diff --git a/src/components/Layout.tsx b/src/components/Layout.tsx
index cbda0ee..2c93a7e 100644
--- a/src/components/Layout.tsx
+++ b/src/components/Layout.tsx
@@ -1,11 +1,18 @@
 import React from 'react';
 import { Navigation } from './Navigation';
+import { useStore } from '../store/useStore';
+import { useDisplay } from '../hooks/useDisplay';
 
 export const Layout: React.FC<{ children: React.ReactNode }> = ({ children }) => {
+  const { isRailExpanded } = useStore();
+  const { navMode } = useDisplay();
+  
+  const isExpanded = navMode === 'rail-expanded' && isRailExpanded;
+
   return (
     <div className="app-container">
       <Navigation />
-      <main className="main-content">
+      <main className={`main-content ${isExpanded ? 'with-expanded-rail' : ''}`}>
         {children}
       </main>
     </div>
diff --git a/src/components/Navigation.tsx b/src/components/Navigation.tsx
index 5395601..fee1d9b 100644
--- a/src/components/Navigation.tsx
+++ b/src/components/Navigation.tsx
@@ -1,37 +1,84 @@
-import React from 'react';
+import React, { useState } from 'react';
 import { NavLink } from 'react-router-dom';
-import { User, Calendar, GraduationCap, MessageSquare, Settings } from 'lucide-react';
+import { 
+  Calendar, 
+  GraduationCap, 
+  FileText, 
+  MessageSquare, 
+  User, 
+  ChevronDown, 
+  ChevronRight,
+  Menu
+} from 'lucide-react';
+import { useStore } from '../store/useStore';
+import { useDisplay } from '../hooks/useDisplay';
+import { useScrollDirection } from '../hooks/useScrollDirection';
 
-const navItems = [
-  { path: '/profile', label: 'Profile', icon: User },
-  { path: '/schedule', label: 'Schedule', icon: Calendar },
-  { path: '/grades', label: 'Grades', icon: GraduationCap },
-  { path: '/messages', label: 'Messages', icon: MessageSquare },
-  { path: '/settings', label: 'Settings', icon: Settings },
+interface NavItem {
+  path: string;
+  label: string;
+  icon: any;
+  iconFilled: any;
+  badgeKey?: 'messages';
+  children?: { path: string; label: string }[];
+}
+
+const navItems: NavItem[] = [
+  { path: '/profile', label: 'Профиль', icon: User, iconFilled: User },
+  { 
+    path: '/schedule', 
+    label: 'Расписание', 
+    icon: Calendar, 
+    iconFilled: Calendar,
+    children: [
+      { path: '/schedule/week', label: 'Текущая неделя' },
+      { path: '/schedule/session', label: 'Сессия' },
+    ]
+  },
+  { 
+    path: '/grades', 
+    label: 'Успеваемость', 
+    icon: GraduationCap, 
+    iconFilled: GraduationCap,
+    children: [
+      { path: '/grades/list', label: 'Оценки' },
+      { path: '/grades/statements', label: 'Ведомости' },
+    ]
+  },
+  { 
+    path: '/docs', 
+    label: 'Документы', 
+    icon: FileText, 
+    iconFilled: FileText,
+    children: [
+      { path: '/docs/certs', label: 'Справки' },
+      { path: '/docs/apps', label: 'Заявления' },
+    ]
+  },
+  { path: '/messages', label: 'Сообщения', icon: MessageSquare, iconFilled: MessageSquare, badgeKey: 'messages' },
 ];
 
 export const Navigation: React.FC = () => {
-  return (
-    <>
-      <nav className="navigation-rail">
-        <div style={{ flex: 1, display: 'flex', flexDirection: 'column', gap: '12px' }}>
-          {navItems.map((item) => (
-            <NavLink
-              key={item.path}
-              to={item.path}
-              className={({ isActive }) => `nav-item ${isActive ? 'active' : ''}`}
-            >
-              <div className="nav-item-icon-wrapper">
-                <item.icon size={24} />
-              </div>
-              <span className="nav-item-label">{item.label}</span>
-            </NavLink>
-          ))}
-        </div>
-      </nav>
+  const { navMode } = useDisplay();
+  const { isRailExpanded, toggleRail, badges } = useStore();
+  const scrollDir = useScrollDirection();
+  const [expandedItems, setExpandedItems] = useState<string[]>([]);
 
