Quiz App – Mini-Projects

This tutorial will guide you through building a basic quiz app using JavaScript, suitable for intermediate learners. We’ll focus on creating a simple app that allows users to take quizzes and receive feedback. This project will cover fundamental JavaScript concepts like variables, functions, event handling, and basic DOM manipulation. It’s a great starting point for expanding your skills and understanding of web development.

Introduction

A quiz app is a fun and engaging application that tests users’ knowledge on various topics. This tutorial will walk you through building a simple quiz app, incorporating features like question presentation, answer submission, and feedback. It’s a foundational project that will help solidify your understanding of JavaScript and web development principles.

A Quiz App allows users to answer questions and check their score.

Quiz apps are useful because they:

• Test user knowledge
• Improve interaction
• Help learn JavaScript concepts

In this project, users can:

• Answer multiple-choice questions
• Get instant feedback
• See final score

🧠 Concepts You Will Learn

• Arrays and objects
• DOM manipulation
• Event handling
• Conditional logic
• Dynamic UI updates

📌 Features

• Multiple-choice questions
• Next question functionality
• Score tracking
• Final result display

🏗️ Project Setup

You only need:

• A browser
• A code editor

💻 Code Implementation

📁 index.html

<!DOCTYPE html>
<html>
<head>
  <title>Quiz App</title>

  <style>
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
      background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
      min-height: 100vh;
      display: flex;
      justify-content: center;
      align-items: center;
      padding: 20px;
    }

    .quiz-container {
      background: white;
      width: 100%;
      max-width: 500px;
      padding: 40px;
      border-radius: 20px;
      box-shadow: 0 20px 60px rgba(0,0,0,0.3);
      animation: slideIn 0.5s ease-out;
    }

    @keyframes slideIn {
      from {
        opacity: 0;
        transform: translateY(-30px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    h1 {
      color: #667eea;
      margin-bottom: 10px;
      font-size: 2.5em;
      text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
    }

    #question {
      color: #333;
      margin: 25px 0;
      font-size: 1.4em;
      line-height: 1.5;
      min-height: 60px;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    #answers {
      display: flex;
      flex-direction: column;
      gap: 12px;
      margin: 25px 0;
    }

    #answers button {
      padding: 15px 20px;
      border: 2px solid #e0e0e0;
      background: white;
      color: #333;
      border-radius: 10px;
      cursor: pointer;
      font-size: 16px;
      font-weight: 500;
      transition: all 0.3s ease;
      text-align: left;
      position: relative;
      overflow: hidden;
    }

    #answers button:hover:not(:disabled) {
      border-color: #667eea;
      background: #f8f9ff;
      transform: translateX(5px);
      box-shadow: 0 5px 15px rgba(102, 126, 234, 0.2);
    }

    #answers button:disabled {
      cursor: not-allowed;
      opacity: 0.7;
    }

    #answers button.correct {
      background: #d4edda;
      border-color: #27ae60;
      color: #155724;
    }

    #answers button.wrong {
      background: #f8d7da;
      border-color: #e74c3c;
      color: #721c24;
    }

    #nextBtn {
      background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
      color: white;
      padding: 15px 30px;
      border: none;
      border-radius: 10px;
      cursor: pointer;
      font-size: 18px;
      font-weight: 600;
      transition: all 0.3s ease;
      width: 100%;
      margin-top: 20px;
      display: none;
      text-transform: uppercase;
      letter-spacing: 1px;
    }

    #nextBtn:hover {
      transform: translateY(-2px);
      box-shadow: 0 10px 25px rgba(102, 126, 234, 0.4);
    }

    #nextBtn:active {
      transform: translateY(0);
    }

    #score {
      display: none;
      margin-top: 25px;
      padding: 20px;
      background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
      color: white;
      border-radius: 10px;
      font-size: 1.3em;
      font-weight: 600;
      animation: fadeIn 0.5s ease-out;
    }

    @keyframes fadeIn {
      from { opacity: 0; }
      to { opacity: 1; }
    }

    .progress-bar {
      width: 100%;
      height: 8px;
      background: #e0e0e0;
      border-radius: 10px;
      margin: 20px 0;
      overflow: hidden;
    }

    .progress-fill {
      height: 100%;
      background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
      border-radius: 10px;
      transition: width 0.5s ease;
    }
  </style>
</head>
<body>

  <div class="quiz-container">

    <h1>🧠 Quiz App</h1>

    <div class="progress-bar">
      <div class="progress-fill" id="progressBar"></div>
    </div>

