xdocs/dom/xml/style/definitions/CSSRuleList.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- CSSRuleList interface -->

  <interface name="CSSRuleList" id="CSS-CSSRuleList"
  since="DOM Level 2">
    <descr>
    <p>
      The <code>CSSRuleList</code> interface provides the 
      abstraction of an ordered collection of CSS rules.
    </p>
    <p>
      The items in the <code>CSSRuleList</code> are accessible via an integral
      index, starting from 0.
    </p>
    </descr>

    <attribute type="unsigned long" readonly="yes" name="length" id="CSS-CSSRuleList-length">
     <descr>
     <p>
       The number of <code>CSSRules</code> in the list. The range of valid
       child rule indices is <code>0</code> to <code>length-1</code> inclusive.
     </p>
     </descr>
    </attribute>

    <method name="item" id="CSS-CSSRuleList-item">
     <descr>
     <p>
       Used to retrieve a CSS rule by ordinal index. The order in this
       collection represents the order of the rules in the CSS style sheet. If
       index is greater than or equal to the number of rules in the list, this
       returns <code>null</code>.
     </p>
     </descr>
     <parameters>
      <param name="index" type="unsigned long" attr="in">
	<descr><p>Index into the collection</p></descr>
      </param>
     </parameters>
     <returns type="CSSRule">
      <descr><p>The style rule at the <code>index</code> position in the
         <code>CSSRuleList</code>, or <code>null</code> if 
          that is not a valid index.
      </p></descr>
     </returns>
     <raises>
      <!-- No exceptions -->
     </raises>
    </method>
  </interface>