Animated Confetti Background in CSS

<!-- Confetti Background -->
<div class="confetti-container" id="confettiContainer"></div>

<!-- Main Content -->
<div class="content">
  <div class="hero">
    <h1>🎉 Celebrate!</h1>
    <p>Beautiful animated confetti raining down</p>
    <button class="celebration-btn" onclick="burstConfetti()">Add More Confetti</button>
  </div>

  <div class="features">
    <div class="feature-card">
      <div class="feature-icon">🎨</div>
      <div class="feature-title">Colorful Design</div>
      <div class="feature-desc">
        Multiple vibrant colors including red, orange, yellow, green, cyan, blue, pink, and more creating a festive atmosphere.
      </div>
    </div>

    <div class="feature-card">
      <div class="feature-icon">✨</div>
      <div class="feature-title">Pure CSS</div>
      <div class="feature-desc">
        Smooth animations powered entirely by CSS with optional JavaScript for interactive confetti bursts.
      </div>
    </div>

    <div class="feature-card">
      <div class="feature-icon">🎊</div>
      <div class="feature-title">Multiple Shapes</div>
      <div class="feature-desc">
        Includes squares, circles, triangles, rectangles, and stars for variety and realistic confetti effects.
      </div>
    </div>
  </div>
</div>

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

    body {
      font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
      background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
      min-height: 100vh;
      overflow-x: hidden;
      position: relative;
    }

    /* Confetti Container */
    .confetti-container {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      overflow: hidden;
      pointer-events: none;
      z-index: 1;
    }

    /* Confetti Base */
    .confetti {
      position: absolute;
      width: 10px;
      height: 10px;
      opacity: 0.8;
      animation: fall linear infinite;
    }

    /* Confetti Shapes */
    .confetti.square {
      border-radius: 2px;
    }

    .confetti.circle {
      border-radius: 50%;
    }

    .confetti.triangle {
      width: 0;
      height: 0;
      border-left: 5px solid transparent;
      border-right: 5px solid transparent;
      border-bottom: 10px solid;
    }

    .confetti.rectangle {
      width: 15px;
      height: 8px;
      border-radius: 2px;
    }

    .confetti.star {
      clip-path: polygon(50% 0%, 61% 35%, 98% 35%, 68% 57%, 79% 91%, 50% 70%, 21% 91%, 32% 57%, 2% 35%, 39% 35%);
    }

    /* Colors - Red */
    .confetti-red { background: #ff6b6b; }
    .confetti.triangle.confetti-red { border-bottom-color: #ff6b6b; }

    /* Colors - Orange */
    .confetti-orange { background: #ffa500; }
    .confetti.triangle.confetti-orange { border-bottom-color: #ffa500; }

    /* Colors - Yellow */
    .confetti-yellow { background: #ffd93d; }
    .confetti.triangle.confetti-yellow { border-bottom-color: #ffd93d; }

    /* Colors - Green */
    .confetti-green { background: #6bcf7f; }
    .confetti.triangle.confetti-green { border-bottom-color: #6bcf7f; }

    /* Colors - Cyan */
    .confetti-cyan { background: #4ecdc4; }
    .confetti.triangle.confetti-cyan { border-bottom-color: #4ecdc4; }

    /* Colors - Blue */
    .confetti-blue { background: #1e90ff; }
    .confetti.triangle.confetti-blue { border-bottom-color: #1e90ff; }

    /* Colors - Pink */
    .confetti-pink { background: #ff69b4; }
    .confetti.triangle.confetti-pink { border-bottom-color: #ff69b4; }

    /* Colors - Magenta */
    .confetti-magenta { background: #ff1493; }
    .confetti.triangle.confetti-magenta { border-bottom-color: #ff1493; }

    /* Colors - Lime */
    .confetti-lime { background: #32cd32; }
    .confetti.triangle.confetti-lime { border-bottom-color: #32cd32; }

    /* Colors - Gold */
    .confetti-gold { background: #ffd700; }
    .confetti.triangle.confetti-gold { border-bottom-color: #ffd700; }

    /* Fall Animation */
    @keyframes fall {
      0% {
        transform: translateY(-100px) rotate(0deg);
        opacity: 1;
      }
      100% {
        transform: translateY(100vh) rotate(720deg);
        opacity: 0.3;
      }
    }

    /* Swing Animation */
    @keyframes swing {
      0%, 100% {
        transform: translateX(0) rotate(0deg);
      }
      25% {
        transform: translateX(50px) rotate(90deg);
      }
      50% {
        transform: translateX(0) rotate(180deg);
      }
      75% {
        transform: translateX(-50px) rotate(270deg);
      }
    }

    /* Spin Animation */
    @keyframes spin {
      0% {
        transform: rotate(0deg) scale(1);
      }
      50% {
        transform: rotate(180deg) scale(1.2);
      }
      100% {
        transform: rotate(360deg) scale(1);
      }
    }

    /* Content Layer */
    .content {
      position: relative;
      z-index: 10;
      min-height: 100vh;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 40px 20px;
    }

    .hero {
      text-align: center;
      color: white;
      animation: fadeInUp 1s ease;
    }