-      <nav className="navigation-bar">
-        {navItems.map((item) => (
+  const toggleSubmenu = (label: string) => {
+    setExpandedItems(prev => 
+      prev.includes(label) ? prev.filter(i => i !== label) : [...prev, label]
+    );
+  };
+
+  const renderBadge = (count?: number) => {
+    if (!count) return null;
+    return <span className="m3-badge">{count > 99 ? '99+' : count}</span>;
+  };
+
+  if (navMode === 'bar') {
+    return (
+      <nav className={`navigation-bar ${scrollDir === 'down' ? 'hidden' : ''}`}>
+        {navItems.slice(0, 5).map((item) => (
           <NavLink
             key={item.path}
             to={item.path}
@@ -39,11 +86,71 @@ export const Navigation: React.FC = () => {
           >
             <div className="nav-item-icon-wrapper">
               <item.icon size={24} />
+              {item.badgeKey && renderBadge(badges[item.badgeKey])}
             </div>
             <span className="nav-item-label">{item.label}</span>
           </NavLink>
         ))}
       </nav>
-    </>
+    );
+  }
+
+  const isExpanded = navMode === 'rail-expanded' && isRailExpanded;
+
+  return (
+    <nav className={`navigation-rail ${isExpanded ? 'expanded' : ''}`}>
+      <div className="rail-header">
+        <button className="icon-button" onClick={toggleRail}>
+          <Menu size={24} />
+        </button>
+        {isExpanded && <span className="rail-title">Bonch</span>}
+      </div>
+
+      <div className="rail-items">
+        {navItems.map((item) => {
+          const hasChildren = item.children && item.children.length > 0;
+          const isItemExpanded = expandedItems.includes(item.label);
+
+          return (
+            <div key={item.label} className="nav-group">
+              <NavLink
+                to={item.path}
+                className={({ isActive }) => `nav-item ${isActive ? 'active' : ''}`}
+                onClick={() => {
+                  if (hasChildren && isExpanded) {
+                    toggleSubmenu(item.label);
+                  }
+                }}
+              >
+                <div className="nav-item-icon-wrapper">
+                  <item.icon size={24} />
+                  {item.badgeKey && renderBadge(badges[item.badgeKey])}
+                </div>
+                {isExpanded && <span className="nav-item-label">{item.label}</span>}
+                {isExpanded && hasChildren && (
+                  <div className="submenu-arrow">
+                    {isItemExpanded ? <ChevronDown size={16} /> : <ChevronRight size={16} />}
+                  </div>
+                )}
+              </NavLink>
+
+              {isExpanded && isItemExpanded && hasChildren && (
+                <div className="submenu">
+                  {item.children!.map(child => (
+                    <NavLink 
+                      key={child.path} 
+                      to={child.path} 
+                      className={({ isActive }) => `submenu-item ${isActive ? 'active' : ''}`}
+                    >
+                      {child.label}
+                    </NavLink>
+                  ))}
+                </div>
+              )}
+            </div>
+          );
+        })}
+      </div>
+    </nav>
   );
 };
diff --git a/src/hooks/useDisplay.ts b/src/hooks/useDisplay.ts
new file mode 100644
index 0000000..0215705
--- /dev/null
+++ b/src/hooks/useDisplay.ts
@@ -0,0 +1,19 @@
+import { useState, useEffect, useMemo } from 'react';
+
+export function useDisplay() {
+  const [width, setWidth] = useState(window.innerWidth);
+
+  useEffect(() => {
+    const handleResize = () => setWidth(window.innerWidth);
+    window.addEventListener('resize', handleResize);
+    return () => window.removeEventListener('resize', handleResize);
+  }, []);
+
+  const navMode = useMemo(() => {
+    if (width < 600) return 'bar';
+    if (width < 1240) return 'rail';
+    return 'rail-expanded';
+  }, [width]);
+
+  return { width, navMode };
+}
diff --git a/src/hooks/useScrollDirection.ts b/src/hooks/useScrollDirection.ts
new file mode 100644
index 0000000..09d60a7
--- /dev/null
+++ b/src/hooks/useScrollDirection.ts
@@ -0,0 +1,23 @@
+import { useState, useEffect } from 'react';
+
+export function useScrollDirection() {
+  const [scrollDir, setScrollDirection] = useState<'up' | 'down'>('up');
+
+  useEffect(() => {
+    let lastScrollY = window.pageYOffset;
+
+    const updateScrollDirection = () => {
+      const scrollY = window.pageYOffset;
+      const direction = scrollY > lastScrollY ? 'down' : 'up';
+      if (direction !== scrollDir && (scrollY - lastScrollY > 10 || scrollY - lastScrollY < -10)) {
+        setScrollDirection(direction);
+      }
+      lastScrollY = scrollY > 0 ? scrollY : 0;
+    };
+
+    window.addEventListener('scroll', updateScrollDirection);
+    return () => window.removeEventListener('scroll', updateScrollDirection);
+  }, [scrollDir]);
+
+  return scrollDir;
+}
diff --git a/src/store/useStore.ts b/src/store/useStore.ts
index e3a4d6b..03cdd31 100644
--- a/src/store/useStore.ts
+++ b/src/store/useStore.ts
@@ -7,11 +7,18 @@ interface AppState {
   isMockMode: boolean;
   theme: 'system' | 'light' | 'dark';
   seedColor: string;
+  isRailExpanded: boolean;
+  badges: {
+    messages: number;
+  };
   setApiDomain: (domain: string) => void;
   setApiKey: (key: string) => void;
   setMockMode: (isMock: boolean) => void;
   setTheme: (theme: 'system' | 'light' | 'dark') => void;
   setSeedColor: (color: string) => void;
+  toggleRail: () => void;
+  setRailExpanded: (expanded: boolean) => void;
+  setBadge: (key: keyof AppState['badges'], count: number) => void;
   reset: () => void;
 }
 
