Update brand subtitle and tab labels

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: kathoc

index.html

@@ -586,16 +586,16 @@
           <span class="brand-badge"><svg viewBox="0 0 64 64" fill="none" xmlns="http://www.w3.org/2000/svg" width="22" height="22"><rect width="64" height="64" rx="10" fill="#fff" fill-opacity=".3"/><rect x="8" y="8" width="48" height="48" rx="6" fill="#fff" fill-opacity=".5"/><rect x="16" y="16" width="32" height="32" rx="4" fill="#fff"/><circle cx="64" cy="32" r="18" fill="#fff" fill-opacity=".5"/><circle cx="64" cy="32" r="9" fill="#fff"/></svg></span>
           <span class="brand-text">
             <span class="brand-name">Dropcode</span>
-            <span class="brand-sub">QRコードを送る、受け取る</span>
+            <span class="brand-sub">QRコードで送る、受け取る</span>
           </span>
         </div>
         <div class="mini-note">Static only</div>
       </div>
     </header>
 
     <nav class="tabs" aria-label="Dropcode tabs">
-      <button class="tab-button" id="tabSend" type="button" aria-selected="true" aria-controls="panelSend">作成する</button>
-      <button class="tab-button" id="tabScan" type="button" aria-selected="false" aria-controls="panelScan">読み取る</button>
+      <button class="tab-button" id="tabSend" type="button" aria-selected="true" aria-controls="panelSend">送る</button>
+      <button class="tab-button" id="tabScan" type="button" aria-selected="false" aria-controls="panelScan">受け取る</button>
     </nav>
 
     <section class="panel send-layout active" id="panelSend" aria-labelledby="tabSend">