✨ The Prompt Phrase
node

💻 Code Preview

📦 All-in-One Code
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>⬢ Node.js & REPL Master Guide</title>
  <link href="https://fonts.googleapis.com/css2?family=Poppins:wght@400;600;700;800&family=Fira+Code:wght@400;500&display=swap" rel="stylesheet">
  <style>
    * { margin: 0; padding: 0; box-sizing: border-box; }
    
    :root {
      --node: #68a063;
      --cyan: #06b6d4;
      --purple: #8b5cf6;
      --pink: #ec4899;
      --orange: #f97316;
      --yellow: #fbbf24;
      --blue: #3b82f6;
      --green: #10b981;
      --red: #ef4444;
      --bg: #0a0e1a;
      --card: #151b2e;
      --text: #e2e8f0;
    }

    body {
      font-family: 'Poppins', sans-serif;
      background: var(--bg);
      color: var(--text);
      min-height: 100vh;
      overflow-x: hidden;
    }

    /* Animated background */
    .bg-animation {
      position: fixed;
      inset: 0;
      z-index: -1;
      overflow: hidden;
    }

    .float-symbol {
      position: absolute;
      font-size: 3rem;
      opacity: 0.08;
      font-family: 'Fira Code', monospace;
      animation: symbolFloat 20s infinite ease-in-out;
      color: var(--node);
    }

    @keyframes symbolFloat {
      0%, 100% { transform: translate(0, 0) rotate(0deg); }
      25% { transform: translate(100px, -100px) rotate(90deg); }
      50% { transform: translate(200px, 50px) rotate(180deg); }
      75% { transform: translate(-50px, 150px) rotate(270deg); }
    }

    .orb {
      position: absolute;
      border-radius: 50%;
      filter: blur(120px);
      opacity: 0.15;
      animation: orbMove 30s ease-in-out infinite;
    }

    @keyframes orbMove {
      0%, 100% { transform: translate(0, 0) scale(1); }
      50% { transform: translate(100px, -100px) scale(1.3); }
    }

    /* Progress bar */
    .progress {
      position: fixed;
      top: 0;
      left: 0;
      height: 4px;
      background: linear-gradient(90deg, var(--node), var(--cyan), var(--purple), var(--pink));
      z-index: 1000;
      transition: width 0.2s;
    }

    /* Header */
    header {
      text-align: center;
      padding: 70px 20px 50px;
      position: relative;
    }

    .logo-container {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 25px;
      margin-bottom: 35px;
      flex-wrap: wrap;
    }

    .node-logo {
      width: 110px;
      height: 110px;
      background: linear-gradient(135deg, var(--node), var(--green));
      border-radius: 24px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 3.5rem;
      cursor: pointer;
      transition: all 0.3s;
      box-shadow: 0 20px 60px rgba(104, 160, 99, 0.4);
      animation: logoFloat 4s ease-in-out infinite;
      position: relative;
      overflow: hidden;
    }

    @keyframes logoFloat {
      0%, 100% { transform: translateY(0) rotate(0deg); }
      50% { transform: translateY(-20px) rotate(5deg); }
    }

    .node-logo::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(45deg, transparent, rgba(255,255,255,0.3), transparent);
      animation: logoShine 3s infinite;
    }

    @keyframes logoShine {
      0% { transform: translateX(-100%) rotate(45deg); }
      100% { transform: translateX(200%) rotate(45deg); }
    }

    .node-logo:hover {
      transform: scale(1.15) rotate(10deg);
      box-shadow: 0 30px 80px rgba(104, 160, 99, 0.6);
    }

    .repl-demo {
      background: rgba(6, 182, 212, 0.1);
      border: 2px solid var(--cyan);
      border-radius: 14px;
      padding: 15px 25px;
      font-family: 'Fira Code', monospace;
      font-size: 0.9rem;
      animation: replPulse 3s ease-in-out infinite;
    }

    @keyframes replPulse {
      0%, 100% { transform: scale(1); box-shadow: 0 0 20px rgba(6, 182, 212, 0.3); }
      50% { transform: scale(1.05); box-shadow: 0 0 40px rgba(6, 182, 212, 0.5); }
    }

    h1 {
      font-size: clamp(2rem, 6vw, 3.5rem);
      font-weight: 800;
      background: linear-gradient(135deg, var(--node), var(--cyan), var(--purple));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 18px;
      line-height: 1.2;
    }

    .subtitle {
      color: #64748b;
      font-size: 1.2rem;
      max-width: 700px;
      margin: 0 auto;
    }

    /* Main container */
    main {
      max-width: 1100px;
      margin: 0 auto;
      padding: 20px;
    }

    .section {
      margin-bottom: 55px;
      opacity: 0;
      transform: translateY(50px);
      transition: all 0.8s ease-out;
    }

    .section.vis {
      opacity: 1;
      transform: translateY(0);
    }

    .sec-title {
      display: flex;
      align-items: center;
      gap: 18px;
      font-size: 1.7rem;
      font-weight: 700;
      margin-bottom: 22px;
    }

    .sec-icon {
      width: 56px;
      height: 56px;
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.6rem;
      animation: iconWobble 3s ease-in-out infinite;
    }

    @keyframes iconWobble {
      0%, 100% { transform: rotate(-5deg) scale(1); }
      50% { transform: rotate(5deg) scale(1.1); }
    }

