feat: Add full in-page search functionality

Completed Phase 1 high priority task - comprehensive search system:

Search Features:
- Press '/' to enter search mode with dedicated search input
- Case-insensitive search across all content
- Enter to execute search and find all matches
- Real-time match highlighting:
  * Yellow background = current match
  * Blue background = other matches
- Navigate results with 'n' (next) and 'N' (previous)
- Smart scrolling - auto-scroll to current match
- Match counter in status bar (e.g., "Match 3/10")
- Esc to cancel search input
- Search state clears when loading new pages

Implementation Details:
- Added search state to MainWindow::Impl
  * search_mode, search_query, search_matches, current_match
- Search input component (similar to address bar)
- executeSearch() - finds all matching lines
- nextMatch()/previousMatch() - cycle through results
- Content renderer highlights matches dynamically
- Status panel shows search results with emoji indicator

User Experience:
- Intuitive vim-style '/' to search
- Visual feedback with color highlighting
- Match position indicator in status
- Non-intrusive - doesn't interfere with navigation
- Seamless integration with existing UI

Keyboard shortcuts:
- /: Start search
- Enter: Execute search
- n: Next match
- N: Previous match
- Esc: Cancel search

Documentation:
- Updated KEYBOARD.md with search section and usage example
- Updated STATUS.md to reflect completion
- Added search to interactive features list

The browser now has powerful in-page search! 🔍✅

KEYBOARD.md

@@ -60,6 +60,18 @@
 # 4. Press 'Esc' to cancel
 ```
 
+### In-Page Search
+```bash
+# Search for text on current page
+# 1. Press '/' to open search bar
+# 2. Type your search query (case-insensitive)
+# 3. Press 'Enter' to find all matches
+# 4. Press 'n' to go to next match
+# 5. Press 'N' to go to previous match
+# 6. Matches are highlighted (yellow = current, blue = other matches)
+# 7. Status bar shows "Match X/Y" count
+```
+
 ## 🎨 UI Elements
 
 ### Top Bar
@@ -93,16 +105,22 @@
 4. **Efficient Browsing**: Use `g` to jump to top, `G` to jump to bottom
 5. **Address Bar**: Type `o` quickly to enter a new URL
 
+### Search
+| Key | Action |
+|-----|--------|
+| `/` | Start search (type query and press Enter) |
+| `n` | Next search result |
+| `N` | Previous search result |
+| `Esc` | Cancel search |
+
 ## 🐛 Known Limitations
 
 - Ctrl+L not yet working for address bar (use 'o' instead)
-- No search functionality yet (/ key)
 - No bookmarks yet (Ctrl+D)
 - No history panel yet (F3)
 
 ## 🚀 Coming Soon
 
-- [ ] In-page search (`/` to search, `n`/`N` to navigate results)
 - [ ] Bookmarks (add, remove, list)
 - [ ] History (view and navigate)
 - [ ] Better link highlighting

STATUS.md

@@ -35,8 +35,9 @@
   - **Link Navigation** - Tab, number keys (1-9), Enter to follow
   - **Address Bar** - 'o' to open, type URL, Enter to navigate
   - **Browser Controls** - Backspace to go back, 'f' to go forward, r/F5 to refresh
-  - **Real-time Status** - Load stats, scroll position, selected link
+  - **In-Page Search** - '/' to search, n/N to navigate results, highlighted matches
-  - **Visual Feedback** - Navigation button states, link highlighting
+  - **Real-time Status** - Load stats, scroll position, selected link, search results
+  - **Visual Feedback** - Navigation button states, link highlighting, search highlighting
 
 ### Build & Deployment
 - ✅ Binary size: **827KB** (well under 1MB target!)
@@ -58,11 +59,6 @@
   - No visual history panel (F3)
   - No persistence across sessions
 
-- ⚠️ **Search** - Not implemented
-  - / search command not working
-  - n/N navigation not working
-  - No highlight of matches
-
 ### Feature Gaps
 - ⚠️ No form support (input fields, buttons, etc.)
 - ⚠️ No image rendering (even ASCII art)
@@ -72,18 +68,14 @@
 ## 🎯 Next Steps Priority
 
 ### Phase 1: Enhanced UX (High Priority)
-4. **Implement Search** (src/ui/content_view.cpp)
-   - Add / to start search
-   - Highlight matches
-   - n/N to navigate results
 
-5. **Add Bookmark System** (new files)
+1. **Add Bookmark System** (new files)
    - Implement bookmark storage (JSON file)
    - Create bookmark panel UI
    - Add Ctrl+D to bookmark
    - F2 to view bookmarks
 
-6. **Add History** (new files)
+2. **Add History** (new files)
    - Implement history storage (JSON file)
    - Create history panel UI
    - F3 to view history
@@ -122,6 +114,8 @@ Interactive test:
 ✅ Enter to follow link - WORKS
 ✅ Backspace to go back - WORKS
 ✅ 'f' to go forward - WORKS
+✅ '/' to search - WORKS
+✅ 'n'/'N' to navigate search results - WORKS
 ✅ 'r' to refresh - WORKS
 ✅ 'o' to open address bar - WORKS
 ```

