diff --git a/aa-settings.h b/aa-settings.h
deleted file mode 100644
index 2713ea6..0000000
--- a/aa-settings.h
+++ /dev/null
@@ -1,674 +0,0 @@
-#ifndef SETTINGS_H
-#define SETTINGS_H
-
-const char settings_html PROGMEM = R"rawliteral(
-<!DOCTYPE html>
-<html>
-<head>
-    <meta charset="UTF-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
-    <title>Settings - Byun CAN Logger v2.5</title>
-    <style>
-        * { margin: 0; padding: 0; box-sizing: border-box; }
-        body {
-            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
-            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
-            min-height: 100vh;
-            padding: 10px;
-        }
-        .container {
-            max-width: 900px;
-            margin: 0 auto;
-            background: white;
-            border-radius: 15px;
-            box-shadow: 0 20px 60px rgba(0,0,0,0.3);
-            overflow: hidden;
-        }
-        .header {
-            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
-            color: white;
-            padding: 20px;
-            text-align: center;
-        }
-        .header h1 { font-size: 1.8em; margin-bottom: 5px; }
-        .header p { opacity: 0.9; font-size: 0.9em; }
-        .nav {
-            background: #2c3e50;
-            padding: 10px;
-            display: flex;
-            gap: 10px;
-            flex-wrap: wrap;
-            justify-content: center;
-        }
-        .nav a {
-            color: white;
-            text-decoration: none;
-            padding: 10px 15px;
-            border-radius: 5px;
-            transition: all 0.3s;
-            font-size: 0.9em;
-            white-space: nowrap;
-        }
-        .nav a:hover { background: #34495e; }
-        .nav a.active { background: #3498db; }
-        .content { padding: 25px; }
-        
-        .settings-section {
-            background: #f8f9fa;
-            padding: 25px;
-            border-radius: 10px;
-            margin-bottom: 20px;
-            box-shadow: 0 2px 8px rgba(0,0,0,0.05);
-            border: 2px solid #e0e0e0;
-        }
-        
-        .section-title {
-            color: #333;
-            font-size: 1.3em;
-            margin-bottom: 20px;
-            padding-bottom: 10px;
-            border-bottom: 3px solid #667eea;
-            display: flex;
-            align-items: center;
-            gap: 10px;
-        }
-        
-        .subsection-title {
-            color: #555;
-            font-size: 1.05em;
-            margin: 20px 0 15px 0;
-            font-weight: 700;
-            display: flex;
-            align-items: center;
-            gap: 8px;
-        }
-        
-        .form-group {
-            margin-bottom: 18px;
-        }
-        
-        .form-group:last-child {
-            margin-bottom: 0;
-        }
-        
-        label {
-            display: block;
-            font-weight: 600;
-            color: #333;
-            margin-bottom: 8px;
-            font-size: 0.95em;
-        }
-        
-        .help-text {
-            font-size: 0.85em;
-            color: #666;
-            margin-top: 5px;
-            line-height: 1.5;
-            padding-left: 5px;
-        }
-        
-        input[type="text"],
-        input[type="password"] {
-            width: 100%;
-            padding: 12px 15px;
-            border: 2px solid #e1e8ed;
-            border-radius: 8px;
-            font-size: 0.95em;
-            transition: all 0.3s;
-            background: white;
-            font-family: inherit;
-        }
-        
-        input[type="text"]:focus,
-        input[type="password"]:focus {
-            outline: none;
-            border-color: #667eea;
-            box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
-        }
-        
-        input[type="checkbox"] {
-            width: 20px;
-            height: 20px;
-            cursor: pointer;
-            margin-right: 10px;
-            accent-color: #667eea;
-        }
-        
-        .checkbox-group {
-            display: flex;
-            align-items: center;
-            margin-bottom: 12px;
-            padding: 10px;
-            background: white;
-            border-radius: 8px;
-            border: 2px solid #e1e8ed;
-            transition: all 0.3s;
-        }
-        
-        .checkbox-group:hover {
-            border-color: #667eea;
-        }
-        
-        .checkbox-group label {
-            margin-bottom: 0;
-            cursor: pointer;
-            user-select: none;
-            flex: 1;
-        }
-        
-        .sta-settings {
-            background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
-            padding: 20px;
-            border-radius: 8px;
-            margin-top: 15px;
