Update index.html

Author: lhmd

index.html

@@ -39,7 +39,7 @@
       <h1 class="hero-project">World-R1</h1>
       <p class="hero-title">Reinforcing 3D Constraints for Text-to-Video Generation</p>
       <div class="hero-actions">
-        <a class="action primary placeholder-action" href="#" aria-disabled="true">PDF</a>
+        <a class="action primary placeholder-action" href="#" aria-disabled="true">Tech Report</a>
         <a class="action ghost" href="tech.html">Technical Details</a>
         <a class="action ghost" href="https://github.com/microsoft/World-R1" target="_blank" rel="noopener noreferrer">GitHub</a>
       </div>