    /* Cards */
    .card {
      background: var(--card);
      border-radius: 22px;
      padding: 32px;
      margin-bottom: 24px;
      border: 1px solid rgba(255,255,255,0.08);
      transition: all 0.3s;
      position: relative;
      overflow: hidden;
    }

    .card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 5px;
      background: linear-gradient(90deg, var(--node), var(--cyan), var(--purple));
    }

    .card:hover {
      transform: translateY(-8px);
      box-shadow: 0 30px 70px rgba(0,0,0,0.4);
      border-color: var(--cyan);
    }

    .card h3 {
      color: var(--cyan);
      margin-bottom: 18px;
      font-size: 1.4rem;
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .card p {
      color: #94a3b8;
      line-height: 1.9;
      margin-bottom: 16px;
    }

    /* Featured card */
    .featured {
      background: linear-gradient(135deg, rgba(104, 160, 99, 0.15), rgba(6, 182, 212, 0.15));
      border: 2px solid var(--node);
    }

    .featured-badge {
      position: absolute;
      top: -14px;
      right: 30px;
      background: linear-gradient(135deg, var(--orange), var(--yellow));
      color: #000;
      padding: 7px 20px;
      border-radius: 22px;
      font-size: 0.75rem;
      font-weight: 700;
      animation: badgePulse 2s ease-in-out infinite;
    }

    @keyframes badgePulse {
      0%, 100% { box-shadow: 0 0 20px rgba(249, 115, 22, 0.5); }
      50% { box-shadow: 0 0 40px rgba(249, 115, 22, 0.8); }
    }

    /* Code blocks */
    .code-block {
      background: #0a0f1a;
      border-radius: 18px;
      overflow: hidden;
      margin: 22px 0;
      border: 1px solid rgba(255,255,255,0.08);
      box-shadow: 0 15px 45px rgba(0,0,0,0.4);
    }

    .code-header {
      background: rgba(0,0,0,0.4);
      padding: 16px 22px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .code-dots {
      display: flex;
      gap: 8px;
    }

    .dot {
      width: 13px;
      height: 13px;
      border-radius: 50%;
      cursor: pointer;
      transition: all 0.2s;
    }

    .dot:hover { transform: scale(1.4); }
    .dot.r { background: #ff5f56; }
    .dot.y { background: #ffbd2e; }
    .dot.g { background: #27ca40; }

    .code-lang {
      color: var(--cyan);
      font-size: 0.9rem;
      font-weight: 600;
      font-family: 'Fira Code', monospace;
    }

    .code-copy {
      background: rgba(255,255,255,0.1);
      border: none;
      padding: 8px 18px;
      border-radius: 8px;
      color: var(--text);
      cursor: pointer;
      font-size: 0.85rem;
      transition: all 0.3s;
      font-weight: 600;
    }

    .code-copy:hover { 
      background: var(--cyan); 
      transform: translateY(-2px);
      color: #000;
    }

    .code-copy.copied { background: var(--green); }

    .code-body {
      padding: 24px;
      font-family: 'Fira Code', monospace;
      font-size: 0.9rem;
      line-height: 2;
      overflow-x: auto;
    }

    .kw { color: var(--purple); }
    .str { color: var(--yellow); }
    .num { color: var(--orange); }
    .func { color: var(--cyan); }
    .comment { color: #6b7280; font-style: italic; }
    .var { color: var(--pink); }
    .prop { color: var(--green); }

    /* Interactive REPL */
    .repl-container {
      background: linear-gradient(135deg, rgba(6, 182, 212, 0.1), rgba(139, 92, 246, 0.1));
      border-radius: 22px;
      padding: 35px;
      border: 2px solid rgba(6, 182, 212, 0.3);
      margin: 28px 0;
    }

    .repl-title {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--yellow);
      margin-bottom: 22px;
      text-align: center;
    }

    .terminal {
      background: #0a0f1a;
      border-radius: 16px;
      overflow: hidden;
      margin: 22px 0;
      box-shadow: 0 20px 60px rgba(0,0,0,0.5);
    }

    .term-header {
      background: rgba(0,0,0,0.4);
      padding: 14px 22px;
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .term-title {
      flex: 1;
      text-align: center;
      color: #64748b;
      font-size: 0.9rem;
      font-weight: 600;
    }

    .term-body {
      padding: 24px;
      font-family: 'Fira Code', monospace;
      font-size: 0.9rem;
      min-height: 200px;
      max-height: 500px;
      overflow-y: auto;
    }

    .term-line { 
      margin-bottom: 10px;
      animation: lineAppear 0.3s ease-out;
    }

    @keyframes lineAppear {
      from { opacity: 0; transform: translateX(-10px); }
      to { opacity: 1; transform: translateX(0); }
    }

    .prompt { 
      color: var(--node); 
      font-weight: 600;
      text-shadow: 0 0 10px rgba(104, 160, 99, 0.5);
    }

    .cursor {
      display: inline-block;
      width: 10px;
      height: 20px;
      background: var(--cyan);
      animation: blink 1s infinite;
      vertical-align: middle;
      margin-left: 2px;
    }

    @keyframes blink {
      0%, 50% { opacity: 1; }
      51%, 100% { opacity: 0; }
    }

    /* Command buttons */
    .cmd-buttons {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
      gap: 14px;
      margin: 22px 0;
    }

