diff --git a/pos/static/js/sidebar.js b/pos/static/js/sidebar.js
new file mode 100644
index 0000000..bb29643
--- /dev/null
+++ b/pos/static/js/sidebar.js
@@ -0,0 +1,167 @@
+/**
+ * sidebar.js — Shared sidebar component for all POS pages
+ *
+ * Injects a consistent sidebar into any page that has a <aside class="sidebar"> or
+ * <div id="pos-sidebar-container">. Overrides the page's own sidebar content
+ * with a standardized navigation.
+ */
+(function() {
+    'use strict';
+
+    var employee = window.POS_USER || {};
+    var name = employee.name || 'Usuario';
+    var roleLabel = employee.roleLabel || '';
+    var initials = employee.initials || '?';
+    var currentPath = window.location.pathname;
+
+    var navItems = [
+        { label: 'Dashboard',     icon: '📊', href: '/pos/dashboard' },
+        { label: 'Punto de Venta', icon: '💰', href: '/pos/sale' },
+        { label: 'Catálogo',      icon: '📦', href: '/pos/catalog' },
+        { label: 'Inventario',    icon: '📋', href: '/pos/inventory' },
+        { label: 'Clientes',      icon: '👥', href: '/pos/customers' },
+        { label: 'Facturación',   icon: '🧾', href: '/pos/invoicing' },
+        { label: 'Contabilidad',  icon: '📒', href: '/pos/accounting' },
+        { label: 'Reportes',      icon: '📈', href: '/pos/reports' },
+        { label: 'Configuración', icon: '⚙️', href: '/pos/config' },
+    ];
+
+    // Build sidebar HTML
+    var linksHtml = navItems.map(function(item) {
+        var isActive = currentPath === item.href;
+        var cls = 'pos-nav__item' + (isActive ? ' is-active' : '');
+        return '<a class="' + cls + '" href="' + item.href + '">'
+            + '<span class="pos-nav__icon">' + item.icon + '</span>'
+            + '<span class="pos-nav__label">' + item.label + '</span>'
+            + '</a>';
+    }).join('');
+
+    var sidebarHtml = ''
+        + '<div class="pos-sidebar__brand">'
+        + '  <div class="pos-sidebar__logo">N</div>'
+        + '  <div class="pos-sidebar__title">Nexus POS</div>'
+        + '</div>'
+        + '<nav class="pos-sidebar__nav">' + linksHtml + '</nav>'
+        + '<div class="pos-sidebar__footer">'
+        + '  <div class="pos-sidebar__user">'
+        + '    <div class="pos-sidebar__avatar">' + initials + '</div>'
+        + '    <div class="pos-sidebar__user-info">'
+        + '      <div class="pos-sidebar__user-name">' + name + '</div>'
+        + '      <div class="pos-sidebar__user-role">' + roleLabel + '</div>'
+        + '    </div>'
+        + '  </div>'
+        + '  <button class="pos-sidebar__logout" onclick="posLogout()" title="Cerrar sesión">⏻</button>'
+        + '</div>';
+
+    // Inject CSS
+    var css = document.createElement('style');
+    css.textContent = ''
+        + '.pos-sidebar {'
+        + '  position: fixed; top: 0; left: 0; bottom: 0; width: 220px;'
+        + '  background: var(--color-bg-elevated, #161B22);'
+        + '  border-right: 1px solid var(--color-border, #30363D);'
+        + '  display: flex; flex-direction: column;'
+        + '  z-index: 100; overflow-y: auto;'
+        + '  font-family: var(--font-body, sans-serif);'
+        + '  transition: background-color 0.3s;'
+        + '}'
+        + '.pos-sidebar__brand {'
+        + '  display: flex; align-items: center; gap: 10px;'
+        + '  padding: 16px 16px 12px; border-bottom: 1px solid var(--color-border, #30363D);'
+        + '}'
+        + '.pos-sidebar__logo {'
+        + '  width: 36px; height: 36px; border-radius: 8px;'
+        + '  background: var(--color-primary, #F5A623); color: #fff;'
+        + '  display: flex; align-items: center; justify-content: center;'
+        + '  font-weight: 800; font-size: 1.1rem;'
+        + '}'
+        + '.pos-sidebar__title {'
+        + '  font-weight: 700; font-size: 1rem;'
+        + '  color: var(--color-text-primary, #E6EDF3);'
+        + '}'
+        + '.pos-sidebar__nav {'
+        + '  flex: 1; padding: 8px 8px; display: flex; flex-direction: column; gap: 2px;'
