diff --git a/apps/client/src/scenes/lobby/LobbyScene.tsx b/apps/client/src/scenes/lobby/LobbyScene.tsx
index dc3338f..68fa563 100644
--- a/apps/client/src/scenes/lobby/LobbyScene.tsx
+++ b/apps/client/src/scenes/lobby/LobbyScene.tsx
@@ -16,112 +16,146 @@
 
   // ロビー画面本体
   return (
-    <div
-      style={{
-        padding: 40,
-        color: "white",
-        background: "#222",
-        height: "100vh",
-        display: "flex",
-        flexDirection: "column",
-        alignItems: "center",
-      }}
-    >
-      <h2 style={{ fontSize: "2rem", marginBottom: "20px" }}>
-        ルーム: {room.roomId} (待機中)
-      </h2>
+    <>
+      {/* 🌟 追加: 縦画面のときに警告を出すCSS */}
+      <style>{`
+        .portrait-blocker {
+          display: none;
+          position: fixed;
+          top: 0; left: 0; width: 100vw; height: 100vh;
+          background: #111;
+          color: white;
+          z-index: 9999;
+          justify-content: center;
+          align-items: center;
+          flex-direction: column;
+          font-size: 1.5rem;
+          text-align: center;
+        }
+        /* 画面が縦長(portrait)の時だけ、ブロッカーを表示してロビーを隠す */
+        @media screen and (orientation: portrait) {
+          .portrait-blocker {
+            display: flex;
+          }
+          .lobby-container {
+            display: none !important;
+          }
+        }
+      `}</style>
 
+      {/* 🌟 追加: 縦画面のときに表示される警告画面 */}
+      <div className="portrait-blocker">
+        <div style={{ fontSize: "4rem", marginBottom: "20px" }}>🔄</div>
+        <p>
+          このゲームは横画面専用です。
+          <br />
+          スマホを横向きにしてください。
+        </p>
+      </div>
+
+      {/* 🌟 変更: className="lobby-container" を追加 */}
       <div
+        className="lobby-container"
         style={{
-          margin: "20px 0",
-          background: "#333",
-          padding: "20px",
-          borderRadius: "8px",
-          width: "400px",
+          padding: 40,
+          color: "white",
+          background: "#222",
+          height: "100vh",
+          display: "flex",
+          flexDirection: "column",
+          alignItems: "center",
         }}
       >
-        <h3
-          style={{
-            borderBottom: "1px solid #555",
-            paddingBottom: "10px",
-            margin: "0 0 10px 0",
-          }}
-        >
-          参加プレイヤー ({room.players.length}/{room.maxPlayers})
-        </h3>
+        <h2 style={{ fontSize: "2rem", marginBottom: "20px" }}>
+          ルーム: {room.roomId} (待機中)
+        </h2>
 