    .cmd-btn {
      background: var(--card);
      padding: 18px;
      border-radius: 14px;
      border: 2px solid rgba(255,255,255,0.1);
      cursor: pointer;
      transition: all 0.3s;
      text-align: center;
    }

    .cmd-btn:hover {
      border-color: var(--cyan);
      background: rgba(6, 182, 212, 0.1);
      transform: translateY(-5px);
    }

    .cmd-btn-icon {
      font-size: 2rem;
      margin-bottom: 10px;
    }

    .cmd-btn-title {
      color: var(--cyan);
      font-weight: 600;
      margin-bottom: 6px;
    }

    .cmd-btn-desc {
      color: #64748b;
      font-size: 0.85rem;
    }

    /* Steps */
    .steps {
      display: flex;
      flex-direction: column;
      gap: 18px;
    }

    .step {
      display: flex;
      gap: 20px;
      padding: 24px;
      background: rgba(255,255,255,0.02);
      border-radius: 16px;
      border: 1px solid rgba(255,255,255,0.06);
      cursor: pointer;
      transition: all 0.3s;
    }

    .step:hover {
      transform: translateX(12px);
      border-color: var(--node);
      background: rgba(104, 160, 99, 0.1);
    }

    .step-num {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--node), var(--cyan));
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      flex-shrink: 0;
      font-size: 1.2rem;
      box-shadow: 0 8px 25px rgba(104, 160, 99, 0.4);
    }

    .step-content h4 { 
      margin-bottom: 8px; 
      color: var(--text); 
      font-size: 1.1rem;
    }

    .step-content p { 
      color: #64748b; 
      font-size: 0.95rem; 
      margin: 0;
      line-height: 1.6;
    }

    /* Info boxes */
    .info {
      padding: 22px;
      border-radius: 16px;
      margin: 20px 0;
      display: flex;
      gap: 16px;
      align-items: flex-start;
    }

    .info.tip {
      background: rgba(104, 160, 99, 0.12);
      border-left: 4px solid var(--node);
    }

    .info.warn {
      background: rgba(251, 191, 36, 0.12);
      border-left: 4px solid var(--yellow);
    }

    .info.important {
      background: rgba(139, 92, 246, 0.12);
      border-left: 4px solid var(--purple);
    }

    .info.cool {
      background: rgba(6, 182, 212, 0.12);
      border-left: 4px solid var(--cyan);
    }

    .info-icon { 
      font-size: 1.5rem; 
      flex-shrink: 0;
      animation: iconBounce 2s ease-in-out infinite;
    }

    @keyframes iconBounce {
      0%, 100% { transform: translateY(0); }
      50% { transform: translateY(-5px); }
    }

    /* Comparison table */
    .comparison {
      overflow-x: auto;
      margin: 24px 0;
    }

    .comparison table {
      width: 100%;
      border-collapse: collapse;
      background: var(--card);
      border-radius: 16px;
      overflow: hidden;
    }

    .comparison th {
      background: rgba(6, 182, 212, 0.2);
      padding: 18px;
      text-align: left;
      color: var(--cyan);
      font-weight: 600;
    }

    .comparison td {
      padding: 18px;
      border-top: 1px solid rgba(255,255,255,0.05);
      color: #94a3b8;
    }

    .comparison tr:hover {
      background: rgba(255,255,255,0.03);
    }

    /* Quiz */
    .quiz {
      background: linear-gradient(135deg, rgba(139, 92, 246, 0.1), rgba(236, 72, 153, 0.1));
      border-radius: 22px;
      padding: 32px;
      border: 2px solid rgba(139, 92, 246, 0.3);
    }

    .quiz-q {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 24px;
    }

    .quiz-opts {
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

    .quiz-opt {
      padding: 18px 24px;
      background: var(--card);
      border-radius: 14px;
      cursor: pointer;
      transition: all 0.3s;
      border: 2px solid transparent;
      display: flex;
      align-items: center;
      gap: 16px;
    }

    .quiz-opt:hover {
      border-color: var(--purple);
      transform: translateX(10px);
    }

    .quiz-opt.correct {
      border-color: var(--green);
      background: rgba(16, 185, 129, 0.2);
    }

    .quiz-opt.wrong {
      border-color: var(--red);
      background: rgba(239, 68, 68, 0.2);
    }

    .opt-letter {
      width: 36px;
      height: 36px;
      border-radius: 50%;
      background: rgba(255,255,255,0.1);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
    }

    .quiz-result {
      margin-top: 20px;
      padding: 20px;
      border-radius: 14px;
      text-align: center;
      font-weight: 600;
      display: none;
    }

    .quiz-result.show { 
      display: block; 
      animation: slideUp 0.5s ease-out;
    }

    @keyframes slideUp {
      from { opacity: 0; transform: translateY(20px); }
      to { opacity: 1; transform: translateY(0); }
    }

    /* Playground buttons */
    .playground-btns {
      display: flex;
      gap: 14px;
      justify-content: center;
      flex-wrap: wrap;
      margin: 24px 0;
    }

    .playground-btn {
      background: linear-gradient(135deg, var(--cyan), var(--blue));
      border: none;
      padding: 14px 30px;
      border-radius: 14px;
      color: white;
      font-weight: 700;
      cursor: pointer;
      transition: all 0.3s;
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 1rem;
    }

