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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

Add Packages

Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.

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HTML
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CSS
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JS 

              
                ///////////////////////Exercises /////////////////////////
// 1. Declare the variables x, y, and z, and set them equal to 13, 27, and 94

// 2. Print the sum of all three variables to the console, and using your knowledge of string concatenation, print the statement "The sum of x, y, and z is ", followed by the sum, all on one line.

// 3. Write the difference between z and y, divided by x to the webpage in the format "The difference between z and y, divided by x is _____" where the blank is the value.

// 4. Declare a new variable named 'age' and set it equal to your age. Increment this variable by 1 on the next line, and on a third line, print the variable to the console. 

// 5. Print the age variable to the console in this format: "In one year I will be ___" where the blank is the value of your age.

//////////////Extra Exercises: 

//1. Create a variable and set it equal to a number of your choice. Create another variable and set it equal to another number of your choice. 

//2. Calculate the first variable multiplied by the second variable, and print the answer to the console. 

//3. Below that, calculate the first variable divided by the second variable, and print it to the console. 

//4. Calculate the fist variable multiplied by (the second variable divided by the first variable) and print it to the console. 

//5. Print the second variable with increment to the console.
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Console