Move two references to informative (#194)

index.html

@@ -105,7 +105,7 @@ <h3>At-risk features</h3>
       </section>
       <section>
         <h3>Client code updates</h3>
-        <p>The W3C Technical Architecture Group released a finding called <i>The evergreen Web</i> which strongly recommends that "Browsers must be regularly updated, especially to fix security and interoperability bugs — ideally with an automatic, secure update mechanism." [[EVERGREEN-WEB]]</p>
+        <p>The W3C Technical Architecture Group released a finding called <i>The evergreen Web</i> which strongly recommends that "Browsers must be regularly updated, especially to fix security and interoperability bugs — ideally with an automatic, secure update mechanism." [[?EVERGREEN-WEB]]</p>
         <p>Devices SHOULD regularly update their browsers, preferably automatically.</p>
       </section>
       <section>
@@ -127,7 +127,7 @@ <h3>Core web specifications</h3>
       </section>
       <section>
         <h3>CSS specifications</h3>
-        <p>Devices MUST be conforming implementations of the following specifications (CSS Snapshot 2017 [[CSS-2017]]):</p>
+        <p>Devices MUST be conforming implementations of the following specifications (CSS Snapshot 2017 [[?CSS-2017]]):</p>
         <ul>
           <li>Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification [[!CSS2]]</li>
           <li>Compositing and Blending Level 1 [[!COMPOSITING]]</li>