diff --git a/components/ChatInputBox/ChatInputBox.tsx b/components/ChatInputBox/ChatInputBox.tsx
index 598fbe7..4d16c53 100644
--- a/components/ChatInputBox/ChatInputBox.tsx
+++ b/components/ChatInputBox/ChatInputBox.tsx
@@ -244,6 +244,11 @@ export function ChatInputBox({ noData }: { noData: boolean }) {
     }
   }, []);
 
+  // H5 文本输入框聚焦动画控制
+  const textareaRef = useRef<HTMLTextAreaElement>(null);
+  const [isInputFocused, setIsInputFocused] = useState(false);
+  const [persistedMobileMaxHeight, setPersistedMobileMaxHeight] = useState<number | null>(null);
+
   const handleCreateVideo = async () => {
     if (isCreating) return; // 如果正在创建中，直接返回
     
@@ -342,23 +347,77 @@ export function ChatInputBox({ noData }: { noData: boolean }) {
             <div data-alt="chat-input-box" className="flex flex-col w-full">
               {/* 第一行：输入框 */}
               <div className="video-prompt-editor mb-3 relative flex flex-col gap-3 flex-1 pr-10">
-                {/* 文本输入框 - 改为textarea */}
-                <textarea
-                  value={script}
-                  onChange={(e) => setScript(e.target.value)}
-                  placeholder="Describe the story you want to make..."
-                  className="w-full pl-[10px] pr-[10px] py-[14px] rounded-[10px] leading-[20px] text-sm border-none bg-transparent text-white placeholder:text-white/[0.40] focus:outline-none resize-none min-h-[48px] max-h-[120px] overflow-y-auto"
-                  style={{
-                    minHeight: noData ? "128px": "unset"
-                  }}
-                  rows={1}
-                  onInput={(e) => {
-                    const target = e.target as HTMLTextAreaElement;
-                    target.style.height = "auto";
-                    target.style.height =
-                      Math.min(target.scrollHeight, 120) + "px";
-                  }}
-                />
+              {/* 文本输入框 - 改为textarea */}
+              <textarea
+                data-alt="story-input"
+                ref={textareaRef}
+                value={script}
+                onChange={(e) => setScript(e.target.value)}
+                placeholder="Describe the story you want to make..."
+                className={`w-full pl-[10px] pr-[10px] py-[14px] rounded-[10px] leading-[20px] text-sm border-none bg-transparent text-white placeholder:text-white/[0.40] focus:outline-none resize-none overflow-y-auto transition-all duration-300 ease-in-out ${isMobile ? '' : 'max-h-[120px]'}`}
+                style={{
+                  minHeight: noData ? "128px" : (isMobile ? (isInputFocused ? "96px" : "48px") : "unset"),
+                  maxHeight: isMobile ? (isInputFocused ? "200px" : (persistedMobileMaxHeight ? `${persistedMobileMaxHeight}px` : "120px")) : undefined,
+                }}
+                rows={1}
+                onFocus={() => {
+                  if (!isMobile) return;
+                  setIsInputFocused(true);
+                  const el = textareaRef.current;
+                  if (el) {
+                    const limit = 200;
+                    // 以当前高度为起点，过渡到目标高度
+                    const start = `${el.getBoundingClientRect().height}px`;
+                    const end = `${Math.min(Math.max(el.scrollHeight, 96), limit)}px`;
+                    el.style.height = start;
+                    void el.offsetHeight;
+                    el.style.height = end;
+                  }
+                }}
+                onBlur={() => {
+                  if (!isMobile) return;
+                  setIsInputFocused(false);
+                  const el = textareaRef.current;
+                  if (el) {
+                    const baseLimit = 120;
+                    const contentHeight = el.scrollHeight;
+                    const currentHeight = el.getBoundingClientRect().height;
+                    // 若内容高度已超过基础高度，则保持较大高度，不回落
+                    if (contentHeight > baseLimit || currentHeight > baseLimit) {
+                      setPersistedMobileMaxHeight(Math.min(contentHeight, 200));
+                      el.style.height = `${Math.min(contentHeight, 200)}px`;
+                    } else {
+                      const start = `${currentHeight}px`;
+                      const end = `${Math.min(contentHeight, baseLimit)}px`;
+                      el.style.height = start;
+                      void el.offsetHeight;
+                      el.style.height = end;
+                      setPersistedMobileMaxHeight(null);
+                    }
+                  }
+                }}
+                onInput={(e) => {
+                  const target = e.target as HTMLTextAreaElement;
+                  const limit = isMobile && isInputFocused ? 200 : (persistedMobileMaxHeight ?? 120);
+                  target.style.height = "auto";
+                  target.style.height = Math.min(target.scrollHeight, limit) + "px";
+                }}
+                onTransitionEnd={() => {
+                  // 过渡结束后清理高度，避免下次动画受限
+                  if (!isMobile) return;
+                  if (!isInputFocused) {
+                    const el = textareaRef.current;
+                    if (el) {
+                      // 若已记录持久高度则保持，不清理；否则清理
+                      if (persistedMobileMaxHeight) {
+                        el.style.height = `${persistedMobileMaxHeight}px`;
+                      } else {
+                        el.style.height = "";
+                      }
+                    }
+                  }
+                }}
+              />
               </div>
 
               {/* 第二行：功能按钮和Action按钮 - 同一行 */}