docs: final review fixes — deferred backlog, doc accuracy, sample-data note

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/index.html

@@ -10,7 +10,7 @@
 <body>
   <main>
     <h1>EPIC: The Musical Timeline</h1>
-    <p class="lede">Seven design directions for an interactive timeline. Pick one, or mix several.</p>
+    <p class="lede">Seven design directions for an interactive timeline. Pick one, or mix several. Sample content: placeholder lyrics and unverified details, for comparing designs only.</p>
     <ul class="cards">
       <li class="card"><a href="/mockups/01-editorial/"><span class="card__num">01</span><h2>Editorial scroll</h2><p>A clean horizontal line in a parchment-and-serif editorial style, with motifs as thin coloured threads underneath.</p><p class="card__try">Try this: Pan sideways, notice gap length tracking in-story time, and open a song.</p></a></li>
       <li class="card"><a href="/mockups/02-vertical-story/"><span class="card__num">02</span><h2>Vertical story</h2><p>The voyage scrolls downward; songs reveal one at a time beside a sticky detail panel.</p><p class="card__try">Try this: Scroll and watch the sticky detail panel update.</p></a></li>