diff --git a/components/RankingPanel.tsx b/components/RankingPanel.tsx
index 1eaa250..5f0dc39 100644
--- a/components/RankingPanel.tsx
+++ b/components/RankingPanel.tsx
@@ -27,12 +27,18 @@ export default function RankingPanel() {
     likes: []
   })
   const [loading, setLoading] = useState(true)
-  const [position, setPosition] = useState<Position>({ x: 32, y: window.innerHeight / 2 - 200 })
+  const [position, setPosition] = useState<Position>(() => ({
+    x: 32,
+    y: typeof window === 'undefined' ? 200 : window.innerHeight / 2 - 200,
+  }))
   const [isDragging, setIsDragging] = useState(false)
   const [dragOffset, setDragOffset] = useState<Position>({ x: 0, y: 0 })
   const panelRef = useRef<HTMLDivElement>(null)
   const buttonRef = useRef<HTMLButtonElement>(null)
-  const [buttonPosition, setButtonPosition] = useState<Position>({ x: 32, y: window.innerHeight / 2 - 24 })
+  const [buttonPosition, setButtonPosition] = useState<Position>(() => ({
+    x: 32,
+    y: typeof window === 'undefined' ? 200 : window.innerHeight / 2 - 24,
+  }))
   const [isButtonDragging, setIsButtonDragging] = useState(false)
   const [buttonDragOffset, setButtonDragOffset] = useState<Position>({ x: 0, y: 0 })
   const clickStartRef = useRef<{ x: number; y: number; time: number } | null>(null)