-            border-left: 4px solid #667eea;
-            transition: all 0.3s;
-        }
-        
-        .sta-settings.disabled {
-            opacity: 0.4;
-            pointer-events: none;
-        }
-        
-        .sta-status {
-            margin-top: 15px;
-            padding: 12px 15px;
-            border-radius: 8px;
-            font-weight: 600;
-            display: flex;
-            align-items: center;
-            gap: 10px;
-        }
-        
-        .sta-status.connected {
-            background: linear-gradient(135deg, rgba(17, 153, 142, 0.1) 0%, rgba(56, 239, 125, 0.1) 100%);
-            border: 2px solid #11998e;
-            color: #0d6d62;
-        }
-        
-        .sta-status.disconnected {
-            background: linear-gradient(135deg, rgba(235, 51, 73, 0.1) 0%, rgba(244, 92, 67, 0.1) 100%);
-            border: 2px solid #eb3349;
-            color: #b8262f;
-        }
-        
-        .button-group {
-            display: flex;
-            gap: 12px;
-            margin-top: 25px;
-            flex-wrap: wrap;
-        }
-        
-        button {
-            flex: 1;
-            min-width: 180px;
-            padding: 14px 28px;
-            border: none;
-            border-radius: 8px;
-            font-size: 1em;
-            font-weight: 700;
-            cursor: pointer;
-            transition: all 0.3s;
-            text-transform: uppercase;
-            letter-spacing: 0.5px;
-        }
-        
-        .btn-save {
-            background: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
-            color: white;
-            box-shadow: 0 4px 15px rgba(17, 153, 142, 0.3);
-        }
-        
-        .btn-save:hover {
-            transform: translateY(-2px);
-            box-shadow: 0 6px 20px rgba(17, 153, 142, 0.4);
-        }
-        
-        .btn-cancel {
-            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
-            color: white;
-            box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
-        }
-        
-        .btn-cancel:hover {
-            transform: translateY(-2px);
-            box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
-        }
-        
-        .btn-reboot {
-            background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
-            color: white;
-            box-shadow: 0 4px 15px rgba(240, 147, 251, 0.3);
-        }
-        
-        .btn-reboot:hover {
-            transform: translateY(-2px);
-            box-shadow: 0 6px 20px rgba(240, 147, 251, 0.4);
-        }
-        
-        button:active {
-            transform: translateY(0);
-        }
-        
-        .alert {
-            padding: 15px 20px;
-            border-radius: 8px;
-            margin-bottom: 20px;
-            display: none;
-            align-items: center;
-            gap: 12px;
-            animation: slideDown 0.3s ease-out;
-            box-shadow: 0 3px 10px rgba(0,0,0,0.1);
-        }
-        
-        @keyframes slideDown {
-            from {
-                opacity: 0;
-                transform: translateY(-10px);
-            }
-            to {
-                opacity: 1;
-                transform: translateY(0);
-            }
-        }
-        
-        .alert.show {
-            display: flex;
-        }
-        
-        .alert-success {
-            background: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
-            color: white;
-        }
-        
-        .alert-info {
-            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
-            color: white;
-        }
-        
-        .alert-warning {
-            background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
-            color: white;
-        }
-        
-        .alert-icon {
-            font-size: 1.5em;
-        }
-        
-        .alert-text {
-            flex: 1;
-            font-weight: 600;
-        }
-        
-        .info-box {
-            background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
-            border-left: 4px solid #667eea;
-            padding: 18px 20px;
-            border-radius: 8px;
-            margin-top: 25px;
-        }
-        
-        .info-box-title {
-            font-weight: 700;
-            color: #333;
-            margin-bottom: 10px;
-            display: flex;
-            align-items: center;
-            gap: 8px;
-            font-size: 1.05em;
-        }
-        
-        .info-box-text {
-            color: #555;
-            font-size: 0.9em;
-            line-height: 1.7;
-        }
-        
-        .divider {
-            margin: 25px 0;
-            border: none;
-            border-top: 2px solid #e0e0e0;
-        }
-        
-        @media (max-width: 768px) {
-            .content { padding: 15px; }
