[css-link-params] Specify that & is used between params in a URL. w3c#9051

Author: tabatkins

css-link-params-1/Overview.bs

@@ -19,6 +19,7 @@ spec:html; type:element
 	text: iframe
 	text: a
 spec:fill-stroke-3; type:property; text:fill
+spec:css-env-1; type:function; text:env()
 </pre>
 
 Introduction {#intro}
@@ -178,11 +179,14 @@ The syntax of an <dfn export local-lt="param()">SVG parameter fragment identifie
 
 Multiple [=link parameters=] can be passed to an image
 by appending multiple [=param()=] fragment identifiers to the URL.
+When combined, either with each other or with other "fragment identifiers",
+each value is separated with an <code>&</code> character,
+as in a URL's query parameters.
 
 <div class="example">
 	For example, if the image from the previous example also used ''env(--bg-color)'',
 	it could be referenced with a url like
-	“<code>http://example.com/image.svg#param(--text-color,blue)param(--bg-color,white)</code>”
+	“<code>http://example.com/image.svg#param(--text-color,blue)&param(--bg-color,white)</code>”
 	to set both ''env(--text-color)'' and ''env(--bg-color)''.
 </div>