diff --git a/beango/css/beango.css b/beango/css/beango.css
index c429952..bd09dd7 100644
--- a/beango/css/beango.css
+++ b/beango/css/beango.css
@@ -233,3 +233,35 @@ details[open] > .config-summary::before {
 .config-content {
     padding-left: 1.5rem; /* Indent content */
 }
+
+/* --- Animation for winning cells --- */
+@keyframes pulse {
+    0% {
+        transform: scale(1);
+        box-shadow: 0 0 0 0 rgba(0, 255, 110, 0.7); /* Emerald-400 */
+    }
+    70% {
+        transform: scale(1.02);
+        box-shadow: 0 0 10px 10px rgba(0, 255, 110, 0.5); /* Emerald-400 transparent */
+    }
+    100% {
+        transform: scale(1);
+        box-shadow: 0 0 0 0 rgba(0, 255, 110, 0.2);
+    }
+}
+
+/* --- Style for winning cells --- */
+.bingo-cell.win-cell {
+    /* Apply a distinct border to indicate win */
+    border-color: #10b981; /* Emerald-500 */
+    border-width: 3px; /* Make border more prominent */
+    animation: pulse 1.5s infinite;
+    z-index: 15; /* Ensure winning cells are on top of highlighted/others */
+    /* Optional: Slightly different background tint? */
+    /* Example: background-color: rgba(16, 185, 129, 0.1); /* Light emerald tint */
+}
+
+/* Ensure winning cell text is still readable over potential background tint */
+.bingo-cell.win-cell .bingo-cell-text {
+    z-index: 16; /* Keep text above the cell's base styles/animations */
+}
diff --git a/beango/index.html b/beango/index.html
index 2170c70..7948308 100644
--- a/beango/index.html
+++ b/beango/index.html
@@ -5,7 +5,7 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>Beango!</title>
     <script src="https://cdn.tailwindcss.com"></script>
-    <link rel="stylesheet" href="css/beango.css?v=1.0.3">
+    <link rel="stylesheet" href="css/beango.css?v=1.0.4">
     <link rel="icon" type="image/svg+xml" href="/bean.svg">
 </head>
 <body class="flex flex-col items-center justify-center p-4 font-sans relative">
@@ -439,7 +439,7 @@
         </div>
     </div>
 
-    <script type="module" src="js/beango.js?v=1.0.2"></script>
+    <script type="module" src="js/beango.js?v=1.0.3"></script>
     <script type="module">
         import { toggleConfig, exportSettings, importSettings, resetAllSettings, explodeBeans, randomizeBoard, clearMarks, generateBoard, resetSettings } from './js/beango.js';
         window.explodeBeans = explodeBeans;
diff --git a/beango/js/beango.js b/beango/js/beango.js
index 4d56aca..3da00ba 100644
--- a/beango/js/beango.js
+++ b/beango/js/beango.js
@@ -231,6 +231,8 @@ function refreshMarkedCellStyles() {
     markedCells.forEach(cell => {
         applyMarkedCellStyle(cell); // Re-apply based on current settings
     });
+    // After refreshing marked styles, check for wins
+    checkWinConditions();
 }
 
 // --- Save current header settings to localStorage ---
@@ -726,6 +728,7 @@ export function randomizeBoard() {
 
     clearSearch(); // Clear search highlights and input
     clearMarks(false); // Clear visual marks
+    checkWinConditions(); // Check for wins after randomization (should be none)
     saveBoardState(); // Save the new randomized state (including cleared marks)
     showNotification('Board randomized!', 'success');
 }
@@ -734,6 +737,7 @@ function selectCell(cell) {
     cell.classList.toggle("marked"); // Toggle the dedicated 'marked' class
     applyMarkedCellStyle(cell); // Apply/remove styles based on new state and settings
     saveBoardState(); // RE-ADD: Save updated marks immediately after click
+    checkWinConditions(); // Check for wins after a cell is selected/deselected
 }
 
