雙語對照翻譯 — 網頁與 YouTube 字幕

免費網頁雙語對照：原文一行、譯文一行。支援任何網頁（Alt+A）、X、Reddit 與 YouTube 雙語字幕。預設免費引擎、免 API 金鑰，繁簡中文皆可。

【雙語對照翻譯】把任何外文內容變成「原文一行、中文一行」的對照閱讀，幫你更快讀懂、順便學語言。完全免費、預設免 API 金鑰。 ■ 主要功能 - 任何網頁：點工具列圖示 →「翻譯這個網頁」，或按 Alt+A，一鍵整頁雙語；再操作一次即關閉。採用通用版面偵測，連 Facebook 等以 div/span 排版的現代網站也能抓到內文。 - X / Twitter、Reddit：開啟後自動雙語顯示；按 Alt+A（或按鈕）可隨時隱藏／顯示翻譯、切回原文。 - YouTube：影片字幕雙語對照，像電影字幕一樣一句一句跟著聲音，中文在上、英文在下（可調整）；按 Alt+A 可切回原本字幕。 - 雙擊單字浮窗（選用，預設關閉）：在任何網頁雙擊單字或反白詞句，就地浮出原文＋🔊 朗讀、翻譯，單字還附字典卡。此功能開啟時才會請求「在所有網站執行」權限，關閉即一併撤除。 - 繁體 / 簡體中文一鍵切換。 - 多種譯文樣式：底線、框線、醒目提示、斜體、粗體，以及「學習模式」（中文先模糊，滑過才顯示，逼自己先看原文）。 - 可自訂譯文顏色與字體大小。 ■ 翻譯品質 - 翻譯時會參考頁面標題作為背景脈絡，讓產品名、專有名詞更不容易被誤譯。 - 長段落採整段對照，跨行語意更連貫、閱讀更通順。 ■ 翻譯引擎（永遠免費） - 預設使用免費引擎，零設定、免金鑰即可使用。 - 內建兩個免費引擎：當 Google 免費端點偶爾被限流時，會自動改用 Microsoft 免費端點，讓翻譯不中斷。 - 進階（皆為選用）：可自行填入 Gemini / OpenAI 金鑰，或連接你本機的 Ollama，獲得更高品質或完全本地的翻譯。 ■ 隱私 - 不追蹤、不投放廣告、不販售資料。 - 設定與金鑰只存在你的瀏覽器本機。 - 只有在你按下翻譯時，才會把該段文字送到你選擇的翻譯服務以取得譯文。 讓讀外文像讀母語一樣輕鬆。 Bilingual Reader turns any foreign-language content into easy line-by-line reading — original on one line, translation on the next — so you read faster and pick up the language along the way. Free, no API key required by default. ■ Features - Any webpage: click the toolbar icon → "Translate this page", or press Alt+A — full-page bilingual; do it again to turn off. A general layout detector finds the real body text even on modern sites built with div/span (e.g. Facebook). - X / Twitter & Reddit: automatic bilingual display; press Alt+A (or the button) to hide/show the translation anytime. - YouTube: clean, movie-style bilingual subtitles synced to the audio, one sentence at a time; press Alt+A to switch back to the original captions. - Double-click word popup (optional, off by default): double-click a word or select a phrase on any page to get the original + 🔊 read-aloud + translation in place, with a dictionary card for single words. This feature requests broad host access only when you turn it on, and gives it back when you turn it off. - One-click Traditional / Simplified Chinese. - Multiple translation styles: underline, box, highlight, italic, bold, plus a "learning mode" that blurs the translation until you hover. - Customizable translation color and font size. ■ Translation quality - Uses the page title as background context so product names and proper nouns are less likely to be mistranslated. - Long paragraphs are aligned as a whole, keeping cross-line meaning coherent and easier to read. ■ Engines (always free) - Uses a free engine by default — zero setup, no key. - Two built-in free engines: if Google's free endpoint is occasionally rate-limited, it automatically falls back to Microsoft's free endpoint so translation keeps working. - Optional: add your own Gemini / OpenAI key, or connect a local Ollama server, for higher-quality or fully local translation. ■ Privacy - No tracking, no ads, no data selling. - Settings and keys are stored locally in your browser. - Text is only sent to your chosen translation service when you trigger a translation.