    .playground-btn:hover {
      transform: translateY(-3px);
      box-shadow: 0 15px 40px rgba(6, 182, 212, 0.5);
    }

    .playground-btn.secondary {
      background: linear-gradient(135deg, var(--purple), var(--pink));
    }

    .playground-btn.danger {
      background: linear-gradient(135deg, var(--red), var(--orange));
    }

    /* FAB */
    .fab {
      position: fixed;
      bottom: 30px;
      right: 30px;
      width: 64px;
      height: 64px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--node), var(--cyan));
      border: none;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.8rem;
      color: white;
      box-shadow: 0 15px 40px rgba(104, 160, 99, 0.5);
      transition: all 0.3s;
      z-index: 100;
      opacity: 0;
      visibility: hidden;
    }

    .fab.show { opacity: 1; visibility: visible; }
    .fab:hover { transform: scale(1.2) rotate(15deg); }

    /* Toast */
    .toast {
      position: fixed;
      bottom: 120px;
      left: 50%;
      transform: translateX(-50%) translateY(120px);
      background: var(--card);
      padding: 18px 35px;
      border-radius: 16px;
      border: 2px solid var(--cyan);
      box-shadow: 0 20px 60px rgba(0,0,0,0.6);
      transition: all 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);
      z-index: 1000;
      opacity: 0;
      max-width: 90%;
    }

    .toast.show {
      transform: translateX(-50%) translateY(0);
      opacity: 1;
    }

    /* Footer */
    footer {
      text-align: center;
      padding: 50px 20px;
      background: var(--card);
      margin-top: 60px;
      border-top: 1px solid rgba(255,255,255,0.08);
    }

    .footer-icons {
      display: flex;
      justify-content: center;
      gap: 20px;
      margin-bottom: 20px;
    }

    .footer-icon {
      width: 54px;
      height: 54px;
      border-radius: 50%;
      background: rgba(255,255,255,0.08);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.6rem;
      cursor: pointer;
      transition: all 0.3s;
    }

    .footer-icon:hover {
      background: var(--node);
      transform: translateY(-8px);
    }

    @media (max-width: 768px) {
      .cmd-buttons { grid-template-columns: 1fr; }
      .playground-btns { flex-direction: column; }
      .playground-btn { width: 100%; justify-content: center; }
      h1 { font-size: 2rem; }
    }
  </style>
</head>
<body>
  <div class="progress" id="progress"></div>
  <div class="bg-animation" id="bgAnim"></div>

  <header>
    <div class="logo-container">
      <div class="node-logo" onclick="celebrate()">⬢</div>
      <div class="repl-demo">
        <span style="color: var(--node);">&gt;</span> 
        <span style="color: var(--yellow);">console.log</span>(<span style="color: var(--cyan);">'Hello Node!'</span>)
      </div>
    </div>
    <h1>Node.js & REPL Mastery</h1>
    <p class="subtitle">Learn to run Node.js and master the interactive REPL environment! 🚀</p>
  </header>

  <main>
    <!-- What is Node.js -->
    <section class="section" id="nodejs">
      <div class="sec-title">
        <div class="sec-icon" style="background: linear-gradient(135deg, var(--node), var(--green));">⬢</div>
        <span>What is Node.js?</span>
      </div>

      <div class="card featured">
        <div class="featured-badge">⭐ ESSENTIAL</div>
        <h3>🚀 JavaScript Runtime Environment</h3>
        <p>Node.js is a powerful JavaScript runtime built on Chrome's V8 engine that lets you run JavaScript outside the browser - on your computer, servers, and more!</p>

        <div class="info cool">
          <span class="info-icon">✨</span>
          <div>
            <strong>Why Node.js is Amazing:</strong>
            <p>Build servers, command-line tools, desktop apps, and more using JavaScript. It's fast, scalable, and has a massive ecosystem of packages!</p>
          </div>
        </div>
      </div>
    </section>

    <!-- What is REPL -->
    <section class="section" id="repl">
      <div class="sec-title">
        <div class="sec-icon" style="background: linear-gradient(135deg, var(--cyan), var(--blue));">💻</div>
        <span>What is REPL?</span>
      </div>

      <div class="card">
        <h3>🔄 Read-Eval-Print Loop</h3>
        <p>REPL is an interactive programming environment where you can type JavaScript code and see results immediately!</p>

        <div class="code-block">
          <div class="code-header">
            <div class="code-dots">
              <div class="dot r"></div>
              <div class="dot y"></div>
              <div class="dot g"></div>
            </div>
            <span class="code-lang">REPL Breakdown</span>
          </div>
          <div class="code-body">
            <span style="color: var(--cyan);">R</span>ead - Reads your input<br>
            <span style="color: var(--purple);">E</span>val - Evaluates the code<br>
            <span style="color: var(--yellow);">P</span>rint - Prints the result<br>
            <span style="color: var(--pink);">L</span>oop - Repeats the process
          </div>
        </div>

        <div class="info tip">
          <span class="info-icon">💡</span>
          <div>
            <strong>Perfect For:</strong>
            <p>Testing code snippets, learning JavaScript, debugging, quick calculations, and experimenting with Node.js features!</p>
          </div>
        </div>
      </div>
    </section>

    <!-- How to Run Node.js -->
    <section class="section" id="run-node">
      <div class="sec-title">
        <div class="sec-icon" style="background: linear-gradient(135deg, var(--purple), var(--pink));">🎯</div>
        <span>How to Run Node.js</span>
      </div>

