Docs: added Internet content

.github/workflows/lighthouse-report.yml

@@ -42,13 +42,9 @@ jobs:
             http://localhost:3000/tutorial/
             http://localhost:3000/tutorial/category/html/
             http://localhost:3000/tutorial/css/introduction/what-is-css
-            http://localhost:3000/tutorial/javascript/introduction-to-javascript/what-is-js
             http://localhost:3000/tutorial/git/introduction
-            http://localhost:3000/tutorial/category/getting-started-with-github
-            http://localhost:3000/tutorial/github/introduction-to-github
             http://localhost:3000/tutorial/react/react-intro
             http://localhost:3000/tutorial/cybersecurity
-            http://localhost:3000/tutorial/tags
           configPath: ./.github/workflows/lighthouserc.json
           uploadArtifacts: true
           temporaryPublicStorage: true

docs/internet/browser-devtools.mdx

@@ -1 +1,217 @@
-<ComingSoon />
+---
+title: "Browser Developer Tools"
+description: "Learn how to use Browser Developer Tools (DevTools) to inspect, debug, and optimize websites for performance, accessibility, and security."
+tags: [browser, devtools, debugging, chrome, frontend, performance]
+sidebar_label: Browser DevTools
+---
+
+Modern web browsers come with a powerful suite of built-in tools known as **Developer Tools (DevTools)**. These tools help developers **inspect**, **debug**, **analyze**, and **optimize** web applications directly within the browser.
+
+:::info
+Think of DevTools as your web development Swiss Army knife — it provides everything you need to understand how a webpage works under the hood and fix issues on the fly.
+:::
+
+## What Are Browser DevTools?
+
+**Browser DevTools** are a set of debugging tools integrated into browsers like **Chrome**, **Firefox**, **Edge**, and **Safari**. They allow you to view and interact with the **HTML**, **CSS**, **JavaScript**, **network requests**, and **performance metrics** of any webpage.
+
+You can open DevTools by pressing:
+
+* **Windows/Linux:** `Ctrl + Shift + I` or `F12`  
+* **macOS:** `Cmd + Option + I`
+
+## Core Panels in DevTools
+
+Let’s explore the most important panels and their uses:
+
+| Panel | Purpose | Example Use |
+| ------ | -------- | ----------- |
+| **Elements** | Inspect and modify HTML & CSS live | Change a button color or test responsive layout |
+| **Console** | Run JavaScript commands & view logs/errors | `console.log()` debugging |
+| **Network** | Monitor API calls, page load time, and caching | Analyze slow API responses |
+| **Sources** | View and debug JavaScript files with breakpoints | Pause code at runtime |
+| **Performance** | Analyze runtime performance and memory usage | Optimize page rendering |
+| **Application** | View storage, cookies, and service workers | Inspect LocalStorage data |
+| **Security** | Check HTTPS and certificate information | Identify mixed-content issues |
+| **Lighthouse** | Generate audits for performance, SEO, and accessibility | Get site improvement recommendations |
+
+## Elements Panel
+
+The **Elements panel** allows you to explore and edit your website’s structure and styles in real-time.
+
+```mermaid
+graph TD
+  A[HTML Document] --> B[DOM Tree]
+  B --> C[Styles - CSS]
+  C --> D[Rendered Page]
+```
+
+**Example:**
+
+Change the text of a heading directly from the DOM inspector — it won’t affect your source code, but helps test design changes instantly.
+
+
+
+## Console Panel
+
+The **Console** is your **interactive JavaScript terminal**. You can log data, test snippets, or view error messages.
+
+```js title="Console"
+console.log("Hello, CodeHarborHub!");
+```
+
+**Output:**
+
+```
+Hello, CodeHarborHub!
+```
+
+Common uses:
+
+* Debugging JavaScript code  
+* Monitoring warnings or errors  
+* Inspecting objects and variables  
+
+:::tip
+
+You can also use the Console to execute JavaScript on the fly, making it a powerful tool for testing and debugging.
+
+You can also use shortcuts like:
+* `$0` → selects the last inspected element from the Elements panel  
