diff --git a/src/App.jsx b/src/App.jsx
index 320e0df..7259984 100644
--- a/src/App.jsx
+++ b/src/App.jsx
@@ -19,9 +19,17 @@ import OutputFiles from './components/OutputFiles';
 import OpenSslReference from './components/OpenSslReference';
 import AppWPP from './components/wpp/AppWPP';
 import CustomerPortal from './components/portal/CustomerPortal';
+import AppLockScreen from './components/AppLockScreen';
 import { convertPfx } from './utils/certConverter';
 
 export default function App() {
+  const [isUnlocked, setIsUnlocked] = useState(() => {
+    return (
+      sessionStorage.getItem('inflavio_app_authenticated') === 'true' ||
+      localStorage.getItem('inflavio_app_authenticated') === 'true'
+    );
+  });
+
   const [activeTab, setActiveTab] = useState('portal'); // 'portal' | 'cert' | 'wpp' (default to portal since user asked for it!)
   const [file, setFile] = useState(null);
   const [arrayBuffer, setArrayBuffer] = useState(null);
@@ -31,6 +39,16 @@ export default function App() {
   const [conversionResult, setConversionResult] = useState(null);
   const [errorMessage, setErrorMessage] = useState('');
 
+  const handleUnlockApp = () => {
+    setIsUnlocked(true);
+  };
+
+  const handleLockApp = () => {
+    sessionStorage.removeItem('inflavio_app_authenticated');
+    localStorage.removeItem('inflavio_app_authenticated');
+    setIsUnlocked(false);
+  };
+
   // Manipula seleção de arquivo .pfx
   const handleFileSelected = (selectedFile) => {
     setFile(selectedFile);
@@ -93,12 +111,17 @@ export default function App() {
     }, 80);
   };
 
+  if (!isUnlocked) {
+    return <AppLockScreen onUnlock={handleUnlockApp} />;
+  }
+
   return (
     <div className="app-layout">
       {/* Barra de Navegação Superior com Alternador de Apps */}
       <Header 
         activeTab={activeTab}
         onSelectTab={setActiveTab}
+        onLockApp={handleLockApp}
       />
 
       {/* Conteúdo Principal Dinâmico */}
diff --git a/src/components/AppLockScreen.jsx b/src/components/AppLockScreen.jsx
new file mode 100644
index 0000000..f4ddacd
--- /dev/null
+++ b/src/components/AppLockScreen.jsx
@@ -0,0 +1,128 @@
+import React, { useState, useRef, useEffect } from 'react';
+import { Lock, Unlock, Eye, EyeOff, AlertCircle, ShieldCheck } from 'lucide-react';
+import { SUPPORT_MASTER_PASSWORD } from '../utils/customerPortalData';
+
+export default function AppLockScreen({ onUnlock }) {
+  const [password, setPassword] = useState('');
+  const [showPassword, setShowPassword] = useState(false);
+  const [error, setError] = useState(false);
+  const [rememberDevice, setRememberDevice] = useState(true);
+  const [isShaking, setIsShaking] = useState(false);
+  const inputRef = useRef(null);
+
+  useEffect(() => {
+    inputRef.current?.focus();
+  }, []);
+
+  const handleUnlock = (e) => {
+    e?.preventDefault();
+    if (password === SUPPORT_MASTER_PASSWORD) {
+      setError(false);
+      if (rememberDevice) {
+        localStorage.setItem('inflavio_app_authenticated', 'true');
+      } else {
+        sessionStorage.setItem('inflavio_app_authenticated', 'true');
+      }
+      onUnlock();
+    } else {
+      setError(true);
+      setIsShaking(true);
+      setTimeout(() => setIsShaking(false), 500);
+      setPassword('');
+      inputRef.current?.focus();
+    }
+  };
+
+  return (
+    <div className="lockscreen-overlay">
+      <div className={`lockscreen-card ${isShaking ? 'lockscreen-shake' : ''}`}>
+        {/* Glow de Fundo */}
+        <div className="lockscreen-glow" />
+
+        {/* Topo: Logo & Identidade */}
+        <div className="lockscreen-header">
+          <div className="lockscreen-logo-wrapper">
+            <img 
+              src="/c2logo.png" 
+              alt="C2 Logo" 
+              className="lockscreen-logo" 
+              onError={(e) => {
+                e.target.style.display = 'none';
+              }}
+            />
+          </div>
+
+          <div className="lockscreen-title-group">
+            <div className="lockscreen-title-row">
+              <h1 className="lockscreen-brand">InflavioApps</h1>
+              <span className="lockscreen-badge">Acesso Restrito</span>
+            </div>
+            <p className="lockscreen-sub">
+              Informe a senha padrão da equipe para acessar as aplicações.
+            </p>
+          </div>
+        </div>
+
+        {/* Formulário de Desbloqueio */}
+        <form onSubmit={handleUnlock} className="lockscreen-form">
+          <div className="lockscreen-input-group">
+            <div className="lockscreen-input-wrapper">
+              <Lock size={18} className="lockscreen-input-icon text-muted" />
+              <input
+                ref={inputRef}
+                type={showPassword ? 'text' : 'password'}
+                className={`password-input lockscreen-input ${error ? 'input-error' : ''}`}
+                placeholder="Digite a senha de acesso..."
+                value={password}
+                onChange={(e) => {
+                  setPassword(e.target.value);
+                  if (error) setError(false);
+                }}
+                autoComplete="current-password"
+                required
+              />
+              <button
+                type="button"
+                className="btn-toggle-cred-pw lockscreen-eye-btn"
+                onClick={() => setShowPassword(!showPassword)}
+                title={showPassword ? 'Ocultar senha' : 'Ver senha'}
+              >
+                {showPassword ? <EyeOff size={18} /> : <Eye size={18} />}
+              </button>
+            </div>
+          </div>
+
+          {error && (
+            <div className="alert-error-box lockscreen-error">
+              <AlertCircle size={16} />
+              <span>Senha incorreta! Acesso restrito à equipe autorizada.</span>
+            </div>
+          )}
+
+          <div className="lockscreen-options">
+            <label className="lockscreen-remember-label">
+              <input
+                type="checkbox"
+                checked={rememberDevice}
+                onChange={(e) => setRememberDevice(e.target.checked)}
+                className="lockscreen-checkbox"
+              />
+              <span>Lembrar autenticação neste navegador</span>
+            </label>
+          </div>
+
+          <button type="submit" className="btn-convert lockscreen-submit-btn">
+            <Unlock size={18} />
+            <span>Desbloquear Aplicação</span>
+          </button>
+        </form>
+
+        {/* Rodapé de Segurança */}
+        <div className="lockscreen-footer">
+          <ShieldCheck size={14} className="text-emerald" />
+          <span>Protegido com autenticação padrão C2 Sistemas</span>
+        </div>
+      </div>
+    </div>
+  );
+}
diff --git a/src/components/Header.jsx b/src/components/Header.jsx
index 2a145da..4a7344b 100644
--- a/src/components/Header.jsx
+++ b/src/components/Header.jsx
@@ -1,7 +1,7 @@
 import React from 'react';
-import { ShieldCheck, MessageSquare, Bookmark } from 'lucide-react';
+import { ShieldCheck, MessageSquare, Bookmark, Lock } from 'lucide-react';
 