      <div class="card">
        <h3>📝 Running JavaScript Files</h3>
        <p>Execute JavaScript files using the <code style="color: var(--cyan);">node</code> command!</p>

        <div class="steps">
          <div class="step" onclick="showToast('Step 1: Create your JavaScript file!')">
            <div class="step-num">1</div>
            <div class="step-content">
              <h4>Create a JavaScript File</h4>
              <p>Create a file named <code style="color: var(--cyan);">app.js</code> with your JavaScript code</p>
            </div>
          </div>
          <div class="step" onclick="showToast('Step 2: Open your terminal!')">
            <div class="step-num">2</div>
            <div class="step-content">
              <h4>Open Terminal/Command Prompt</h4>
              <p>Navigate to the folder containing your file</p>
            </div>
          </div>
          <div class="step" onclick="showToast('Step 3: Run with node command!')">
            <div class="step-num">3</div>
            <div class="step-content">
              <h4>Run the File</h4>
              <p>Type: <code style="color: var(--cyan);">node app.js</code></p>
            </div>
          </div>
        </div>

        <div class="code-block">
          <div class="code-header">
            <div class="code-dots">
              <div class="dot r"></div>
              <div class="dot y"></div>
              <div class="dot g"></div>
            </div>
            <span class="code-lang">Example: app.js</span>
            <button class="code-copy" onclick="copyCode(this, 'console.log(\'Hello from Node.js!\');\nconsole.log(\'2 + 2 =\", 2 + 2);')">Copy</button>
          </div>
          <div class="code-body">
            <span class="func">console</span>.<span class="func">log</span>(<span class="str">'Hello from Node.js!'</span>);<br>
            <span class="func">console</span>.<span class="func">log</span>(<span class="str">'2 + 2 ='</span>, <span class="num">2</span> + <span class="num">2</span>);
          </div>
        </div>

        <div class="code-block">
          <div class="code-header">
            <div class="code-dots">
              <div class="dot r"></div>
              <div class="dot y"></div>
              <div class="dot g"></div>
            </div>
            <span class="code-lang">Terminal Command</span>
            <button class="code-copy" onclick="copyCode(this, 'node app.js')">Copy</button>
          </div>
          <div class="code-body">
            $ <span class="func">node</span> app.js<br><br>
            <span class="comment">// Output:</span><br>
            <span style="color: var(--green);">Hello from Node.js!</span><br>
            <span style="color: var(--green);">2 + 2 = 4</span>
          </div>
        </div>
      </div>
    </section>

    <!-- How to Start REPL -->
    <section class="section" id="start-repl">
      <div class="sec-title">
        <div class="sec-icon" style="background: linear-gradient(135deg, var(--orange), var(--yellow));">🔥</div>
        <span>How to Start REPL</span>
      </div>

      <div class="card">
        <h3>🚀 Launching the REPL</h3>
        <p>Starting the REPL is super simple - just type <code style="color: var(--cyan);">node</code> in your terminal!</p>

        <div class="code-block">
          <div class="code-header">
            <div class="code-dots">
              <div class="dot r"></div>
              <div class="dot y"></div>
              <div class="dot g"></div>
            </div>
            <span class="code-lang">Terminal</span>
            <button class="code-copy" onclick="copyCode(this, 'node')">Copy</button>
          </div>
          <div class="code-body">
            $ <span class="func">node</span><br>
            <span style="color: var(--node);">&gt;</span> <span class="cursor"></span>
          </div>
        </div>

        <div class="info important">
          <span class="info-icon">⭐</span>
          <div>
            <strong>That's It!</strong>
            <p>When you see the <code style="color: var(--node);">&gt;</code> prompt, you're in the REPL and ready to code!</p>
          </div>
        </div>
      </div>
    </section>

    <!-- Interactive REPL Playground -->
    <section class="section" id="playground">
      <div class="sec-title">
        <div class="sec-icon" style="background: linear-gradient(135deg, var(--cyan), var(--purple));">🎮</div>
        <span>Interactive REPL Simulator</span>
      </div>

      <div class="repl-container">
        <div class="repl-title">🎯 Try REPL Commands!</div>
        <p style="text-align: center; color: #94a3b8; margin-bottom: 20px;">Click the buttons below to see how REPL works</p>

        <div class="cmd-buttons">
          <div class="cmd-btn" onclick="runREPL('basic')">
            <div class="cmd-btn-icon">🔢</div>
            <div class="cmd-btn-title">Basic Math</div>
            <div class="cmd-btn-desc">Simple calculations</div>
          </div>
          <div class="cmd-btn" onclick="runREPL('variables')">
            <div class="cmd-btn-icon">📦</div>
            <div class="cmd-btn-title">Variables</div>
            <div class="cmd-btn-desc">Create & use variables</div>
          </div>
          <div class="cmd-btn" onclick="runREPL('functions')">
            <div class="cmd-btn-icon">⚡</div>
            <div class="cmd-btn-title">Functions</div>
            <div class="cmd-btn-desc">Define functions</div>
          </div>
          <div class="cmd-btn" onclick="runREPL('arrays')">
            <div class="cmd-btn-icon">📊</div>
            <div class="cmd-btn-title">Arrays</div>
            <div class="cmd-btn-desc">Work with arrays</div>
          </div>
        </div>