-        {/* 🌟 変更部分: ulタグにスクロール設定を追加 */}
-        <ul
+        <div
           style={{
-            listStyle: "none",
-            padding: 0,
-            margin: 0,
-            fontSize: "1.2rem",
-            maxHeight:
-              "300px" /* 🌟 リストの最大の高さを指定（これを超えるとスクロールになる） */,
-            overflowY: "auto" /* 🌟 縦方向のスクロールを有効化 */,
-            paddingRight:
-              "10px" /* 🌟 スクロールバーと文字が被らないように右側に少し余白を確保 */,
+            margin: "20px 0",
+            background: "#333",
+            padding: "20px",
+            borderRadius: "8px",
+            width: "400px",
           }}
         >
-          {/* 参加プレイヤー一覧描画 */}
-          {room.players.map((p: roomTypes.RoomMember) => (
-            <li
-              key={p.id}
+          <h3
+            style={{
+              borderBottom: "1px solid #555",
+              paddingBottom: "10px",
+              margin: "0 0 10px 0",
+            }}
+          >
+            参加プレイヤー ({room.players.length}/{room.maxPlayers})
+          </h3>
+          <ul
+            style={{
+              listStyle: "none",
+              padding: 0,
+              margin: 0,
+              fontSize: "1.2rem",
+              maxHeight: "300px",
+              overflowY: "auto",
+              paddingRight: "10px",
+            }}
+          >
+            {room.players.map((p: roomTypes.RoomMember) => (
+              <li
+                key={p.id}
+                style={{
+                  margin: "15px 0",
+                  display: "flex",
+                  alignItems: "center",
+                  gap: "10px",
+                }}
+              >
+                <span>{p.id === myId ? "🟢" : "⚪"}</span>
+                <span style={{ fontWeight: p.id === myId ? "bold" : "normal" }}>
+                  {p.name}
+                </span>
+                {p.isOwner && <span style={{ fontSize: "0.9em" }}>👑</span>}
+                {p.isReady && (
+                  <span style={{ marginLeft: "auto", fontSize: "0.9em" }}>
+                    ✅
+                  </span>
+                )}
+              </li>
+            ))}
+          </ul>
+        </div>
+
+        <div style={{ marginTop: "20px" }}>
+          {isMeOwner ? (
+            <button
+              onClick={onStart}
               style={{
-                margin: "15px 0",
-                display: "flex",
-                alignItems: "center",
-                gap: "10px",
+                padding: "15px 40px",
+                fontSize: "1.5rem",
+                cursor: "pointer",
+                backgroundColor: "#4ade80",
+                color: "#111",
+                border: "none",
+                borderRadius: "8px",
+                fontWeight: "bold",
               }}
             >
-              <span>{p.id === myId ? "🟢" : "⚪"}</span>
-              <span style={{ fontWeight: p.id === myId ? "bold" : "normal" }}>
-                {p.name}
-              </span>
-              {p.isOwner && <span style={{ fontSize: "0.9em" }}>👑</span>}
-              {p.isReady && (
-                <span style={{ marginLeft: "auto", fontSize: "0.9em" }}>
-                  ✅
-                </span>
-              )}
-            </li>
-          ))}
-        </ul>
+              ゲームスタート
+            </button>
+          ) : (
+            <div
+              style={{
+                padding: "15px 40px",
+                fontSize: "1.5rem",
+                backgroundColor: "#555",
+                color: "#ccc",
+                borderRadius: "8px",
+              }}
+            >
+              ホストの開始を待っています...
+            </div>
+          )}
+        </div>
       </div>
-
-      <div style={{ marginTop: "20px" }}>
-        {/* オーナー開始操作と待機表示の分岐 */}
-        {isMeOwner ? (
-          <button
-            onClick={onStart}
-            style={{
-              padding: "15px 40px",
-              fontSize: "1.5rem",
-              cursor: "pointer",
-              backgroundColor: "#4ade80",
-              color: "#111",
-              border: "none",
-              borderRadius: "8px",
-              fontWeight: "bold",
-            }}
-          >
-            ゲームスタート
-          </button>
-        ) : (
-          <div
-            style={{
-              padding: "15px 40px",
-              fontSize: "1.5rem",
-              backgroundColor: "#555",
-              color: "#ccc",
-              borderRadius: "8px",
-            }}
-          >
-            ホストの開始を待っています...
-          </div>
-        )}
-      </div>
-    </div>
+    </>
   );
 };
diff --git a/test/load-bot.constants.ts b/test/load-bot.constants.ts
index 3f08f20..95eb9a4 100644
--- a/test/load-bot.constants.ts
+++ b/test/load-bot.constants.ts
@@ -13,7 +13,7 @@
 export const START_DELAY_MS = 800;
 export const MAX_X = GAME_CONFIG.GRID_COLS;
 export const MAX_Y = GAME_CONFIG.GRID_ROWS;
-export const ROOM_ID = "02";
+export const ROOM_ID = "03";
 export const START_GAME = true;
 export const SOCKET_PATH = NETWORK_CONFIG.SOCKET_IO_PATH;
 export const SOCKET_TRANSPORTS = [...NETWORK_CONFIG.SOCKET_TRANSPORTS];