    <h2 id="question">Question</h2>

    <div id="answers"></div>

    <button id="nextBtn">Next Question →</button>

    <h3 id="score"></h3>

  </div>

  <script src="script.js"></script>

</body>
</html>

📁 index.html

const quizData = [
  {
    question: "What is the capital of France?",
    options: ["Berlin", "Paris", "Rome", "Madrid"],
    correct: "Paris"
  },
  {
    question: "Which planet is largest?",
    options: ["Mars", "Jupiter", "Venus", "Earth"],
    correct: "Jupiter"
  },
  {
    question: "Which language runs in browser?",
    options: ["Python", "C++", "JavaScript", "Java"],
    correct: "JavaScript"
  },
  {
    question: "What is 12 × 8?",
    options: ["80", "96", "108", "72"],
    correct: "96"
  },
  {
    question: "Who wrote 'Romeo and Juliet'?",
    options: ["William Shakespeare", "Charles Dickens", "J.K. Rowling", "Mark Twain"],
    correct: "William Shakespeare"
  },
  {
    question: "Which element has the chemical symbol 'O'?",
    options: ["Gold", "Oxygen", "Osmium", "Iron"],
    correct: "Oxygen"
  },
  {
    question: "What year did the first man land on the moon?",
    options: ["1969", "1959", "1975", "1982"],
    correct: "1969"
  }
];

let currentQuestion = 0;
let score = 0;
let answered = false;

const questionEl = document.getElementById("question");
const answersEl = document.getElementById("answers");
const nextBtn = document.getElementById("nextBtn");
const scoreEl = document.getElementById("score");
const progressBar = document.getElementById("progressBar");

// Load question
function loadQuestion() {
  answered = false;
  const currentQuiz = quizData[currentQuestion];

  questionEl.textContent = currentQuiz.question;
  answersEl.innerHTML = "";
  nextBtn.style.display = "none";
  scoreEl.style.display = "none";

  // Update progress bar
  const progress = ((currentQuestion) / quizData.length) * 100;
  progressBar.style.width = progress + "%";

  currentQuiz.options.forEach(option => {
    const button = document.createElement("button");
    button.textContent = option;

    button.addEventListener("click", function() {
      if (!answered) {
        checkAnswer(option, button);
      }
    });

    answersEl.appendChild(button);
  });
}

// Check answer
function checkAnswer(selected, button) {
  answered = true;
  const correctAnswer = quizData[currentQuestion].correct;
  const buttons = answersEl.querySelectorAll("button");

  // Disable all buttons and show correct answer
  buttons.forEach(btn => {
    btn.disabled = true;
    if (btn.textContent === correctAnswer) {
      btn.classList.add("correct");
    }
  });

  // Show feedback
  if (selected === correctAnswer) {
    score++;
    button.classList.add("correct");
  } else {
    button.classList.add("wrong");
  }

  nextBtn.style.display = "block";
}

// Next question
nextBtn.addEventListener("click", function() {

  currentQuestion++;

  if (currentQuestion < quizData.length) {

    loadQuestion();

  } else {

    showScore();

  }

});

// Show score
function showScore() {
  // Complete the progress bar
  progressBar.style.width = "100%";

  questionEl.textContent = "🎉 Quiz Completed!";
  answersEl.innerHTML = "";

  nextBtn.style.display = "none";

  const percentage = (score / quizData.length) * 100;
  let emoji = "🏆";
  if (percentage < 50) emoji = "💪";
  else if (percentage < 100) emoji = "🌟";

  scoreEl.innerHTML = `
    ${emoji} Your Score: ${score} / ${quizData.length}<br>
    <span style="font-size: 0.8em; opacity: 0.9;">${percentage.toFixed(0)}% Correct</span>
  `;
  scoreEl.style.display = "block";
}

// Initial load
loadQuestion();

nextBtn.style.display = "none";

Quiz App Tutorial

▶️ How to Run

1. Create a folder
2. Add:
   • index.html
   • script.js
3. Open index.html in browser

⚙️ How It Works

• Questions stored in an array of objects
• loadQuestion() updates the UI
• Answer buttons are created dynamically
• checkAnswer() validates the selected answer
• Score is tracked using a variable

Summary

This tutorial has provided a basic introduction to building a quiz app using JavaScript. By understanding fundamental concepts like variables, functions, and event handling, you’ve laid a solid foundation for further exploration and development of more complex web applications. Remember to practice and experiment with different features to truly master the skills you’ve learned.