        <div class="terminal">
          <div class="term-header">
            <div class="dot r"></div>
            <div class="dot y"></div>
            <div class="dot g"></div>
            <span class="term-title">Node.js REPL</span>
          </div>
          <div class="term-body" id="replOutput">
            <div class="term-line">
              <span style="color: #64748b;">Welcome to Node.js REPL!</span>
            </div>
            <div class="term-line">
              <span style="color: #64748b;">Click a button above to try different commands</span>
            </div>
            <div class="term-line"><span class="prompt">&gt;</span> <span class="cursor"></span></div>
          </div>
        </div>

        <div class="playground-btns">
          <button class="playground-btn secondary" onclick="clearREPL()">
            🗑️ Clear
          </button>
          <button class="playground-btn" onclick="runREPL('demo')">
            ▶️ Run Full Demo
          </button>
        </div>
      </div>
    </section>

    <!-- REPL Commands -->
    <section class="section" id="commands">
      <div class="sec-title">
        <div class="sec-icon" style="background: linear-gradient(135deg, var(--green), var(--cyan));">⌨️</div>
        <span>Essential REPL Commands</span>
      </div>

      <div class="card">
        <h3>🎯 Special Commands</h3>
        <p>REPL has special commands that start with a dot (.):</p>

        <div class="comparison">
          <table>
            <thead>
              <tr>
                <th>Command</th>
                <th>Description</th>
                <th>Example</th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td><code>.help</code></td>
                <td>Show all REPL commands</td>
                <td>Lists available commands</td>
              </tr>
              <tr>
                <td><code>.exit</code></td>
                <td>Exit the REPL</td>
                <td>Closes REPL session</td>
              </tr>
              <tr>
                <td><code>.clear</code></td>
                <td>Clear the context</td>
                <td>Resets all variables</td>
              </tr>
              <tr>
                <td><code>.save</code></td>
                <td>Save session to file</td>
                <td>.save session.js</td>
              </tr>
              <tr>
                <td><code>.load</code></td>
                <td>Load file into REPL</td>
                <td>.load mycode.js</td>
              </tr>
              <tr>
                <td><code>.editor</code></td>
                <td>Enter editor mode</td>
                <td>Multi-line editing</td>
              </tr>
            </tbody>
          </table>
        </div>

        <div class="info tip">
          <span class="info-icon">💡</span>
          <div>
            <strong>Pro Tip:</strong>
            <p>Press <kbd style="background: var(--card); padding: 2px 8px; border-radius: 4px;">Ctrl + C</kbd> twice to exit REPL, or <kbd style="background: var(--card); padding: 2px 8px; border-radius: 4px;">Ctrl + D</kbd> once!</p>
          </div>
        </div>
      </div>
    </section>

    <!-- REPL Features -->
    <section class="section" id="features">
      <div class="sec-title">
        <div class="sec-icon" style="background: linear-gradient(135deg, var(--yellow), var(--orange));">✨</div>
        <span>Cool REPL Features</span>
      </div>

      <div class="card">
        <h3>🎨 Amazing Features</h3>

        <div class="info cool">
          <span class="info-icon">🔍</span>
          <div>
            <strong>Tab Completion:</strong>
            <p>Press <kbd style="background: var(--card); padding: 2px 8px; border-radius: 4px;">Tab</kbd> to auto-complete variable names, methods, and properties!</p>
          </div>
        </div>

        <div class="info cool">
          <span class="info-icon">📜</span>
          <div>
            <strong>Command History:</strong>
            <p>Use <kbd style="background: var(--card); padding: 2px 8px; border-radius: 4px;">↑</kbd> and <kbd style="background: var(--card); padding: 2px 8px; border-radius: 4px;">↓</kbd> arrow keys to navigate through previous commands!</p>
          </div>
        </div>

        <div class="info cool">
          <span class="info-icon">🎯</span>
          <div>
            <strong>Underscore Variable:</strong>
            <p>Use <code style="color: var(--cyan);">_</code> to access the result of the last expression!</p>
          </div>
        </div>

        <div class="code-block">
          <div class="code-header">
            <div class="code-dots">
              <div class="dot r"></div>
              <div class="dot y"></div>
              <div class="dot g"></div>
            </div>
            <span class="code-lang">Underscore Example</span>
            <button class="code-copy" onclick="copyCode(this, '> 5 + 5\n10\n> _ * 2\n20')">Copy</button>
          </div>
          <div class="code-body">
            <span class="prompt">&gt;</span> <span class="num">5</span> + <span class="num">5</span><br>
            <span style="color: var(--green);">10</span><br>
            <span class="prompt">&gt;</span> <span class="var">_</span> * <span class="num">2</span><br>
            <span style="color: var(--green);">20</span>
          </div>
        </div>
      </div>
    </section>

    <!-- Node vs REPL -->
    <section class="section" id="comparison">
      <div class="sec-title">
        <div class="sec-icon" style="background: linear-gradient(135deg, var(--pink), var(--purple));">⚖️</div>
        <span>Node.js vs REPL</span>
      </div>

