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HTML

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Insecure Resource

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CSS

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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

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Vendor Prefixing

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JavaScript

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

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Babel includes JSX processing.

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Packages

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HTML 

              
                <p>Submit the form then check the console.</p>

<form>
  <p>
    <label for="name">Name</label>
    <input type="text" name="name" id="name" value="Mario">
  </p>
  <p>
    <label for="email">Email</label>
    <input type="email" name="email" id="email" value="mario@nintendo.com">
  </p>
  <p>
    <label for="message">Message</label>
    <textarea name="message" id="message">Mamma Mia!</textarea>
  </p>
  <p>
    <button type="submit">Submit</button>
  </p>
</form>
!

CSS 

              
                * {
  box-sizing: border-box;
}

body {
  width: 88%;
  max-width: 30em;
  margin: 1em auto;
  line-height: 1.5;
  font-family: Arial, sans-serif;
}

label, input, textarea {
  display: block;
}

input, textarea, button {
  font: inherit;
}

input, textarea {
  width: 100%;
}

#output {
  font-family: monospace;
}
!

JS 

              
                //
// Variables
//

// Get the form element
const form = document.querySelector('form');


//
// Functions
//

/**
 * Serialize all form data into a query string
 * {@link https://gist.github.com/kieranbarker/bb7c54bd12156c069419f64a22e61552}
 * @param {HTMLFormElement} form The form
 * @returns {String} The query string
 */
function serialize (form) {
  // Create a new FormData object
  const formData = new FormData(form);

  // Create a new URLSearchParams object
  const params = new URLSearchParams(formData);

  // Return the query string
  return params.toString();
}

/**
 * Handle submit events
 * @param {Event} event The Event interface
 */
function handleSubmit (event) {
  // Prevent the default submission
  event.preventDefault();

  // Log the query string
  console.log(serialize(this));

  // Alert the user
  alert('Check the console.');
}


//
// Inits & Event Listeners
//

// Handle submit events
form.addEventListener('submit', handleSubmit);
!
999px

Console