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Building the Tip Calculator App

1. Project Structure:

Your project will typically have the following structure:

Project Root
├── index.html
├── styles.css
└── script.js

2. Frontend:

a. HTML (index.html)

The HTML file houses the structure of your calculator. This includes input fields for the bill amount and tip percentage, and the area where results will be displayed.


<div class="container">
    <h1>Tip Calculator</h1>
    <div class="input-box">
        <label for="bill">Bill Amount:</label>
        <input type="number" id="bill" placeholder="Enter bill amount">
    <div class="input-box">
        <label for="tipPercentage">Tip Percentage:</label>
        <select id="tipPercentage">
            <!-- Various tip percentages as options -->
    <div class="results"></div>

b. CSS (styles.css)

The CSS file styles the calculator. It provides it with a modern look, responsive design, and ensures it’s user-friendly.


.container {
    max-width: 400px;
    background-color: #fff;
    padding: 20px;
    border-radius: 10px;
    /* Other styles... */

3. Functionality:

a. JavaScript (script.js)

This file handles the functionality. It listens for input changes and calculates the tip.


const billElement = document.getElementById('bill');
const tipPercentageElement = document.getElementById('tipPercentage');
const resultsElement = document.querySelector('.results');

billElement.addEventListener('input', calculateTip);
tipPercentageElement.addEventListener('change', calculateTip);

function calculateTip() {
    let bill = parseFloat(billElement.value);
    let tipPercentage = parseFloat(tipPercentageElement.value);
    /* Calculation logic and updating the results */

4. Workflow:

  1. User Interaction: The user starts by entering their bill amount in the provided input field.
  2. Tip Selection: The user selects a desired tip percentage from a dropdown.
  3. Calculation: Once both pieces of information are provided, the app automatically calculates the tip amount and the total bill (including the tip).
  4. Display: The calculated amounts are then displayed to the user in a neatly formatted manner.

5. Deployment:

Once you’ve built and tested your app locally, you can deploy it for public access. In this case, you’ve used GitHub Pages (a great choice for static projects), which provides a live link to share:


Building this Tip Calculator app required a combination of HTML for structure, CSS for styling, and JavaScript for functionality. It serves as a practical tool and an excellent way to consolidate web development skills. It’s a testament to what can be achieved with the foundational trifecta of web technologies.