Social banner: also hide caret on the 4 thumb tiles + 393,216 bp on model cards

- Hide .banner-cursor inside .sb-logo-stage--og so the share thumbnail
and the three model card covers export cleanly. data-static freezes
the helix; the caret is animated in CSS so it would freeze mid-blink
half the time in screenshots, leaving a random gap after the
wordmark. Live demo header keeps its cursor (editorial flourish, not
screenshotted).
- Set the three Carbon model card covers (500M / 3B / 8B) to the
actual 393,216 bp context window the checkpoints ship with, matching
the value in demo.html and llms.txt. Share thumb and main stage on
this page still read 49,152 (independent decision — flagged for
discussion).

Co-authored-by: Cursor <cursoragent@cursor.com>

social-banner.html

@@ -154,6 +154,16 @@
   .social-banner-stage .banner-path,
   .sb-logo-stage--og .banner-path  { font-size: clamp(10px, 2.2cqh, 13px); }
 
+  /* Hide the blinking caret on the 4 thumbnail tiles (share thumb +
+     three model-card covers). The caret animates in CSS, so even with
+     data-static freezing the helix, the cursor would still blink on a
+     "static" composition — which is fine on the live demo header where
+     it reads as an editorial flourish, but distracting on a still
+     export where it freezes mid-blink half the time. Main stage at the
+     top of the page keeps it (since users won't be screenshotting that
+     one, it's the live preview reference). */
+  .sb-logo-stage--og .banner-cursor { display: none; }
+
   /* Slightly stronger inset hairline replaces the bottom one we lose
      with the tabs gone — keeps the banner from looking unfinished.
      Only on the main stage: the OG tile already has a hairline coming
@@ -613,7 +623,7 @@
               <h1 class="banner-wordmark"><span>CARBON</span><span class="banner-cursor" aria-hidden="true"></span></h1>
               <p class="banner-subtitle">Autoregressive Genomic Foundation Model</p>
               <ul class="banner-specs" aria-label="Model specs">
-                <li class="banner-spec"><strong>49,152</strong> bp context</li>
+                <li class="banner-spec"><strong>393,216</strong> bp context</li>
                 <li class="banner-spec"><strong>6-mer</strong> tokenizer</li>
                 <li class="banner-spec"><strong>1T</strong> train tokens</li>
               </ul>
@@ -649,7 +659,7 @@
               <h1 class="banner-wordmark"><span>CARBON</span><span class="banner-cursor" aria-hidden="true"></span></h1>
               <p class="banner-subtitle">Autoregressive Genomic Foundation Model</p>
               <ul class="banner-specs" aria-label="Model specs">
-                <li class="banner-spec"><strong>49,152</strong> bp context</li>
+                <li class="banner-spec"><strong>393,216</strong> bp context</li>
                 <li class="banner-spec"><strong>6-mer</strong> tokenizer</li>
                 <li class="banner-spec"><strong>1T</strong> train tokens</li>
               </ul>
@@ -685,7 +695,7 @@
               <h1 class="banner-wordmark"><span>CARBON</span><span class="banner-cursor" aria-hidden="true"></span></h1>
               <p class="banner-subtitle">Autoregressive Genomic Foundation Model</p>
               <ul class="banner-specs" aria-label="Model specs">
-                <li class="banner-spec"><strong>49,152</strong> bp context</li>
+                <li class="banner-spec"><strong>393,216</strong> bp context</li>
                 <li class="banner-spec"><strong>6-mer</strong> tokenizer</li>
                 <li class="banner-spec"><strong>1T</strong> train tokens</li>
               </ul>