-            .settings-section { padding: 18px; }
-            .section-title { font-size: 1.1em; }
-            button { min-width: 100%; }
-            .button-group { flex-direction: column; }
-        }
-    </style>
-</head>
-<body>
-    <div class="container">
-        <div class="header">
-            <h1>⚙️ System Settings</h1>
-            <p>Configure WiFi, Network, and System Parameters</p>
-        </div>
-        
-        <div class="nav">
-            <a href="/">📊 Monitor</a>
-            <a href="/transmit">📤 Transmit</a>
-            <a href="/graph">📈 Graph</a>
-            <a href="/graph-view">📊 Graph View</a>
-            <a href="/settings" class="active">⚙️ Settings</a>
-            <a href="/serial">📟 Serial</a>
-        </div>
-        
-        <div class="content">
-            <div id="alert-success" class="alert alert-success">
-                <span class="alert-icon">✓</span>
-                <span class="alert-text">Settings saved successfully! Reboot to apply.</span>
-            </div>
-            
-            <div id="alert-loading" class="alert alert-info">
-                <span class="alert-icon">⏳</span>
-                <span class="alert-text">Loading settings...</span>
-            </div>
-            
-            <div id="alert-warning" class="alert alert-warning">
-                <span class="alert-icon">⚠️</span>
-                <span class="alert-text">Warning message</span>
-            </div>
-            
-            <div class="settings-section">
-                <div class="section-title">
-                    <span>📶</span>
-                    <span>WiFi Configuration</span>
-                </div>
-                
-                <div class="subsection-title">
-                    <span>🔷</span>
-                    <span>AP Mode (Access Point)</span>
-                </div>
-                <p style="color: #666; font-size: 0.9em; margin-bottom: 15px;">
-                    ESP32가 생성하는 WiFi 네트워크 설정입니다. 기본적으로 항상 활성화됩니다.
-                </p>
-                
-                <div class="form-group">
-                    <label for="wifi-ssid">📡 AP SSID (Network Name)</label>
-                    <input type="text" id="wifi-ssid" placeholder="Byun_CAN_Logger" maxlength="31">
-                    <div class="help-text">WiFi 네트워크 이름 (1-31자)</div>
-                </div>
-                
-                <div class="form-group">
-                    <label for="wifi-password">🔒 AP Password</label>
-                    <input type="password" id="wifi-password" placeholder="Minimum 8 characters" minlength="8" maxlength="63">
-                    <div class="help-text">WiFi 비밀번호 (8-63자, 비워두면 개방 네트워크)</div>
-                </div>
-                
-                <hr class="divider">
-                
-                <div class="subsection-title">
-                    <span>🔶</span>
-                    <span>APSTA Mode (AP + Station)</span>
-                </div>
-                <p style="color: #666; font-size: 0.9em; margin-bottom: 15px;">
-                    외부 WiFi 공유기에 연결하여 인터넷 접속 및 NTP 시간 동기화를 사용할 수 있습니다.
-                </p>
-                
-                <div class="checkbox-group">
-                    <input type="checkbox" id="sta-enable" onchange="toggleSTASettings()">
-                    <label for="sta-enable">
-                        <strong>Enable Station Mode</strong> - Connect to external WiFi network
-                    </label>
-                </div>
-                
-                <div id="sta-settings" class="sta-settings disabled">
-                    <div class="form-group">
-                        <label for="sta-ssid">📡 WiFi SSID to Connect</label>
-                        <input type="text" id="sta-ssid" placeholder="Your router's WiFi name" maxlength="31">
-                        <div class="help-text">연결할 공유기의 WiFi 이름</div>
-                    </div>
-                    
-                    <div class="form-group">
-                        <label for="sta-password">🔒 WiFi Password</label>
-                        <input type="password" id="sta-password" placeholder="Router password" maxlength="63">
-                        <div class="help-text">공유기의 WiFi 비밀번호</div>
-                    </div>
-                    
-                    <div id="sta-status" class="sta-status disconnected" style="display: none;">
-                        <span id="sta-status-icon">✗</span>
-                        <div>
-                            <div id="sta-status-text">Not connected</div>
-                            <div id="sta-ip" style="font-size: 0.85em; opacity: 0.8; margin-top: 3px;"></div>
-                        </div>
-                    </div>
-                </div>
-            </div>
-            
