Force Dark Mode - ThemeSwitcher

Apply smart dark mode to websites, PDFs, and documents with Auto, CSS, Invert, native dark detection, and local PDF rendering.

Force Dark Mode - ThemeSwitcher transforms websites, PDFs, and local documents into a soothing, eye-friendly dark theme with intelligent engine selection and customizable color palettes. Unlike simple global inverters that break photos, video thumbnails, and page layouts, ThemeSwitcher analyzes each webpage's structure and luminance to apply the optimal dark strategy automatically. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ KEY FEATURES ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ✦ Intelligent Auto Engine: Dynamically samples page elements, luminance, and media density. If a site natively supports dark mode (such as YouTube or GitHub in night mode), ThemeSwitcher automatically respects it and avoids double inversion. ✦ Layout-Safe CSS Engine: Recolors backgrounds, typography, forms, and borders using mathematical contrast calculations while preserving images, videos, and canvas elements. Black brand logos on dark backgrounds are automatically detected and inverted for clarity. ✦ Smart Invert Engine: Protected color inversion with re-inversion for media, perfect for complex graphics-heavy pages and specialized web applications. ✦ Local PDF & Document Reader: Open online and local PDFs, Markdown (.md), TXT, and RTF documents in a built-in dark reader. Powered by bundled PDF.js with saturation-aware canvas pixel conversion—diagrams and text stay crisp without uploading confidential files to external servers. ✦ Per-Site Custom Background Colors: Choose between pitch black (#000000) for OLED displays or a soft midnight slate (#0f1115) from the popup. Surfaces and borders adapt automatically to guarantee WCAG AA contrast. ✦ Zero White Flashes: Applied at document_start before the DOM renders to protect your eyes from blinding white flashes between page navigations. ✦ Instant Toggle: Switch dark mode on or off instantly with a single click—no page reloads required. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ HOW TO USE IT ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1. Click the ThemeSwitcher icon in your browser toolbar on any website. 2. Toggle dark mode on or off with a single click. 3. Switch between Auto, CSS, or Invert engines, or pick a custom background color for the current domain. 4. Click "Open file viewer" to open any local or online PDF in dark mode. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 100% PRIVATE & OFFLINE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ThemeSwitcher is built with an uncompromising commitment to privacy: • Zero analytics, telemetry, or tracking pixels. • Zero external network calls—runs 100% locally in your browser. • No browsing history or website URLs ever leave your computer. • Preferences sync strictly through your personal Google Account via chrome.storage.sync. • Fully open-source under the MIT License for public security auditing. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ SUPPORT & RESOURCES ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Website: https://darkmode.pshah.fun/ Support & Feedback: https://darkmode.pshah.fun/support.html Help & Guides: https://darkmode.pshah.fun/how-it-works.html