+        + '}'
+        + '.pos-nav__item {'
+        + '  display: flex; align-items: center; gap: 10px;'
+        + '  padding: 9px 12px; border-radius: 6px;'
+        + '  color: var(--color-text-secondary, #8B949E);'
+        + '  text-decoration: none; font-size: 0.88rem; font-weight: 500;'
+        + '  transition: all 0.15s;'
+        + '}'
+        + '.pos-nav__item:hover {'
+        + '  background: var(--color-bg-base, rgba(255,255,255,0.05));'
+        + '  color: var(--color-text-primary, #E6EDF3);'
+        + '}'
+        + '.pos-nav__item.is-active {'
+        + '  background: var(--color-primary, #F5A623);'
+        + '  color: #fff; font-weight: 600;'
+        + '}'
+        + '.pos-nav__icon { font-size: 1rem; width: 20px; text-align: center; }'
+        + '.pos-nav__label { white-space: nowrap; }'
+        + '.pos-sidebar__footer {'
+        + '  padding: 12px; border-top: 1px solid var(--color-border, #30363D);'
+        + '  display: flex; align-items: center; justify-content: space-between;'
+        + '}'
+        + '.pos-sidebar__user {'
+        + '  display: flex; align-items: center; gap: 8px;'
+        + '}'
+        + '.pos-sidebar__avatar {'
+        + '  width: 32px; height: 32px; border-radius: 50%;'
+        + '  background: var(--color-primary, #F5A623); color: #fff;'
+        + '  display: flex; align-items: center; justify-content: center;'
+        + '  font-size: 0.75rem; font-weight: 700;'
+        + '}'
+        + '.pos-sidebar__user-name {'
+        + '  font-size: 0.82rem; font-weight: 600;'
+        + '  color: var(--color-text-primary, #E6EDF3);'
+        + '}'
+        + '.pos-sidebar__user-role {'
+        + '  font-size: 0.7rem; color: var(--color-text-muted, #6a6a7a);'
+        + '}'
+        + '.pos-sidebar__logout {'
+        + '  background: none; border: 1px solid var(--color-border, #30363D);'
+        + '  color: var(--color-text-muted, #6a6a7a); border-radius: 6px;'
+        + '  padding: 6px 8px; cursor: pointer; font-size: 1rem;'
+        + '  transition: all 0.15s;'
+        + '}'
+        + '.pos-sidebar__logout:hover {'
+        + '  color: var(--color-error, #F85149);'
+        + '  border-color: var(--color-error, #F85149);'
+        + '}'
+        + '/* Push main content right */'
+        + '.pos-main-offset { margin-left: 220px; }'
+        + '@media (max-width: 768px) {'
+        + '  .pos-sidebar { width: 60px; }'
+        + '  .pos-nav__label, .pos-sidebar__title,'
+        + '  .pos-sidebar__user-info { display: none; }'
+        + '  .pos-sidebar__footer { justify-content: center; }'
+        + '  .pos-sidebar__user { justify-content: center; }'
+        + '  .pos-main-offset { margin-left: 60px; }'
+        + '}';
+    document.head.appendChild(css);
+
+    // Find or create sidebar container
+    // Strategy: replace existing sidebar content or create new one
+    var existingSidebar = document.querySelector('aside.sidebar, .sidebar, #sidebar');
+
+    if (existingSidebar) {
+        // Replace existing sidebar content
+        existingSidebar.className = 'pos-sidebar';
+        existingSidebar.innerHTML = sidebarHtml;
+        existingSidebar.removeAttribute('style');
+    } else {
+        // Create new sidebar
+        var sidebar = document.createElement('aside');
+        sidebar.className = 'pos-sidebar';
+        sidebar.innerHTML = sidebarHtml;
+        document.body.insertBefore(sidebar, document.body.firstChild);
+    }
+
+    // Add offset class to main content
+    var mainContent = document.querySelector('main, .main-content, #mainContent, .page-content');
+    if (mainContent) {
+        mainContent.classList.add('pos-main-offset');
+    }
+
+})();
diff --git a/pos/templates/accounting.html b/pos/templates/accounting.html
index 65e4577..16b0c24 100644
--- a/pos/templates/accounting.html
+++ b/pos/templates/accounting.html
@@ -2250,6 +2250,7 @@
   </div><!-- /app-shell -->
 