-            <div class="button-group">
-                <button class="btn-save" onclick="saveSettings()">💾 Save Settings</button>
-                <button class="btn-reboot" onclick="rebootDevice()">🔄 Reboot Device</button>
-                <button class="btn-cancel" onclick="location.href='/'">← Back</button>
-            </div>
-            
-            <div class="info-box">
-                <div class="info-box-title">
-                    <span>💡</span>
-                    <span>Important Information</span>
-                </div>
-                <div class="info-box-text">
-                    <strong>WiFi 설정 변경 시:</strong><br>
-                    • 설정 저장 후 <strong>"Reboot Device"</strong> 버튼을 눌러 재부팅해야 적용됩니다.<br>
-                    • 재부팅 시 기존 AP 연결이 끊어지므로, 새로운 SSID로 다시 접속하세요.<br><br>
-                    
-                    <strong>APSTA 모드:</strong><br>
-                    • Station 모드 활성화 시 ESP32가 AP와 Station을 동시에 사용합니다.<br>
-                    • 외부 WiFi에 연결하면 NTP를 통한 자동 시간 동기화가 가능합니다.<br>
-                    • Station 연결 실패 시에도 AP 모드는 정상 동작합니다.<br><br>
-                    
-                    <strong>현재 접속 정보:</strong><br>
-                    • AP IP: <strong>192.168.4.1</strong> (기본값)<br>
-                    • WebSocket Port: <strong>81</strong><br>
-                    • HTTP Port: <strong>80</strong>
-                </div>
-            </div>
-        </div>
-    </div>
-    
-    <script>
-        let ws;
-        
-        function initWebSocket() {
-            ws = new WebSocket('ws://' + window.location.hostname + ':81/');
-            
-            ws.onopen = function() {
-                console.log('✓ WebSocket connected');
-                loadSettings();
-            };
-            
-            ws.onclose = function() {
-                console.log('✗ WebSocket disconnected');
-                showAlert('alert-warning', '⚠️ Connection lost. Reconnecting...', 'alert-warning');
-                setTimeout(initWebSocket, 3000);
-            };
-            
-            ws.onerror = function(error) {
-                console.error('WebSocket error:', error);
-            };
-            
-            ws.onmessage = function(event) {
-                try {
-                    const data = JSON.parse(event.data);
-                    
-                    if (data.type === 'settings') {
-                        handleSettingsResponse(data);
-                    } else if (data.type === 'settingsSaved') {
-                        if (data.success) {
-                            showAlert('alert-success', '✓ Settings saved! Reboot to apply changes.', 'alert-success');
-                        } else {
-                            showAlert('alert-warning', '✗ Failed to save settings', 'alert-warning');
-                        }
-                    }
-                } catch (e) {
-                    console.error('Parse error:', e);
-                }
-            };
-        }
-        
-        function handleSettingsResponse(data) {
-            document.getElementById('wifi-ssid').value = data.ssid || 'Byun_CAN_Logger';
-            document.getElementById('wifi-password').value = data.password || '';
-            
-            document.getElementById('sta-enable').checked = data.staEnable || false;
-            document.getElementById('sta-ssid').value = data.staSSID || '';
-            document.getElementById('sta-password').value = data.staPassword || '';
-            
-            toggleSTASettings();
-            
-            const staStatus = document.getElementById('sta-status');
-            const staStatusIcon = document.getElementById('sta-status-icon');
-            const staStatusText = document.getElementById('sta-status-text');
-            const staIpElement = document.getElementById('sta-ip');
-            
-            if (data.staConnected && data.staIP && data.staIP !== '0.0.0.0') {
-                staStatus.className = 'sta-status connected';
-                staStatus.style.display = 'flex';
-                staStatusIcon.textContent = '✓';
-                staStatusText.textContent = 'Connected to WiFi';
-                staIpElement.textContent = 'IP Address: ' + data.staIP;
-            } else if (data.staEnable) {
-                staStatus.className = 'sta-status disconnected';
-                staStatus.style.display = 'flex';
-                staStatusIcon.textContent = '✗';
-                staStatusText.textContent = 'Not connected (Station mode enabled)';
-                staIpElement.textContent = 'Check WiFi credentials';
-            } else {
-                staStatus.style.display = 'none';
-            }
-            
-            hideAlert('alert-loading');
-            console.log('✓ Settings loaded:', data);
-        }
-        
-        function loadSettings() {