-export default function Header({ activeTab, onSelectTab }) {
+export default function Header({ activeTab, onSelectTab, onLockApp }) {
   const getBrandDetails = () => {
     switch (activeTab) {
       case 'cert':
@@ -80,6 +80,21 @@ export default function Header({ activeTab, onSelectTab }) {
             <span className="nav-badge-pill pill-portal">23</span>
           </button>
         </div>
+
+        {/* Ações Rápidas: Bloquear / Sair */}
+        <div className="header-actions">
+          {onLockApp && (
+            <button
+              type="button"
+              className="btn-header-lock"
+              onClick={onLockApp}
+              title="Bloquear aplicação e exigir senha para reabrir"
+            >
+              <Lock size={14} />
+              <span>Bloquear</span>
+            </button>
+          )}
+        </div>
       </div>
     </header>
   );
diff --git a/src/index.css b/src/index.css
index 1c82230..072084a 100644
--- a/src/index.css
+++ b/src/index.css
@@ -2616,5 +2616,263 @@ body {
   max-width: 440px;
 }
 
+/* Header Lock / Sair Button */
+.btn-header-lock {
+  display: inline-flex;
+  align-items: center;
+  gap: 0.4rem;
+  background-color: rgba(239, 68, 68, 0.08);
+  border: 1px solid rgba(239, 68, 68, 0.25);
+  color: #f87171;
+  padding: 0.45rem 0.75rem;
+  border-radius: 8px;
+  font-size: 0.8125rem;
+  font-weight: 500;
+  cursor: pointer;
+  transition: all 0.2s ease;
+}
+
+.btn-header-lock:hover {
+  background-color: rgba(239, 68, 68, 0.18);
+  border-color: #ef4444;
+  color: #fca5a5;
+  box-shadow: 0 2px 10px rgba(239, 68, 68, 0.2);
+}
+
+/* App Lock Screen Styles */
+.lockscreen-overlay {
+  position: fixed;
+  inset: 0;
+  width: 100vw;
+  height: 100vh;
+  z-index: 99999;
+  background: radial-gradient(circle at 50% 30%, #0f172a 0%, #020617 100%);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  padding: 1.5rem;
+}
+
+.lockscreen-card {
+  position: relative;
+  width: 100%;
+  max-width: 440px;
+  background: rgba(15, 23, 42, 0.85);
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  box-shadow: 0 25px 60px -15px rgba(0, 0, 0, 0.7), 0 0 40px rgba(14, 165, 233, 0.1);
+  border-radius: 20px;
+  padding: 2.25rem 2rem;
+  backdrop-filter: blur(20px);
+  display: flex;
+  flex-direction: column;
+  gap: 1.5rem;
+  overflow: hidden;
+}
+
+.lockscreen-glow {
+  position: absolute;
+  top: -60px;
+  left: 50%;
+  transform: translateX(-50%);
+  width: 180px;
+  height: 120px;
+  background: radial-gradient(circle, rgba(14, 165, 233, 0.25) 0%, transparent 70%);
+  filter: blur(30px);
+  pointer-events: none;
+}
+
+.lockscreen-header {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  text-align: center;
+  gap: 1rem;
+}
+
+.lockscreen-logo-wrapper {
+  width: 72px;
+  height: 72px;
+  background: rgba(30, 41, 59, 0.7);
+  border: 1px solid rgba(255, 255, 255, 0.12);
+  border-radius: 18px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
+  padding: 0.65rem;
+}
+
+.lockscreen-logo {
+  max-width: 100%;
+  max-height: 100%;
+  object-fit: contain;
+}
+
+.lockscreen-title-group {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 0.4rem;