@@ -22,12 +29,21 @@ export const useStore = create<AppState>()(
       apiKey: '',
       isMockMode: import.meta.env.VITE_MOCK_MODE === 'true',
       theme: 'system',
-      seedColor: '#0061a4', // Default M3 Blue
+      seedColor: '#0061a4',
+      isRailExpanded: true,
+      badges: {
+        messages: 3, // Mock value
+      },
       setApiDomain: (apiDomain) => set({ apiDomain }),
       setApiKey: (apiKey) => set({ apiKey }),
       setMockMode: (isMockMode) => set({ isMockMode }),
       setTheme: (theme) => set({ theme }),
       setSeedColor: (seedColor) => set({ seedColor }),
+      toggleRail: () => set((state) => ({ isRailExpanded: !state.isRailExpanded })),
+      setRailExpanded: (isRailExpanded) => set({ isRailExpanded }),
+      setBadge: (key, count) => set((state) => ({ 
+        badges: { ...state.badges, [key]: count } 
+      })),
       reset: () => set({ apiKey: '' }),
     }),
     {
diff --git a/src/styles/globals.css b/src/styles/globals.css
index 20efa98..d811772 100644
--- a/src/styles/globals.css
+++ b/src/styles/globals.css
@@ -14,8 +14,9 @@
   --md-sys-color-outline: #73777f;
   --md-sys-color-error: #ba1a1a;
   
-  --nav-width: 80px;
-  --bottom-nav-height: 80px;
+  --nav-rail-width: 80px;
+  --nav-rail-expanded-width: 280px;
+  --nav-bar-height: 80px;
 }
 
 :root.dark {
@@ -49,7 +50,41 @@ body {
   transition: background-color 0.3s, color 0.3s;
 }
 
-/* Material 3 Components */
+/* M3 Components */
+
+.m3-badge {
+  position: absolute;
+  top: -4px;
+  right: -4px;
+  background-color: var(--md-sys-color-error);
+  color: white;
+  font-size: 10px;
+  font-weight: 500;
+  min-width: 16px;
+  height: 16px;
+  border-radius: 8px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  padding: 0 4px;
+}
+
+.icon-button {
+  width: 48px;
+  height: 48px;
+  border-radius: 24px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background: transparent;
+  border: none;
+  color: var(--md-sys-color-on-surface-variant);
+  transition: background-color 0.2s;
+}
+
+.icon-button:hover {
+  background-color: var(--md-sys-color-surface-variant);
+}
 
 .m3-button {
   display: inline-flex;
@@ -65,6 +100,7 @@ body {
   transition: box-shadow 0.2s, background-color 0.2s;
   background-color: transparent;
   color: var(--md-sys-color-primary);
+  text-decoration: none;
 }
 
 .m3-button-filled {
@@ -97,12 +133,7 @@ body {
   margin-bottom: 16px;
 }
 
-.m3-text-field:focus {
-  outline: none;
-  border-bottom: 2px solid var(--md-sys-color-primary);
-}
-
-/* Layout and Navigation */
+/* Layout */
 
 .app-container {
   display: flex;
@@ -111,59 +142,107 @@ body {
 
 .main-content {
   flex: 1;
-  padding-bottom: var(--bottom-nav-height);
+  padding: 16px;
 }
 
