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Add the resolution unit, since it's used in two specs (MQ and Images)
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‎css3-values/Overview.html‎

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<h1>CSS Values and Units Module Level 3</h1>
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<h2 class="no-num no-toc" id=longstatus-date>Editor's Draft 5 January 2012</h2>
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<h2 class="no-num no-toc" id=longstatus-date>Editor's Draft 7 February
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2012</h2>
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<dl>
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<dt>This version:
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<dd><a
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href="http://www.w3.org/TR/2012/ED-css3-values-20120105/">http://www.w3.org/TR/2012/ED-css3-values-20120105/</a>
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href="http://www.w3.org/TR/2012/ED-css3-values-20120207/">http://www.w3.org/TR/2012/ED-css3-values-20120207/</a>
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<dt>Latest version:
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class=css>s</code>&rsquo;, &lsquo;<code class=css>ms</code>&rsquo;
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units</a>
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<li><a href="#frequencies-the-ltfrequencygt-type-and-h"><span
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class=secno>6.3. </span>Frequencies: the &lsquo;<code
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class=css>&lt;frequency&gt;</code>&rsquo; type and &lsquo;<code
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class=css>Hz</code>&rsquo;, &lsquo;<code class=css>kHz</code>&rsquo;
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units</a>
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<li><a href="#frequency"><span class=secno>6.3. </span> Frequencies: the
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&lsquo;<code class=css>&lt;frequency&gt;</code>&rsquo; type and
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&lsquo;<code class=css>Hz</code>&rsquo;, &lsquo;<code
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class=css>kHz</code>&rsquo; units</a>
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<li><a href="#resolution"><span class=secno>6.4. </span> Resolutions:
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the &lsquo;<code class=css>dpi</code>&rsquo;, &lsquo;<code
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class=css>dpcm</code>&rsquo;, and &lsquo;<code
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class=css>dppx</code>&rsquo; units</a>
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</ul>
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<li><a href="#defined-elsewhere"><span class=secno>7. </span> Data Types
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outside the allowed range, the declaration is invalid and must be <a
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href="http://www.w3.org/TR/CSS21/conform.html#ignore">ignored</a>.
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<h3 id=frequencies-the-ltfrequencygt-type-and-h><span class=secno>6.3.
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</span>Frequencies: the &lsquo;<a href="#frequency-value"><code
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<h3 id=frequency><span class=secno>6.3. </span> Frequencies: the &lsquo;<a
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href="#frequency-value"><code
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class=css>&lt;frequency&gt;</code></a>&rsquo; type and &lsquo;<a
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href="#hz"><code class=css>Hz</code></a>&rsquo;, &lsquo;<a
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href="#khz"><code class=css>kHz</code></a>&rsquo; units</h3>
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<p>For example, when representing sound pitches, 200Hz (or 200hz) is a bass
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sound, and 6kHz (or 6khz) is a treble sound.
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<h3 id=resolution><span class=secno>6.4. </span> Resolutions: the &lsquo;<a
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href="#dpi"><code class=css>dpi</code></a>&rsquo;, &lsquo;<a
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href="#dpcm"><code class=css>dpcm</code></a>&rsquo;, and &lsquo;<a
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href="#dppx"><code class=css>dppx</code></a>&rsquo; units</h3>
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<p>Resolution units are <i>dimensions</i> denoted by <dfn
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id=resolution-value>&lt;resolution></dfn>. The frequency unit identifiers
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are:
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<dl>
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<dt><dfn id=dpi>dpi</dfn>
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<dd>dots per inch
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<dt><dfn id=dpcm>dpcm</dfn>
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<dd>dots per centimeter
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<dt><dfn id=dppx>dppx</dfn>
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<dd>dots per &lsquo;<code class=css>px</code>&rsquo; unit
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</dl>
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<p>The &lsquo;<a href="#resolution-value"><code
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class=css>&lt;resolution></code></a>&rsquo; unit represents the size of a
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single "dot" in a graphical representation by indicating how many of these
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dots fit in a CSS &lsquo;<code class=property>in</code>&rsquo;,
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&lsquo;<code class=property>cm</code>&rsquo;, or &lsquo;<code
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class=property>px</code>&rsquo;. For uses, see e.g. the &lsquo;<code
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class=css>resolution</code>&rsquo; media query in <a href="#MEDIAQ"
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rel=biblioentry>[MEDIAQ]<!--{{MEDIAQ}}--></a> or the &lsquo;<code
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class=property>image-resolution</code>&rsquo; property defined in
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[[CSS3IMAGES]].
