diff --git a/css/game.css b/css/game.css
index d6b4681..2febed7 100644
--- a/css/game.css
+++ b/css/game.css
@@ -556,6 +556,32 @@ h2, h3 {
     }
 }
 
+/* Particle Effects */
+.particle {
+    will-change: transform, opacity;
+}
+
+/* Ambient Stars Background */
+.ambient-star {
+    position: absolute;
+    background: radial-gradient(circle, #ffffff 0%, transparent 70%);
+    border-radius: 50%;
+    animation: twinkle ease-in-out infinite;
+    pointer-events: none;
+    z-index: 1;
+}
+
+@keyframes twinkle {
+    0%, 100% {
+        opacity: 0.2;
+        transform: scale(1);
+    }
+    50% {
+        opacity: 0.8;
+        transform: scale(1.3);
+    }
+}
+
 /* Scrollbar Styling */
 ::-webkit-scrollbar {
     width: 8px;
diff --git a/dev-journal.md b/dev-journal.md
index c8d58de..8128e87 100644
--- a/dev-journal.md
+++ b/dev-journal.md
@@ -29,3 +29,29 @@ The stats panel tracks and displays:
 - Visual effects (particle effects on click)
 - Mobile touch optimizations
 - Prestige/reset system
+
+---
+
+### Session 1 - 2026-08-19 (14:35 UTC)
+**Status:** ✅ Particle Effects System Added
+
+#### What was done:
+- Created a complete particle effects system for visual feedback
+- Added click sparkle particles when harvesting stardust
+- Added building purchase burst effects on the building card
+- Added achievement unlock celebration effects
+- Added ambient twinkling stars to the background
+- Integrated particles into game.js, achievements.js, and main.js
+
+#### Files modified:
+- `js/particles.js` - New file with Particle system (click, building, achievement effects + ambient stars)
+- `js/game.js` - Added particle calls on harvest and buyBuilding
+- `js/achievements.js` - Added particle effect on achievement unlock
+- `js/main.js` - Added ambient star creation on init
+- `css/game.css` - Added particle styles and twinkle animation
+- `index.html` - Added particles.js script tag
+
+#### Next goals:
+- Mobile touch optimizations (tap feedback, responsive layout)
+- Prestige/reset system with bonuses
+- Sound effects for clicks and purchases
diff --git a/index.html b/index.html
index ebd52ec..6f6d7aa 100644
--- a/index.html
+++ b/index.html
@@ -102,6 +102,7 @@
     <script src="js/achievements.js"></script>
     <script src="js/ui.js"></script>
     <script src="js/stats.js"></script>
+    <script src="js/particles.js"></script>
     <script src="js/main.js"></script>
 </body>
 </html>
diff --git a/js/achievements.js b/js/achievements.js
index dcc5f42..8fad98d 100644
--- a/js/achievements.js
+++ b/js/achievements.js
@@ -164,6 +164,14 @@ const Achievements = {
             if (achievement.condition(Game.state)) {
                 Game.state.achievements.push(id);
                 UI.showNotification(`Achievement: ${achievement.name}!`, 'achievement');
+                
+                // Particle effect for achievement unlock
+                const countEl = document.querySelector('#achievements-tab h3');
+                if (countEl) {
+                    const rect = countEl.getBoundingClientRect();
+                    Particles.createAchievementEffect(rect.left + rect.width / 2, rect.top + rect.height / 2);
+                }
+                
                 console.log(`🏆 Achievement unlocked: ${achievement.name}`);
             }
         }
diff --git a/js/game.js b/js/game.js
index c19e11e..d9fc4f5 100644
--- a/js/game.js
+++ b/js/game.js
@@ -101,6 +101,7 @@ const Game = {
         
         // Visual feedback
         UI.showFloatingText(event.clientX, event.clientY, `+${this.formatNumber(amount)}`);
+        Particles.createClickParticles(event.clientX, event.clientY, 8);
         UI.update();
     },
 
@@ -180,6 +181,14 @@ const Game = {
             this.state.buildings[buildingId] = (this.state.buildings[buildingId] || 0) + 1;
             
             UI.showNotification(`Bought ${BUILDINGS[buildingId].name}!`, 'success');
+            
+            // Particle effect on building purchase
+            const card = document.getElementById(`building-${buildingId}`);
+            if (card) {
+                const rect = card.getBoundingClientRect();
+                Particles.createBuildingEffect(rect.left + rect.width / 2, rect.top + rect.height / 2);
+            }
+            
             UI.update();
             return true;
         }
diff --git a/js/main.js b/js/main.js
index b98535e..0af88cd 100644
--- a/js/main.js
+++ b/js/main.js
@@ -5,6 +5,9 @@
 document.addEventListener('DOMContentLoaded', () => {
     Game.init();
     
