eget dolor.</p>
  <p class="both">This paragraph clears both.</p>
</div>

CSS

.wrapper{
  border:1px solid black;
  padding:10px;
}
.both {
  border: 1px solid black;
  clear: both;
}
.black {
  float: left;
  margin: 0;
  background-color: black;
  color: #fff;
  width:20%;
}
.red {
  float: right;
  margin: 0;
  background-color: pink;
  width:20%;
}
p {
  width: 45%;
}

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• CSS basic box model