diff --git a/public/index.html b/public/index.html
index ff0fa3e..e3aa9e9 100644
--- a/public/index.html
+++ b/public/index.html
@@ -10,7 +10,6 @@
       --columns: 1;
       --font-size: 12px;
       --terminal-height: 400px;
-      --wrap-mode: pre-wrap;
     }
 
     * {
@@ -243,12 +242,28 @@
       font-family: "SF Mono", Monaco, "Cascadia Code", "Courier New", monospace;
       font-size: var(--font-size);
       line-height: 1.3;
-      white-space: var(--wrap-mode);
-      word-wrap: normal;
-      overflow-wrap: normal;
       color: #e0e0e0;
     }
 
+    /* Default: wrap mode - text wraps to fit container */
+    .terminal.wrap-mode {
+      white-space: break-spaces;
+      word-break: break-word;
+      overflow-wrap: anywhere;
+    }
+
+    /* Scroll mode - horizontal scroll, no wrapping */
+    .terminal.scroll-mode {
+      white-space: pre;
+      overflow-x: auto;
+    }
+
+    /* Box-drawing lines (detected via JS) should never wrap */
+    .terminal .rule-line {
+      white-space: pre;
+      display: block;
+    }
+
     .prompt {
       background: #2a2a2a;
       border: 2px solid #ff9800;
@@ -1020,7 +1035,7 @@
         columns: 1,           // 1, 2, 3, or 'fit'
         fontSize: 12,         // px value
         terminalHeight: 400,  // px value
-        wrapText: false,      // true = pre-wrap, false = pre (horizontal scroll)
+        wrapText: true,       // true = wrap (mobile-friendly), false = scroll
       },
     };
 
@@ -1458,15 +1473,50 @@
                     title="Scroll to bottom">
               ↓
             </button>
-            <div class="terminal" id="output-${s.id}">${s.output}</div>
+            <div class="terminal ${state.settings.wrapText ? 'wrap-mode' : 'scroll-mode'}" id="output-${s.id}">${s.output}</div>
           </div>
         </div>
       `).join('');
 
-      // Initialize scroll handlers and button visibility
+      // Initialize scroll handlers, button visibility, and mark rule lines
       sessionsToRender.forEach(s => {
         initSessionOutputUI(s.id);
         updateScrollButton(s.id);
+        // Mark box-drawing lines on initial render
+        if (s.expanded) {
+          const $output = document.getElementById(`output-${s.id}`);
+          if ($output) markRuleLines($output);
+        }
+      });
+    }
+
+    // Box-drawing character range: U+2500 to U+257F
+    const BOX_DRAWING_REGEX = /[\u2500-\u257F]/g;
+
+    /**
+     * Check if a line is primarily box-drawing characters (>= 60%)
+     * Used to prevent wrapping on separator/border lines
+     */
+    function isRuleLine(text) {
+      if (!text || text.length < 3) return false;
+      const visibleChars = text.replace(/\s/g, '');
+      if (visibleChars.length < 3) return false;
+      const boxChars = (visibleChars.match(BOX_DRAWING_REGEX) || []).length;
+      return boxChars / visibleChars.length >= 0.6;
+    }
+
+    /**
+     * Process terminal output to mark box-drawing lines as rule-lines
+     * This prevents wrapping on separator/border lines
+     */
+    function markRuleLines($terminal) {
+      // xterm serializeAsHTML outputs content in divs (one per row)
+      // Each div may contain spans for styling
+      const rows = $terminal.querySelectorAll(':scope > div');
+      rows.forEach(row => {
+        if (isRuleLine(row.textContent)) {
+          row.classList.add('rule-line');
+        }
       });
     }
 
@@ -1483,6 +1533,8 @@
         // Only mutate DOM when expanded to reduce work
         if (session.expanded) {
           $output.innerHTML = session.output;
+          // Mark box-drawing lines to prevent wrapping
+          markRuleLines($output);
         }
         session.outputRenderedLength = session.output.length;
 
@@ -1979,8 +2031,16 @@
       // Apply terminal height
       root.style.setProperty('--terminal-height', `${state.settings.terminalHeight}px`);
 
-      // Apply wrap mode
-      root.style.setProperty('--wrap-mode', state.settings.wrapText ? 'pre-wrap' : 'pre');
+      // Apply wrap mode to all terminal elements
+      document.querySelectorAll('.terminal').forEach(el => {
+        if (state.settings.wrapText) {
+          el.classList.add('wrap-mode');
+          el.classList.remove('scroll-mode');
+        } else {
+          el.classList.add('scroll-mode');
+          el.classList.remove('wrap-mode');
+        }
+      });
     }
 
     function updateSettingsUI() {
diff --git a/src/server.ts b/src/server.ts
index 6f6b495..71f7485 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -458,8 +458,9 @@ const server = Bun.serve<SessionData>({
           // Initialize in-memory session state
           sessionStates.set(session.id, createDefaultSessionState());
 
-          // Create terminal emulator with default size (will be resized later)
-          const termSession = createTerminal(80, 24);
+          // Create terminal emulator wide enough to avoid premature wrapping
+          // Browser CSS handles responsive display; we just need ANSI processing
+          const termSession = createTerminal(300, 50);
           sessionTerminals.set(session.id, termSession);
 
           console.debug(