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<p class=note>Note that due to the 1:96 fixed ratio of CSS &lsquo;<code
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class=css>in</code>&rsquo; to CSS &lsquo;<code class=css>px</code>&rsquo;,
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&lsquo;<code class=css>1dppx</code>&rsquo; is equivalent to &lsquo;<code
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class=css>96dpi</code>&rsquo;. This corresponds to the default resolution
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of images displayed in CSS: see &lsquo;<code
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class=property>image-resolution</code>&rsquo;.
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<div class=example>
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<p>The following @media rule uses Media Queries <a href="#MEDIAQ"
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rel=biblioentry>[MEDIAQ]<!--{{MEDIAQ}}--></a> to assign some special
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style rules to devices that use two or more device pixels per CSS
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&lsquo;<code class=css>px</code>&rsquo; unit:
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<pre>@media (min-resolution: 2dppx) { ... }</pre>
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</div>
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<h2 id=defined-elsewhere><span class=secno>7. </span> Data Types Defined
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Elsewhere</h2>
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</dd>
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<!---->
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<dt id=MEDIAQ>[MEDIAQ]
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<dd>H&#229;kon Wium Lie; et al. <a
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href="http://www.w3.org/TR/2010/CR-css3-mediaqueries-20100727/"><cite>Media
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Queries.</cite></a> 27 July 2010. W3C Candidate Recommendation. (Work in
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progress.) URL: <a
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href="http://www.w3.org/TR/2010/CR-css3-mediaqueries-20100727/">http://www.w3.org/TR/2010/CR-css3-mediaqueries-20100727/</a>
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</dd>
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<!---->
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<dt id=URI>[URI]
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<dd>T. Berners-Lee; R. Fielding; L. Masinter. <a
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<li>dimension, <a href="#dimension"
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title=dimension><strong>5.</strong></a>
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<li>dpcm, <a href="#dpcm" title=dpcm><strong>6.4.</strong></a>
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<li>dpi, <a href="#dpi" title=dpi><strong>6.4.</strong></a>
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<li>dppx, <a href="#dppx" title=dppx><strong>6.4.</strong></a>
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<li>em, <a href="#em-unit" title=em><strong>5.1.1.</strong></a>
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<li>ex, <a href="#ex-unit" title=ex><strong>5.1.1.</strong></a>
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<li>rem, <a href="#rem-unit" title=rem><strong>5.1.1.</strong></a>
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<li>&lt;resolution>, <a href="#resolution-value"
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title="&lt;resolution>"><strong>6.4.</strong></a>
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<li>resolved type, <a href="#resolved-type"
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title="resolved type"><strong>8.1.</strong></a>
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‎css3-values/Overview.src.html‎

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If the value is outside the allowed range, the declaration is invalid
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and must be <a href="http://www.w3.org/TR/CSS21/conform.html#ignore">ignored</a>.
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<h3>Frequencies: the ''&lt;frequency&gt;'' type and ''Hz'', ''kHz'' units</h3>
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<h3 id="frequency">
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Frequencies: the ''&lt;frequency&gt;'' type and ''Hz'', ''kHz'' units</h3>
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<p>Frequency values are <i>dimensions</i> denoted by
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<dfn id="frequency-value">&lt;frequency&gt;</dfn>.
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<p>For example, when representing sound pitches, 200Hz (or 200hz)
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is a bass sound, and 6kHz (or 6khz) is a treble sound.</p>
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<h3 id="resolution">
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Resolutions: the ''dpi'', ''dpcm'', and ''dppx'' units</h3>
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<p>Resolution units are <i>dimensions</i> denoted by <dfn id="resolution-value">&lt;resolution></dfn>. The frequency unit identifiers are:</p>
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<dl>
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<dt><dfn>dpi</dfn></dt>
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<dd>dots per inch</dd>
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<dt><dfn>dpcm</dfn></dt>
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<dd>dots per centimeter</dd>
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<dt><dfn>dppx</dfn></dt>
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<dd>dots per ''px'' unit</dd>
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</dl>
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<p>The ''&lt;resolution>'' unit represents the size of a single "dot" in a
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graphical representation by indicating how many of these dots fit in a
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CSS 'in', 'cm', or 'px'.
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For uses, see e.g. the ''resolution'' media query in [[MEDIAQ]]
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or the 'image-resolution' property defined in [[CSS3IMAGES]].
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<p class="note">Note that due to the 1:96 fixed ratio of CSS ''in'' to
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CSS ''px'', ''1dppx'' is equivalent to ''96dpi''. This corresponds to
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the default resolution of images displayed in CSS: see 'image-resolution'.
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<div class="example">
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<p>The following @media rule uses Media Queries [[MEDIAQ]] to assign
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some special style rules to devices that use two or more device pixels
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per CSS ''px'' unit:
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<pre>@media (min-resolution: 2dppx) { ... }</pre>
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</div>
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<h2 id="defined-elsewhere">
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Data Types Defined Elsewhere</h2>
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