+    // Create ambient background stars
+    Particles.createAmbientStars(15);
+    
     // Show last save time
     const lastSave = SaveSystem.getLastSaveTime();
     if (lastSave) {
diff --git a/js/particles.js b/js/particles.js
new file mode 100644
index 0000000..a46a68a
--- /dev/null
+++ b/js/particles.js
@@ -0,0 +1,184 @@
+/**
+ * Cosmic Garden - Particle System
+ * Creates visual particle effects for clicks and achievements
+ */
+
+const Particles = {
+    /**
+     * Create sparkle particles on click
+     */
+    createClickParticles(x, y, count = 8) {
+        const colors = ['#ffd700', '#9b59b6', '#3498db', '#2ecc71', '#ffffff'];
+        
+        for (let i = 0; i < count; i++) {
+            const particle = document.createElement('div');
+            particle.className = 'particle';
+            
+            // Random properties
+            const angle = (Math.PI * 2 * i) / count + (Math.random() - 0.5);
+            const velocity = 50 + Math.random() * 50;
+            const size = 6 + Math.random() * 8;
+            const color = colors[Math.floor(Math.random() * colors.length)];
+            
+            particle.style.cssText = `
+                left: ${x}px;
+                top: ${y}px;
+                width: ${size}px;
+                height: ${size}px;
+                background: ${color};
+                border-radius: 50%;
+                pointer-events: none;
+                position: fixed;
+                z-index: 998;
+            `;
+            
+            document.body.appendChild(particle);
+            
+            // Animate
+            const animation = particle.animate([
+                { 
+                    transform: 'translate(-50%, -50%) scale(1)', 
+                    opacity: 1 
+                },
+                { 
+                    transform: `translate(calc(-50% + ${Math.cos(angle) * velocity}px), calc(-50% + ${Math.sin(angle) * velocity}px)) scale(0)`, 
+                    opacity: 0 
+                }
+            ], {
+                duration: 600 + Math.random() * 200,
+                easing: 'cubic-bezier(0, 0.9, 0.57, 1)'
+            });
+            
+            animation.onfinish = () => particle.remove();
+        }
+    },
+
+    /**
+     * Create achievement unlock effect
+     */
+    createAchievementEffect(x, y) {
+        const colors = ['#ffd700', '#ff6b6b', '#4ecdc4', '#45b7d1', '#96ceb4'];
+        
+        // Burst of particles
+        for (let i = 0; i < 20; i++) {
+            const particle = document.createElement('div');
+            particle.className = 'particle achievement-particle';
+            
+            const angle = (Math.PI * 2 * i) / 20;
+            const velocity = 80 + Math.random() * 60;
+            const size = 8 + Math.random() * 12;
+            const color = colors[Math.floor(Math.random() * colors.length)];
+            
+            particle.style.cssText = `
+                left: ${x}px;
+                top: ${y}px;
+                width: ${size}px;
+                height: ${size}px;
+                background: ${color};
+                border-radius: 50%;
+                pointer-events: none;
+                position: fixed;
+                z-index: 998;
+                box-shadow: 0 0 10px ${color};
+            `;
+            
+            document.body.appendChild(particle);
+            
+            const animation = particle.animate([
+                { 
+                    transform: 'translate(-50%, -50%) scale(1)', 
+                    opacity: 1 
+                },
+                { 
+                    transform: `translate(calc(-50% + ${Math.cos(angle) * velocity}px), calc(-50% + ${Math.sin(angle) * velocity}px)) scale(0.5)`, 
+                    opacity: 0.8 
+                },
+                { 
+                    transform: `translate(calc(-50% + ${Math.cos(angle) * velocity * 1.5}px), calc(-50% + ${Math.sin(angle) * velocity * 1.5}px)) scale(0)`, 
+                    opacity: 0 
+                }
+            ], {
+                duration: 1000,
+                easing: 'cubic-bezier(0.25, 0.46, 0.45, 0.94)'
+            });
+            
+            animation.onfinish = () => particle.remove();
+        }
+    },
+
+    /**
+     * Create building purchase effect
+     */
+    createBuildingEffect(x, y) {
+        const colors = ['#2ecc71', '#27ae60', '#1abc9c'];
+        
+        for (let i = 0; i < 12; i++) {
+            const particle = document.createElement('div');
+            particle.className = 'particle building-particle';
+            
+            const angle = (Math.PI * 2 * i) / 12;
+            const velocity = 60 + Math.random() * 40;
+            const size = 5 + Math.random() * 6;
+            const color = colors[Math.floor(Math.random() * colors.length)];
+            
+            particle.style.cssText = `
+                left: ${x}px;
+                top: ${y}px;
+                width: ${size}px;
+                height: ${size}px;
+                background: ${color};
+                border-radius: 2px;
+                pointer-events: none;
+                position: fixed;
+                z-index: 998;
+            `;
+            
+            document.body.appendChild(particle);
+            
+            const animation = particle.animate([
+                { 
+                    transform: 'translate(-50%, -50%) rotate(0deg) scale(1)', 
+                    opacity: 1 
+                },
+                { 
+                    transform: `translate(calc(-50% + ${Math.cos(angle) * velocity}px), calc(-50% + ${Math.sin(angle) * velocity}px)) rotate(${360 + Math.random() * 180}deg) scale(0)`, 
+                    opacity: 0 
+                }
+            ], {
+                duration: 700,
+                easing: 'ease-out'
+            });
+            
+            animation.onfinish = () => particle.remove();
+        }
+    },
+
+    /**
+     * Create ambient floating stars in the background
+     */
+    createAmbientStars(count = 15) {
+        for (let i = 0; i < count; i++) {
+            const star = document.createElement('div');
+            star.className = 'ambient-star';
+            
+            const size = 2 + Math.random() * 3;
+            const left = Math.random() * 100;
+            const delay = Math.random() * 5;
+            const duration = 3 + Math.random() * 2;
+            
+            star.style.cssText = `
+                width: ${size}px;
+                height: ${size}px;
+                left: ${left}%;
+                top: ${Math.random() * 100}%;
+                animation-delay: ${delay}s;
+                animation-duration: ${duration}s;
+            `;
+            
+            document.getElementById('game-container').appendChild(star);
+        }
+    }
+};
+
+// Make globally accessible
+window.Particles = Particles;