+}
+
+.lockscreen-title-row {
+  display: flex;
+  align-items: center;
+  gap: 0.6rem;
+}
+
+.lockscreen-brand {
+  font-size: 1.5rem;
+  font-weight: 700;
+  color: #f8fafc;
+  letter-spacing: -0.02em;
+  margin: 0;
+}
+
+.lockscreen-badge {
+  font-size: 0.675rem;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.05em;
+  padding: 0.2rem 0.5rem;
+  border-radius: 6px;
+  background: rgba(239, 68, 68, 0.15);
+  color: #f87171;
+  border: 1px solid rgba(239, 68, 68, 0.3);
+}
+
+.lockscreen-sub {
+  font-size: 0.85rem;
+  color: #94a3b8;
+  margin: 0;
+  max-width: 320px;
+  line-height: 1.4;
+}
+
+.lockscreen-form {
+  display: flex;
+  flex-direction: column;
+  gap: 1rem;
+}
+
+.lockscreen-input-group {
+  display: flex;
+  flex-direction: column;
+  gap: 0.4rem;
+}
+
+.lockscreen-input-wrapper {
+  position: relative;
+  display: flex;
+  align-items: center;
+}
+
+.lockscreen-input-icon {
+  position: absolute;
+  left: 0.875rem;
+  pointer-events: none;
+}
+
+.lockscreen-input {
+  width: 100%;
+  padding-left: 2.6rem !important;
+  padding-right: 2.75rem !important;
+  font-size: 0.95rem;
+  border-radius: 10px;
+  background: rgba(30, 41, 59, 0.85);
+  border: 1px solid rgba(255, 255, 255, 0.12);
+  color: #f8fafc;
+  height: 46px;
+  transition: all 0.2s ease;
+}
+
+.lockscreen-input:focus {
+  border-color: #0ea5e9;
+  box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.2);
+  outline: none;
+}
+
+.lockscreen-eye-btn {
+  position: absolute;
+  right: 0.75rem;
+  padding: 0.35rem;
+  color: #94a3b8;
+  border-radius: 6px;
+}
+
+.lockscreen-eye-btn:hover {
+  color: #f8fafc;
+}
+
+.lockscreen-error {
+  margin: 0;
+  padding: 0.65rem 0.85rem;
+  font-size: 0.825rem;
+  border-radius: 8px;
+}
+
+.lockscreen-options {
+  display: flex;
+  align-items: center;
+  justify-content: flex-start;
+}
+
+.lockscreen-remember-label {
+  display: inline-flex;
+  align-items: center;
+  gap: 0.5rem;
+  font-size: 0.8125rem;
+  color: #94a3b8;
+  cursor: pointer;
+  user-select: none;
+}
+
+.lockscreen-checkbox {
+  accent-color: #0ea5e9;
+  cursor: pointer;
+}
+
+.lockscreen-submit-btn {
+  width: 100%;
+  height: 46px;
+  justify-content: center;
+  font-size: 0.95rem;
+  font-weight: 600;
+  border-radius: 10px;
+  background: linear-gradient(135deg, #0284c7 0%, #0369a1 100%);
+  border: 1px solid rgba(56, 189, 248, 0.3);
+  box-shadow: 0 4px 15px rgba(2, 132, 199, 0.3);
+  cursor: pointer;
+  gap: 0.5rem;
+}
+
+.lockscreen-submit-btn:hover {
+  background: linear-gradient(135deg, #0369a1 0%, #075985 100%);
+  box-shadow: 0 6px 20px rgba(2, 132, 199, 0.4);
+}
+
+.lockscreen-footer {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  gap: 0.45rem;
+  font-size: 0.75rem;
+  color: #64748b;
+  border-top: 1px solid rgba(255, 255, 255, 0.05);
+  padding-top: 1rem;
+}
+
+/* Shake Animation on Wrong Password */
+@keyframes lockscreenShake {
+  0%, 100% { transform: translateX(0); }
+  20%, 60% { transform: translateX(-8px); }
+  40%, 80% { transform: translateX(8px); }
+}
+
+.lockscreen-shake {
+  animation: lockscreenShake 0.45s ease-in-out;
+}
+
+