   <script src="/pos/static/js/app-init.js"></script>
+  <script src="/pos/static/js/sidebar.js"></script>
   <script src="/pos/static/js/accounting.js"></script>
 
 </body>
diff --git a/pos/templates/catalog.html b/pos/templates/catalog.html
index 2031699..5a26b68 100644
--- a/pos/templates/catalog.html
+++ b/pos/templates/catalog.html
@@ -2138,6 +2138,7 @@
   </div>
 
   <script src="/pos/static/js/app-init.js"></script>
+  <script src="/pos/static/js/sidebar.js"></script>
   <script src="/pos/static/js/catalog.js"></script>
   <script src="/pos/static/js/offline-banner.js"></script>
 </body>
diff --git a/pos/templates/config.html b/pos/templates/config.html
index ad89792..b1f4460 100644
--- a/pos/templates/config.html
+++ b/pos/templates/config.html
@@ -1821,6 +1821,7 @@
   </div><!-- /app-shell -->
 
   <script src="/pos/static/js/app-init.js"></script>
+  <script src="/pos/static/js/sidebar.js"></script>
   <script src="/pos/static/js/config.js"></script>
 
 </body>
diff --git a/pos/templates/customers.html b/pos/templates/customers.html
index 8f73d13..9d34410 100644
--- a/pos/templates/customers.html
+++ b/pos/templates/customers.html
@@ -2145,6 +2145,7 @@
   </div>
 
   <script src="/pos/static/js/app-init.js"></script>
+  <script src="/pos/static/js/sidebar.js"></script>
   <script src="/pos/static/js/customers.js"></script>
   <script src="/pos/static/js/offline-banner.js"></script>
 </body>
diff --git a/pos/templates/dashboard.html b/pos/templates/dashboard.html
index 55279f5..588196f 100644
--- a/pos/templates/dashboard.html
+++ b/pos/templates/dashboard.html
@@ -1949,6 +1949,7 @@
 
 
   <script src="/pos/static/js/app-init.js"></script>
+  <script src="/pos/static/js/sidebar.js"></script>
   <script src="/pos/static/js/dashboard.js"></script>
 
 </body>
diff --git a/pos/templates/inventory.html b/pos/templates/inventory.html
index 95b566d..165279e 100644
--- a/pos/templates/inventory.html
+++ b/pos/templates/inventory.html
@@ -2523,6 +2523,7 @@
   </div>
 
   <script src="/pos/static/js/app-init.js"></script>
+  <script src="/pos/static/js/sidebar.js"></script>
   <script src="/pos/static/js/inventory.js"></script>
   <script src="/pos/static/js/offline-banner.js"></script>
 </body>
diff --git a/pos/templates/invoicing.html b/pos/templates/invoicing.html
index b2dc43a..869431c 100644
--- a/pos/templates/invoicing.html
+++ b/pos/templates/invoicing.html
@@ -2699,6 +2699,7 @@
   </div>
 
   <script src="/pos/static/js/app-init.js"></script>
+  <script src="/pos/static/js/sidebar.js"></script>
   <script src="/pos/static/js/invoicing.js"></script>
 
 </body>
diff --git a/pos/templates/reports.html b/pos/templates/reports.html
index 9cc4e3f..219d4d3 100644
--- a/pos/templates/reports.html
+++ b/pos/templates/reports.html
@@ -2915,6 +2915,7 @@
   <!-- End app-shell -->
 
   <script src="/pos/static/js/app-init.js"></script>
+  <script src="/pos/static/js/sidebar.js"></script>
   <script src="/pos/static/js/reports.js"></script>
 
 </body>