      <div class="card">
        <h3>🔄 When to Use Each</h3>

        <div class="comparison">
          <table>
            <thead>
              <tr>
                <th>Feature</th>
                <th>node filename.js</th>
                <th>REPL (node)</th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td>Purpose</td>
                <td>Run complete programs</td>
                <td>Interactive testing</td>
              </tr>
              <tr>
                <td>Best For</td>
                <td>Applications, scripts</td>
                <td>Learning, debugging</td>
              </tr>
              <tr>
                <td>Code Persistence</td>
                <td>Saved in files</td>
                <td>Lost when closed</td>
              </tr>
              <tr>
                <td>Execution</td>
                <td>Runs entire file</td>
                <td>Line by line</td>
              </tr>
              <tr>
                <td>Output</td>
                <td>Only console.log()</td>
                <td>Automatic display</td>
              </tr>
            </tbody>
          </table>
        </div>

        <div class="info important">
          <span class="info-icon">🎯</span>
          <div>
            <strong>Use Both!</strong>
            <p>Use REPL for quick tests and learning, then write your real code in files and run with <code style="color: var(--cyan);">node filename.js</code>!</p>
          </div>
        </div>
      </div>
    </section>

    <!-- Quiz -->
    <section class="section" id="quiz">
      <div class="sec-title">
        <div class="sec-icon" style="background: linear-gradient(135deg, var(--orange), var(--red));">🧠</div>
        <span>Test Your Knowledge!</span>
      </div>

      <div class="quiz">
        <div class="quiz-q">What command starts the Node.js REPL?</div>
        <div class="quiz-opts">
          <div class="quiz-opt" onclick="checkQuiz(this, false)">
            <span class="opt-letter">A</span>
            <span>node repl</span>
          </div>
          <div class="quiz-opt" onclick="checkQuiz(this, true)">
            <span class="opt-letter">B</span>
            <span>node</span>
          </div>
          <div class="quiz-opt" onclick="checkQuiz(this, false)">
            <span class="opt-letter">C</span>
            <span>node start</span>
          </div>
          <div class="quiz-opt" onclick="checkQuiz(this, false)">
            <span class="opt-letter">D</span>
            <span>repl</span>
          </div>
        </div>
        <div class="quiz-result" id="quizResult"></div>
      </div>
    </section>
  </main>

  <button class="fab" id="fab" onclick="scrollTop()">⬆️</button>
  <div class="toast" id="toast"></div>

  <footer>
    <div class="footer-icons">
      <div class="footer-icon">⬢</div>
      <div class="footer-icon">💻</div>
      <div class="footer-icon">🚀</div>
      <div class="footer-icon">✨</div>
    </div>
    <p style="color: #64748b;">Master Node.js and REPL! 🎉</p>
    <p style="color: #475569; font-size: 0.85rem; margin-top: 8px;">Happy coding with JavaScript everywhere!</p>
  </footer>

  <script>
    // Background animation
    const bgAnim = document.getElementById('bgAnim');
    
    // Create floating symbols
    const symbols = ['⬢', '>', '{', '}', '(', ')', '=>', '...'];
    for (let i = 0; i < 10; i++) {
      const symbol = document.createElement('div');
      symbol.className = 'float-symbol';
      symbol.textContent = symbols[Math.floor(Math.random() * symbols.length)];
      symbol.style.left = Math.random() * 100 + '%';
      symbol.style.top = Math.random() * 100 + '%';
      symbol.style.animationDelay = Math.random() * 5 + 's';
      symbol.style.animationDuration = (Math.random() * 15 + 15) + 's';
      bgAnim.appendChild(symbol);
    }

    // Create orbs
    const colors = ['var(--node)', 'var(--cyan)', 'var(--purple)'];
    for (let i = 0; i < 3; i++) {
      const orb = document.createElement('div');
      orb.className = 'orb';
      orb.style.width = (Math.random() * 400 + 250) + 'px';
      orb.style.height = orb.style.width;
      orb.style.left = Math.random() * 100 + '%';
      orb.style.top = Math.random() * 100 + '%';
      orb.style.background = colors[i];
      orb.style.animationDelay = i * 5 + 's';
      bgAnim.appendChild(orb);
    }

    // Scroll animations
    const sections = document.querySelectorAll('.section');
    const obs = new IntersectionObserver((entries) => {
      entries.forEach(e => {
        if (e.isIntersecting) e.target.classList.add('vis');
      });
    }, { threshold: 0.1 });
    sections.forEach(s => obs.observe(s));

    // Progress bar
    window.addEventListener('scroll', () => {
      const scrolled = (window.scrollY / (document.body.scrollHeight - window.innerHeight)) * 100;
      document.getElementById('progress').style.width = scrolled + '%';
      document.getElementById('fab').classList.toggle('show', window.scrollY > 300);
    });

    // Toast
    function showToast(msg) {
      const toast = document.getElementById('toast');
      toast.textContent = '✨ ' + msg;
      toast.classList.add('show');
      setTimeout(() => toast.classList.remove('show'), 2500);
    }

    // Copy code
    function copyCode(btn, code) {
      navigator.clipboard.writeText(code);
      btn.textContent = 'Copied!';
      btn.classList.add('copied');
      showToast('Code copied to clipboard!');
      setTimeout(() => {
        btn.textContent = 'Copy';
        btn.classList.remove('copied');
      }, 2000);
    }