src/ui/main_window.cpp

@@ -12,6 +12,7 @@
 
 #include <sstream>
 #include <algorithm>
+#include <cctype>
 
 namespace tut {
 
@@ -40,6 +41,12 @@ public:
     // Split content into lines for scrolling
     std::vector<std::string> content_lines_;
 
+    // Search state
+    bool search_mode_{false};
+    std::string search_query_;
+    std::vector<int> search_matches_;  // Line indices with matches
+    int current_match_{-1};  // Index into search_matches_
+
     void setContent(const std::string& content) {
         content_lines_.clear();
         std::istringstream iss(content);
@@ -48,6 +55,12 @@ public:
             content_lines_.push_back(line);
         }
         scroll_offset_ = 0;
+
+        // Clear search state when new content is loaded
+        search_mode_ = false;
+        search_query_.clear();
+        search_matches_.clear();
+        current_match_ = -1;
     }
 
     void scrollDown(int lines = 1) {
@@ -79,6 +92,54 @@ public:
             selected_link_ = static_cast<int>(links_.size()) - 1;
         }
     }
+
+    void executeSearch() {
+        search_matches_.clear();
+        current_match_ = -1;
+
+        if (search_query_.empty()) {
+            return;
+        }
+
+        // Convert search query to lowercase for case-insensitive search
+        std::string query_lower = search_query_;
+        std::transform(query_lower.begin(), query_lower.end(), query_lower.begin(), ::tolower);
+
+        // Find all lines containing the search query
+        for (size_t i = 0; i < content_lines_.size(); ++i) {
+            std::string line_lower = content_lines_[i];
+            std::transform(line_lower.begin(), line_lower.end(), line_lower.begin(), ::tolower);
+
+            if (line_lower.find(query_lower) != std::string::npos) {
+                search_matches_.push_back(static_cast<int>(i));
+            }
+        }
+
+        if (!search_matches_.empty()) {
+            current_match_ = 0;
+            // Scroll to first match
+            scroll_offset_ = search_matches_[0];
+        }
+    }
+
+    void nextMatch() {
+        if (search_matches_.empty()) return;
+
+        current_match_ = (current_match_ + 1) % static_cast<int>(search_matches_.size());
+        // Scroll to the match
+        scroll_offset_ = search_matches_[current_match_];
+    }
+
+    void previousMatch() {
+        if (search_matches_.empty()) return;
+
+        current_match_--;
+        if (current_match_ < 0) {
+            current_match_ = static_cast<int>(search_matches_.size()) - 1;
+        }
+        // Scroll to the match
+        scroll_offset_ = search_matches_[current_match_];
+    }
 };
 
 MainWindow::MainWindow() : impl_(std::make_unique<Impl>()) {}
@@ -99,6 +160,11 @@ int MainWindow::run() {
     auto address_input = Input(&address_content, "Enter URL...");
     bool address_focused = false;
 
+    // 搜索输入
+    std::string search_content;
+    auto search_input = Input(&search_content, "Search...");
+    bool search_focused = false;
+
     // 内容渲染器
     auto content_renderer = Renderer([this] {
         Elements lines;
@@ -115,7 +181,28 @@ int MainWindow::run() {
                           static_cast<int>(impl_->content_lines_.size()));
 
         for (int i = start; i < end; i++) {
-            lines.push_back(text(impl_->content_lines_[i]));
+            // Check if this line is a search match
+            bool is_match = false;
+            bool is_current_match = false;
+
+            if (!impl_->search_matches_.empty()) {
+                auto it = std::find(impl_->search_matches_.begin(),
+                                  impl_->search_matches_.end(), i);
+                if (it != impl_->search_matches_.end()) {
+                    is_match = true;
+                    int match_index = std::distance(impl_->search_matches_.begin(), it);
+                    is_current_match = (match_index == impl_->current_match_);
+                }
+            }
+
+            // Render line with appropriate highlighting
+            auto line_element = text(impl_->content_lines_[i]);
+            if (is_current_match) {
+                line_element = line_element | bgcolor(Color::Yellow) | color(Color::Black);
+            } else if (is_match) {
+                line_element = line_element | bgcolor(Color::Blue) | color(Color::White);
+            }
+            lines.push_back(line_element);
         }
 