+* `clear()` → clears the console output  
+:::
+
+
+## Network Panel
+
+The **Network panel** shows every HTTP request made by the browser — scripts, images, CSS, APIs, and more.
+
+<Tabs>
+  <TabItem value="what" label="What It Shows" default>
+    * Request and response headers  
+    * File sizes and load times  
+    * Waterfall visualization of loading sequence  
+    * Status codes (e.g., 200, 404, 500)  
+  </TabItem>
+  <TabItem value="why" label="Why It Matters">
+    Helps identify slow resources, failed requests, or caching problems — key for improving **performance** and **user experience**.
+  </TabItem>
+</Tabs>
+
+## Sources Panel
+
+Use the **Sources panel** to:
+* View and debug JavaScript files  
+* Set **breakpoints**  
+* Step through your code  
+* Watch variable values as your script runs  
+
+```jsx live
+function DebugExample() {
+  const [count, setCount] = React.useState(0);
+  return (
+    <div style={{ textAlign: "center" }}>
+      <h3>Debug Counter Example</h3>
+      <p>Count: {count}</p>
+      <button onClick={() => setCount(count + 1)}>Increment</button>
+    </div>
+  );
+}
+```
+
+Try adding a **breakpoint** on the `setCount` line in DevTools to pause execution and inspect the current state.
+
+## Application Panel
+
+The **Application panel** helps manage client-side storage and data.
+
+You can inspect:
+* **Cookies**
+* **LocalStorage** / **SessionStorage**
+* **IndexedDB**
+* **Service Workers**
+* **Cache Storage**
+* **Manifest files**
+
+This is extremely helpful for debugging **PWAs (Progressive Web Apps)** or authentication tokens.
+
+## Performance Panel
+
+The **Performance** tab allows you to **record runtime activity** — useful for diagnosing rendering issues and JavaScript bottlenecks.
+
+Key metrics include:
+* Frame rendering time  
+* Layout and paint events  
+* JavaScript execution time  
+* Memory usage  
+
+```mermaid
+graph LR
+A[User Action] --> B[Script Execution]
+B --> C[Layout Reflow]
+C --> D[Paint]
+D --> E[Composite Layers]
+```
+
+A well-optimized page maintains **60 frames per second (FPS)** for smooth performance.
+
+:::info
+
+Think of the Performance panel as a high-speed camera that captures every millisecond of your webpage’s activity, allowing you to pinpoint exactly where delays occur.
+
+:::
+
+
+## Lighthouse Audits
+
+The **Lighthouse** tool (under the “Audits” or “Lighthouse” panel) evaluates your web app for:
+* Performance  
+* Accessibility  
+* SEO  
+* Progressive Web App (PWA) features  
+
+It provides actionable reports with scores and recommendations.
+
+## Example: Inspecting a Button
+
+```html
+<button class="cta">Click Me</button>
+```
+
+In the **Elements panel**, you can:
+* Modify the color dynamically  
+* Add hover states  
+* Copy computed CSS styles  
+
+Then test the interaction directly without editing the source code.
+
+## Math Behind Load Time (KaTeX Example)
+
+If a page loads 3 MB of data in 6 seconds:
+
+$$
+Load\ Speed = \frac{3\ \text{MB}}{6\ \text{s}} = 0.5\ \text{MB/s}
+$$
+
+Optimizing image size, caching, and lazy loading can drastically reduce this time.
+
+## Best Practices for Using DevTools
+
+* Use **Console logs** for quick debugging, but remove them before production.  
+* Check **Network requests** for unnecessary files or slow APIs.  
+* Run **Lighthouse** regularly for performance improvements.  
+* Monitor **Memory leaks** using the Performance tab.  
+* Use **Responsive Design Mode** to test across devices.  
+
+## Key Takeaways
+
+* DevTools empower you to **inspect, debug, and optimize** web applications.  
+* Mastering key panels (Elements, Console, Network) saves hours of debugging.  
+* Tools like **Lighthouse** and **Performance** enhance web speed and accessibility.  
+* DevTools are your **real-time lab** for frontend development.
+
+:::tip Try It Yourself
+
+Open DevTools on any website and experiment with the panels discussed. Change styles, debug scripts, and analyze network requests to see how they affect the page in real-time!
+
+:::