    // REPL Simulator
    const replExamples = {
      basic: [
        { input: '2 + 2', output: '4', delay: 500 },
        { input: '10 * 5', output: '50', delay: 600 },
        { input: 'Math.sqrt(16)', output: '4', delay: 700 }
      ],
      variables: [
        { input: 'let name = "Alice"', output: 'undefined', delay: 500 },
        { input: 'name', output: "'Alice'", delay: 600 },
        { input: 'let age = 25', output: 'undefined', delay: 700 },
        { input: 'age + 5', output: '30', delay: 800 }
      ],
      functions: [
        { input: 'function greet(name) { return "Hello " + name; }', output: 'undefined', delay: 500 },
        { input: 'greet("World")', output: "'Hello World'", delay: 700 },
        { input: 'const add = (a, b) => a + b', output: 'undefined', delay: 800 },
        { input: 'add(5, 3)', output: '8', delay: 900 }
      ],
      arrays: [
        { input: 'let fruits = ["apple", "banana", "cherry"]', output: 'undefined', delay: 500 },
        { input: 'fruits', output: "[ 'apple', 'banana', 'cherry' ]", delay: 700 },
        { input: 'fruits.length', output: '3', delay: 800 },
        { input: 'fruits[1]', output: "'banana'", delay: 900 }
      ],
      demo: [
        { input: 'console.log("Welcome to REPL!")', output: 'Welcome to REPL!\nundefined', delay: 500 },
        { input: '5 + 5', output: '10', delay: 700 },
        { input: '_ * 2', output: '20', delay: 900 },
        { input: 'let x = 100', output: 'undefined', delay: 1100 },
        { input: 'x / 4', output: '25', delay: 1300 },
        { input: '[1, 2, 3].map(n => n * 2)', output: '[ 2, 4, 6 ]', delay: 1500 }
      ]
    };

    function runREPL(type) {
      const output = document.getElementById('replOutput');
      output.innerHTML = '';
      
      const examples = replExamples[type];
      let totalDelay = 0;

      examples.forEach((ex, i) => {
        totalDelay += ex.delay;
        
        setTimeout(() => {
          // Add input line
          const inputLine = document.createElement('div');
          inputLine.className = 'term-line';
          inputLine.innerHTML = `<span class="prompt">&gt;</span> <span style="color: var(--cyan);">${ex.input}</span>`;
          output.appendChild(inputLine);
          
          // Add output line
          setTimeout(() => {
            const outputLine = document.createElement('div');
            outputLine.className = 'term-line';
            outputLine.innerHTML = `<span style="color: var(--green);">${ex.output}</span>`;
            output.appendChild(outputLine);
            
            // Add cursor at the end
            if (i === examples.length - 1) {
              const cursorLine = document.createElement('div');
              cursorLine.className = 'term-line';
              cursorLine.innerHTML = '<span class="prompt">&gt;</span> <span class="cursor"></span>';
              output.appendChild(cursorLine);
            }
            
            output.scrollTop = output.scrollHeight;
          }, 200);
        }, totalDelay);
      });

      showToast(`Running ${type} example!`);
    }

    function clearREPL() {
      const output = document.getElementById('replOutput');
      output.innerHTML = '<div class="term-line"><span class="prompt">&gt;</span> <span class="cursor"></span></div>';
      showToast('REPL cleared!');
    }

    // Quiz
    function checkQuiz(el, correct) {
      const opts = document.querySelectorAll('.quiz-opt');
      opts.forEach(o => {
        o.style.pointerEvents = 'none';
        o.classList.remove('correct', 'wrong');
      });
      
      el.classList.add(correct ? 'correct' : 'wrong');
      if (!correct) opts[1].classList.add('correct');
      
      const result = document.getElementById('quizResult');
      result.className = 'quiz-result show';
      result.style.background = correct ? 'rgba(16,185,129,0.2)' : 'rgba(239,68,68,0.2)';
      result.innerHTML = correct 
        ? '🎉 Correct! Just type <code style="color: var(--cyan);">node</code> to start the REPL!'
        : '❌ Not quite! The command is simply <code style="color: var(--cyan);">node</code> with no arguments.';
      
      if (correct) celebrate();
    }

    // Celebrate
    function celebrate() {
      const colors = ['var(--node)', 'var(--cyan)', 'var(--purple)', 'var(--yellow)', 'var(--pink)'];
      for (let i = 0; i < 40; i++) {
        const confetti = document.createElement('div');
        confetti.style.position = 'fixed';
        confetti.style.width = '12px';
        confetti.style.height = '12px';
        confetti.style.background = colors[Math.floor(Math.random() * colors.length)];
        confetti.style.left = Math.random() * 100 + '%';
        confetti.style.top = '-30px';
        confetti.style.borderRadius = Math.random() > 0.5 ? '50%' : '0';
        confetti.style.zIndex = '9999';
        confetti.style.pointerEvents = 'none';
        document.body.appendChild(confetti);
        
        const fall = confetti.animate([
          { transform: 'translateY(0) rotate(0deg)', opacity: 1 },
          { transform: `translateY(100vh) rotate(${Math.random() * 720}deg)`, opacity: 0 }
        ], {
          duration: Math.random() * 2500 + 2000,
          easing: 'cubic-bezier(0.25, 0.46, 0.45, 0.94)'
        });
        
        fall.onfinish = () => confetti.remove();
      }
    }

    // Scroll to top
    function scrollTop() {
      window.scrollTo({ top: 0, behavior: 'smooth' });
    }

    // Initial visibility
    setTimeout(() => sections[0].classList.add('vis'), 300);
  </script>
</body>
</html>
Live Preview