 export function clearMarks(save = true) {
@@ -741,17 +745,19 @@ export function clearMarks(save = true) {
     cells.forEach(cell => {
         if (cell.classList.contains('marked')) {
             cell.classList.remove('marked');
-            // applyMarkedCellStyle(cell); // Redundant call removed
             // Apply default style ONLY to the cell just unmarked
             applyCellStyle(cell);
         }
-        // Ensure styles are reset even if class was somehow missing
-        // applyCellStyle(cell); // REMOVED Unconditional call
+        cell.classList.remove('win-cell'); // NEW: Remove win highlight
     });
+    // Remove win class from all cells, even unmarked ones
+    cells.forEach(cell => cell.classList.remove('win-cell'));
+
     if (save) {
         saveBoardState(); // Save cleared marks
         showNotification('Marks cleared.', 'info');
     }
+    // No need to call checkWinConditions here, as all marks are cleared
 }
 
 // Fisher-Yates (aka Knuth) Shuffle Algorithm
@@ -1494,8 +1500,106 @@ document.addEventListener('DOMContentLoaded', () => {
 
     // Equalize sizes as the very last step after all content and styles are set
     equalizeCellSizes(); // <-- MOVED HERE
+    // Check for win conditions after loading everything
+    checkWinConditions();
 });
 
+// --- Function to check win conditions ---
+function checkWinConditions() {
+    const board = document.getElementById('bingo-board');
+    if (!board) return;
+    const cells = board.querySelectorAll('.bingo-cell');
+    if (cells.length === 0) return; // No cells to check
+
+    const size = parseInt(localStorage.getItem(vars.LS_BOARD_SIZE) || '5', 10);
+    const markedIndices = getMarkedIndices(); // Get the indices of marked cells
+
+    if (markedIndices.length < size) { // Not enough marks for a win
+        // Ensure no win class remains if marks are removed below threshold
+        cells.forEach(cell => cell.classList.remove('win-cell'));
+        return;
+    }
+
+    const winningIndices = new Set();
+
+    // Create a representation of the board (e.g., 2D array or set)
+    const markedSet = new Set(markedIndices);
+
+    // Check Rows
+    for (let r = 0; r < size; r++) {
+        let rowWin = true;
+        const rowIndices = [];
+        for (let c = 0; c < size; c++) {
+            const index = r * size + c;
+            rowIndices.push(index);
+            if (!markedSet.has(index)) {
+                rowWin = false;
+                break;
+            }
+        }
+        if (rowWin) {
+            rowIndices.forEach(idx => winningIndices.add(idx));
+        }
+    }
+
+    // Check Columns
+    for (let c = 0; c < size; c++) {
+        let colWin = true;
+        const colIndices = [];
+        for (let r = 0; r < size; r++) {
+            const index = r * size + c;
+            colIndices.push(index);
+            if (!markedSet.has(index)) {
+                colWin = false;
+                break;
+            }
+        }
+        if (colWin) {
+            colIndices.forEach(idx => winningIndices.add(idx));
+        }
+    }
+
+    // Check Diagonal (Top-Left to Bottom-Right)
+    let diag1Win = true;
+    const diag1Indices = [];
+    for (let i = 0; i < size; i++) {
+        const index = i * size + i;
+        diag1Indices.push(index);
+        if (!markedSet.has(index)) {
+            diag1Win = false;
+            break;
+        }
+    }
+    if (diag1Win) {
+        diag1Indices.forEach(idx => winningIndices.add(idx));
+    }
+
+    // Check Diagonal (Top-Right to Bottom-Left)
+    let diag2Win = true;
+    const diag2Indices = [];
+    for (let i = 0; i < size; i++) {
+        const index = i * size + (size - 1 - i);
+        diag2Indices.push(index);
+        if (!markedSet.has(index)) {
+            diag2Win = false;
+            break;
+        }
+    }
+    if (diag2Win) {
+        diag2Indices.forEach(idx => winningIndices.add(idx));
+    }
+
+    // Apply 'win-cell' class
+    cells.forEach((cell, index) => {
+        if (winningIndices.has(index)) {
+            cell.classList.add('win-cell');
+        } else {
+            cell.classList.remove('win-cell');
+        }
+    });
+}
+
+
 // --- Settings Import/Export ---
 export function exportSettings() {
     const settingsToExport = {};
