Lesson 19 of 3358%

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JavaScript
Intermediate
20 min

Changing HTML and CSS

Modify the page dynamically.

Learning Objectives

  • innerHTML, style property

Changing HTML and CSS

Welcome to this lesson on Changing HTML and CSS. JavaScript is the programming language of the web, and changing html and css is a fundamental piece of that ecosystem.

Explanation

When your browser loads a web page, the HTML creates the structure, the CSS creates the style, and JavaScript creates the interactivity. JavaScript can update both HTML and CSS in real-time.

Code Examples

Here is a simple snippet demonstrating this concept:

el.textContent = "New Title";
el.style.color = "red";\n```

### Explanation of Code

In the example above, we define the logic required to implement the concept, and then execute it. The JavaScript engine parses this syntax and runs it.

<Callout type="warning">
**Common Mistake:** Watch out for syntax errors! Missing a bracket or a semicolon can sometimes break your entire script.
</Callout>

### Try It Yourself

Put this into practice! The BrowserCode runtime allows you to execute JavaScript securely in your browser.

<TryItButton />

### Key Takeaways
- JavaScript makes pages interactive.
- Always check your browser console for errors.

Lesson Progress

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