    .hero h1 {
      font-size: 4.5rem;
      font-weight: 700;
      margin-bottom: 20px;
      background: linear-gradient(45deg, #ff6b6b, #ffa500, #ffd93d, #6bcf7f, #4ecdc4, #1e90ff, #ff69b4);
      background-size: 200% 200%;
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      animation: gradientShift 3s ease infinite;
    }

    @keyframes gradientShift {
      0% { background-position: 0% 50%; }
      50% { background-position: 100% 50%; }
      100% { background-position: 0% 50%; }
    }

    .hero p {
      font-size: 1.5rem;
      margin-bottom: 40px;
      color: rgba(255, 255, 255, 0.9);
    }

    @keyframes fadeInUp {
      from {
        opacity: 0;
        transform: translateY(50px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    .celebration-btn {
      background: linear-gradient(135deg, #ff6b6b 0%, #ffa500 100%);
      color: white;
      padding: 18px 45px;
      border: none;
      border-radius: 50px;
      font-size: 1.3rem;
      font-weight: 700;
      cursor: pointer;
      transition: all 0.3s ease;
      box-shadow: 0 10px 30px rgba(255, 107, 107, 0.4);
      text-transform: uppercase;
      letter-spacing: 2px;
      animation: fadeInUp 1s ease 0.3s backwards;
    }

    .celebration-btn:hover {
      transform: translateY(-5px) scale(1.05);
      box-shadow: 0 15px 40px rgba(255, 107, 107, 0.6);
    }

    .celebration-btn:active {
      transform: translateY(-2px) scale(1.02);
    }

    /* Feature Cards */
    .features {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 30px;
      max-width: 1200px;
      margin-top: 80px;
      width: 100%;
    }

    .feature-card {
      background: rgba(255, 255, 255, 0.1);
      backdrop-filter: blur(10px);
      border-radius: 20px;
      padding: 40px;
      border: 2px solid rgba(255, 255, 255, 0.2);
      transition: all 0.4s ease;
      animation: fadeInUp 1s ease backwards;
    }

    .feature-card:nth-child(1) { animation-delay: 0.5s; }
    .feature-card:nth-child(2) { animation-delay: 0.7s; }
    .feature-card:nth-child(3) { animation-delay: 0.9s; }

    .feature-card:hover {
      transform: translateY(-15px);
      background: rgba(255, 255, 255, 0.15);
      border-color: rgba(255, 255, 255, 0.4);
      box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
    }

    .feature-icon {
      font-size: 4rem;
      margin-bottom: 20px;
      animation: bounce 2s ease-in-out infinite;
    }

    .feature-card:nth-child(2) .feature-icon {
      animation-delay: 0.3s;
    }

    .feature-card:nth-child(3) .feature-icon {
      animation-delay: 0.6s;
    }

    @keyframes bounce {
      0%, 100% {
        transform: translateY(0);
      }
      50% {
        transform: translateY(-15px);
      }
    }

    .feature-title {
      font-size: 1.8rem;
      color: white;
      font-weight: 700;
      margin-bottom: 15px;
    }

    .feature-desc {
      color: rgba(255, 255, 255, 0.8);
      line-height: 1.8;
      font-size: 1.1rem;
    }

    @media (max-width: 768px) {
      .hero h1 {
        font-size: 2.5rem;
      }

      .hero p {
        font-size: 1.2rem;
      }

      .celebration-btn {
        padding: 15px 35px;
        font-size: 1rem;
      }

      .features {
        grid-template-columns: 1fr;
        margin-top: 50px;
      }
    }

  const container = document.getElementById('confettiContainer');
    const colors = ['red', 'orange', 'yellow', 'green', 'cyan', 'blue', 'pink', 'magenta', 'lime', 'gold'];
    const shapes = ['square', 'circle', 'triangle', 'rectangle', 'star'];

    function createConfetti() {
      const confetti = document.createElement('div');
      confetti.classList.add('confetti');
      
      // Random shape
      const shape = shapes[Math.floor(Math.random() * shapes.length)];
      confetti.classList.add(shape);
      
      // Random color
      const color = colors[Math.floor(Math.random() * colors.length)];
      confetti.classList.add('confetti-' + color);
      
      // Random position
      confetti.style.left = Math.random() * 100 + '%';
      
      // Random size
      const size = Math.random() * 10 + 8;
      if (shape !== 'triangle') {
        confetti.style.width = size + 'px';
        confetti.style.height = size + 'px';
      }
      
      if (shape === 'rectangle') {
        confetti.style.width = (size * 1.5) + 'px';
      }
      
      // Random animation duration
      const duration = Math.random() * 3 + 3;
      confetti.style.animationDuration = duration + 's';
      
      // Random delay
      confetti.style.animationDelay = Math.random() * 2 + 's';
      
      container.appendChild(confetti);
      
      // Remove after animation
      setTimeout(() => {
        confetti.remove();
      }, (duration + 2) * 1000);
    }

    // Create initial confetti
    function initConfetti() {
      for (let i = 0; i < 80; i++) {
        setTimeout(createConfetti, i * 100);
      }
    }

    // Continuous confetti
    function continuousConfetti() {
      createConfetti();
      setTimeout(continuousConfetti, 300);
    }

    // Burst effect
    function burstConfetti() {
      for (let i = 0; i < 50; i++) {
        setTimeout(createConfetti, i * 30);
      }
    }

    // Initialize
    initConfetti();
    setTimeout(continuousConfetti, 3000);