         // Scroll indicator
@@ -135,7 +222,16 @@ int MainWindow::run() {
     auto status_panel = Renderer([this] {
         Elements status_items;
 
-        if (impl_->loading_) {
+        // Search status takes priority
+        if (!impl_->search_matches_.empty()) {
+            std::string search_info = "🔍 Match " +
+                                     std::to_string(impl_->current_match_ + 1) + "/" +
+                                     std::to_string(impl_->search_matches_.size()) +
+                                     " for \"" + impl_->search_query_ + "\"";
+            status_items.push_back(text(search_info) | color(Color::Yellow));
+        } else if (impl_->search_mode_ && !impl_->search_query_.empty()) {
+            status_items.push_back(text("🔍 No matches for \"" + impl_->search_query_ + "\"") | dim);
+        } else if (impl_->loading_) {
             status_items.push_back(text("⏳ Loading...") | dim);
         } else if (impl_->load_time_ > 0) {
             std::string stats = "⬇ " + std::to_string(impl_->load_bytes_ / 1024) + " KB  " +
@@ -146,7 +242,8 @@ int MainWindow::run() {
             status_items.push_back(text("Ready") | dim);
         }
 
-        if (impl_->selected_link_ >= 0 && impl_->selected_link_ < static_cast<int>(impl_->links_.size())) {
+        if (impl_->selected_link_ >= 0 && impl_->selected_link_ < static_cast<int>(impl_->links_.size()) &&
+            impl_->search_matches_.empty()) {
             status_items.push_back(separator());
             std::string link_info = "[" + std::to_string(impl_->selected_link_ + 1) + "] " +
                                    impl_->links_[impl_->selected_link_].url;
@@ -158,9 +255,18 @@ int MainWindow::run() {
 
     // 主布局
     auto main_renderer = Renderer([&] {
-        return vbox({
+        Elements top_bar_elements;
-            // 顶部栏
+
-            hbox({
+        if (search_focused) {
+            // Show search bar when in search mode
+            top_bar_elements.push_back(hbox({
+                text("🔍 "),
+                search_input->Render() | flex | border | focus,
+                text(" [Esc to cancel]") | dim,
+            }));
+        } else {
+            // Normal address bar
+            top_bar_elements.push_back(hbox({
                 text(impl_->can_go_back_ ? "[◀]" : "[◀]") | (impl_->can_go_back_ ? bold : dim),
                 text(" "),
                 text(impl_->can_go_forward_ ? "[▶]" : "[▶]") | (impl_->can_go_forward_ ? bold : dim),
@@ -172,7 +278,12 @@ int MainWindow::run() {
                 text("[⚙]") | bold,
                 text(" "),
                 text("[?]") | bold,
-            }),
+            }));
+        }
+
+        return vbox({
+            // 顶部栏
+            vbox(top_bar_elements),
             separator(),
             // 内容区
             content_renderer->Render() | flex,
@@ -235,11 +346,44 @@ int MainWindow::run() {
             return true;
         }
 
-        // Don't handle other keys if address bar is focused
+        // Search mode activation
-        if (address_focused) {
+        if (event == Event::Character('/') && !address_focused && !search_focused) {
+            search_focused = true;
+            search_content.clear();
+            return true;
+        }
+
+        // Execute search
+        if (event == Event::Return && search_focused) {
+            impl_->search_mode_ = true;
+            impl_->search_query_ = search_content;
+            impl_->executeSearch();
+            search_focused = false;
+            return true;
+        }
+
+        // Exit search mode
+        if (event == Event::Escape && search_focused) {
+            search_focused = false;
+            search_content.clear();
+            return true;
+        }
+
+        // Don't handle other keys if address bar or search is focused
+        if (address_focused || search_focused) {
             return false;
         }
 
+        // Navigate search results (only when not in input mode)
+        if (event == Event::Character('n') && !impl_->search_matches_.empty()) {
+            impl_->nextMatch();
+            return true;
+        }
+        if (event == Event::Character('N') && !impl_->search_matches_.empty()) {
+            impl_->previousMatch();
+            return true;
+        }
+
         // Scrolling
         if (event == Event::Character('j') || event == Event::ArrowDown) {
             impl_->scrollDown(1);