-            if (ws && ws.readyState === WebSocket.OPEN) {
-                ws.send(JSON.stringify({cmd: 'getSettings'}));
-                showAlert('alert-loading', '⏳ Loading settings...', 'alert-info');
-            }
-        }
-        
-        function saveSettings() {
-            const ssid = document.getElementById('wifi-ssid').value.trim();
-            const password = document.getElementById('wifi-password').value;
-            const staEnable = document.getElementById('sta-enable').checked;
-            const staSSID = document.getElementById('sta-ssid').value.trim();
-            const staPassword = document.getElementById('sta-password').value;
-            
-            // 입력 검증
-            if (ssid.length === 0) {
-                alert('⚠️ Please enter AP SSID');
-                return;
-            }
-            
-            if (ssid.length > 31) {
-                alert('⚠️ AP SSID maximum length is 31 characters');
-                return;
-            }
-            
-            if (password.length > 0 && password.length < 8) {
-                alert('⚠️ AP Password must be at least 8 characters (or leave empty for open network)');
-                return;
-            }
-            
-            if (password.length > 63) {
-                alert('⚠️ AP Password maximum length is 63 characters');
-                return;
-            }
-            
-            if (staEnable) {
-                if (staSSID.length === 0) {
-                    alert('⚠️ Please enter Station WiFi SSID or disable Station mode');
-                    return;
-                }
-                if (staSSID.length > 31) {
-                    alert('⚠️ Station SSID maximum length is 31 characters');
-                    return;
-                }
-            }
-            
-            const settings = {
-                cmd: 'saveSettings',
-                ssid: ssid,
-                password: password,
-                staEnable: staEnable,
-                staSSID: staSSID,
-                staPassword: staPassword
-            };
-            
-            if (ws && ws.readyState === WebSocket.OPEN) {
-                ws.send(JSON.stringify(settings));
-                console.log('✓ Saving settings:', settings);
-            } else {
-                alert('⚠️ WebSocket disconnected. Please refresh the page.');
-            }
-        }
-        
-        function rebootDevice() {
-            if (!confirm('⚠️ Reboot the device?\n\nCurrent connections will be lost.\nAfter reboot, reconnect to WiFi (use new SSID if changed).')) {
-                return;
-            }
-            
-            if (ws && ws.readyState === WebSocket.OPEN) {
-                ws.send(JSON.stringify({cmd: 'reboot'}));
-                
-                showAlert('alert-info', '🔄 Rebooting device... Please wait 10 seconds.', 'alert-info');
-                
-                setTimeout(() => {
-                    alert('Reboot complete!\n\nIf SSID was changed, reconnect to the new network.\nThen access: http://192.168.4.1');
-                }, 3000);
-            }
-        }
-        
-        function showAlert(alertId, message, className) {
-            // 모든 알림 숨김
-            document.querySelectorAll('.alert').forEach(alert => {
-                alert.classList.remove('show');
-            });
-            
-            const alert = document.getElementById(alertId);
-            if (alert) {
-                const textElement = alert.querySelector('.alert-text');
-                if (textElement && message) {
-                    textElement.textContent = message;
-                }
-                
-                alert.className = 'alert ' + className;
-                alert.classList.add('show');
-                
-                if (className === 'alert-success') {
-                    setTimeout(() => {
-                        hideAlert(alertId);
-                    }, 5000);
-                }
-            }
-        }
-        
-        function hideAlert(alertId) {
-            const alert = document.getElementById(alertId);
-            if (alert) {
-                alert.classList.remove('show');
-            }
-        }
-        
-        function toggleSTASettings() {
-            const staEnable = document.getElementById('sta-enable').checked;
-            const staSettings = document.getElementById('sta-settings');
-            
-            if (staEnable) {
-                staSettings.classList.remove('disabled');
-            } else {
-                staSettings.classList.add('disabled');
-            }
-        }
-        
-        window.addEventListener('load', function() {
-            initWebSocket();
-        });
-    </script>
-</body>
-</html>
-)rawliteral";
-
-#endif