-@media (min-width: 600px) {
-  .main-content {
-    padding-bottom: 0;
-    margin-left: var(--nav-width);
-  }
-}
-
-.navigation-rail {
-  position: fixed;
-  left: 0;
-  top: 0;
-  bottom: 0;
-  width: var(--nav-width);
-  background-color: var(--md-sys-color-surface);
-  display: flex;
-  flex-direction: column;
-  align-items: center;
-  padding: 16px 0;
-  border-right: 1px solid var(--md-sys-color-outline);
-  z-index: 100;
-}
+/* Navigation Bar (Mobile) */
 
 .navigation-bar {
   position: fixed;
   left: 0;
   right: 0;
   bottom: 0;
-  height: var(--bottom-nav-height);
+  height: var(--nav-bar-height);
   background-color: var(--md-sys-color-surface-variant);
   display: flex;
   justify-content: space-around;
   align-items: center;
   padding: 0 8px;
   z-index: 100;
+  transition: transform 0.2s ease-in-out;
 }
 
+.navigation-bar.hidden {
+  transform: translateY(100%);
+}
+
+@media (min-width: 600px) {
+  .navigation-bar { display: none; }
+  .main-content { margin-left: var(--nav-rail-width); }
+}
+
+@media (min-width: 1240px) {
+  .main-content.with-expanded-rail { margin-left: var(--nav-rail-expanded-width); }
+}
+
+@media (max-width: 599px) {
+  .main-content { padding-bottom: calc(var(--nav-bar-height) + 16px); }
+}
+
+/* Navigation Rail (Tablet/Desktop) */
+
+.navigation-rail {
+  position: fixed;
+  left: 0;
+  top: 0;
+  bottom: 0;
+  width: var(--nav-rail-width);
+  background-color: var(--md-sys-color-surface);
+  display: flex;
+  flex-direction: column;
+  padding: 16px 0;
+  border-right: 1px solid var(--md-sys-color-outline);
+  z-index: 100;
+  transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
+  overflow-x: hidden;
+}
+
+.navigation-rail.expanded {
+  width: var(--nav-rail-expanded-width);
+}
+
+.rail-header {
+  display: flex;
+  align-items: center;
+  padding: 0 16px;
+  height: 56px;
+  gap: 12px;
+  margin-bottom: 8px;
+}
+
+.rail-title {
+  font-size: 20px;
+  font-weight: 500;
+  white-space: nowrap;
+}
+
+.rail-items {
+  display: flex;
+  flex-direction: column;
+  gap: 4px;
+}
+
+/* Nav Items Shared */
+
 .nav-item {
   display: flex;
-  flex-direction: column;
   align-items: center;
-  justify-content: center;
   text-decoration: none;
   color: var(--md-sys-color-on-surface-variant);
-  gap: 4px;
-  flex: 1;
-  height: 100%;
-  border-radius: 16px;
+  height: 56px;
+  padding: 0 12px;
+  position: relative;
   transition: background-color 0.2s;
 }
 
+.navigation-bar .nav-item {
+  flex-direction: column;
+  justify-content: center;
+  flex: 1;
+  gap: 4px;
+  padding: 0;
+}
+
 .nav-item-icon-wrapper {
   width: 64px;
   height: 32px;
@@ -172,6 +251,7 @@ body {
   justify-content: center;
   border-radius: 16px;
   transition: background-color 0.2s;
+  position: relative;
 }
 
 .nav-item.active .nav-item-icon-wrapper {
@@ -182,16 +262,47 @@ body {
 .nav-item-label {
   font-size: 12px;
   font-weight: 500;
+  white-space: nowrap;
 }
 
-@media (min-width: 600px) {
-  .navigation-bar {
-    display: none;
-  }
+.navigation-rail.expanded .nav-item {
+  height: 56px;
+  border-radius: 28px;
+  margin: 0 12px;
 }
 
-@media (max-width: 599px) {
-  .navigation-rail {
-    display: none;
-  }
+.navigation-rail.expanded .nav-item-label {
+  font-size: 14px;
+  margin-left: 12px;
+  flex: 1;
+}
+
+/* Submenu */
+
+.submenu {
+  display: flex;
+  flex-direction: column;
+  padding-left: 56px;
+  margin-bottom: 8px;
+}
+
+.submenu-item {
+  height: 48px;
+  display: flex;
+  align-items: center;
+  text-decoration: none;
+  color: var(--md-sys-color-on-surface-variant);
+  font-size: 14px;
+  border-radius: 24px;
+  margin: 0 12px;
+  padding: 0 16px;
+}
+
+.submenu-item.active {
+  background-color: var(--md-sys-color-secondary-container);
+  color: var(--md-sys-color-on-secondary-container);
+}
+
+.submenu-arrow {
+  margin-right: 8px;
 }