added only

Author: khan4019

css.html

@@ -253,18 +253,16 @@ <h2>10. download resources</h2>
   </code></pre>
   <p><strong>Answer:</strong> No.</p>  
   <p><strong>reason:</strong> .</p>
-  <p>ref: <a href="http://stackoverflow.com/questions/183532/what-is-the-difference-between-html-tags-div-and-span">Stackoverflow: div vs span</a> </p>
+  <p>ref: <a href="">might add css question 18 in david shariff</a> </p>
+</div>
+<div id="div_section_article">
+  <h2>11. only</h2>
+  <p><strong>Question:</strong> What is the use of only?</p>
+  <pre><code>
+&lt;style&gt;<br/>  @media only screen and (max-width: 1024px) {<br/>    margin: 0;<br/>  }<br/>&lt;/style&gt;<br/>
+  </code></pre>
+  <p><strong>Answer:</strong> Stops older browsers from parsing the remainder of the selector</p>
 </div>
-<!-- <div id="div_section_article">
-  <h2>11. div, section & article</h2>
-  <p><strong>Question:</strong> When should i prefer div over section and vice versa?</p>
-  <p><strong>Answer:</strong> <br>&lt;section&gt; means that the content inside is grouped (i.e. relates to a single theme), and should appear as an entry in an outline of the page.  A section normally has a heading (title) and maybe a footer too. It’s a chunk of related content, like a subsection of a long article, a major part of the page (eg the news section on the homepage), or a page in a webapp’s tabbed interface.</p>
-  <p>&lt;div&gt;, on the other hand, does not convey any meaning, aside from any found in its class, lang and title attributes.</p>
-  <p>&lt;article&gt;, represents a complete, or self-contained, composition in a document, page, application, or site and that is, in principle, independently distributable or reusable, e.g. in syndication. This could be a forum post, a magazine or newspaper article, a blog entry, a user-submitted comment, an interactive widget or gadget, or any other independent item of content.</p>
-  <p><strong>Good Summary:</strong><a href="http://oli.jp/2009/html5-structure1/">div, section & article</a></p>
-  <p><strong>Extra:</strong> Authors are strongly encouraged to view the div element as an element of last resort, for when no other element is suitable. Use of more appropriate elements instead of the div element leads to better accessibility for readers and easier maintainability for authors.</p>
-  <p>ref: (copied from) <a href="http://dev.w3.org/html5/spec-author-view/the-section-element.html#the-section-element">W3C: section</a>, <a href="http://dev.w3.org/html5/spec-author-view/the-div-element.html#the-div-element">W3C: div</a>, <a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-article-element">W3c: article</a> </p>
-</div> -->
 <!-- <div id="svg_canvas">
   <h2>12. svg vs canvas</h2>
   <p><strong>Question:</strong> What are the difference between svg and canvas?</p>