script.js

import { initializeApp } from "https://www.gstatic.com/firebasejs/10.8.1/firebase-app.js";
import { getAnalytics } from "https://www.gstatic.com/firebasejs/10.8.1/firebase-analytics.js";
import { getAuth, createUserWithEmailAndPassword, signInWithEmailAndPassword, onAuthStateChanged, signOut, GoogleAuthProvider, signInWithPopup, sendPasswordResetEmail } from "https://www.gstatic.com/firebasejs/10.8.1/firebase-auth.js";

const firebaseConfig = {
  apiKey: "AIzaSyDhgX9WcAEQ_kgGiFFpxWVaDSDPo7-gDIQ",
  authDomain: "iq-test-web-ff0cd.firebaseapp.com",
  projectId: "iq-test-web-ff0cd",
  storageBucket: "iq-test-web-ff0cd.firebasestorage.app",
  messagingSenderId: "814260349055",
  appId: "1:814260349055:web:de102a540551aa7950b74a",
  measurementId: "G-5N03TMBFRD"
};

const app = initializeApp(firebaseConfig);
const analytics = getAnalytics(app);
const auth = getAuth(app);

// --- 1. Audio & Haptic Engine ---
const AudioContext = window.AudioContext || window.webkitAudioContext;
let audioCtx;

const SoundEngine = {
    init: function() {
        if (!audioCtx) audioCtx = new AudioContext();
        if (audioCtx.state === 'suspended') audioCtx.resume();
    },
    playTone: function(freq, type, duration, vol=0.1) {
        if (!audioCtx) return;
        const osc = audioCtx.createOscillator();
        const gain = audioCtx.createGain();
        osc.type = type;
        osc.frequency.setValueAtTime(freq, audioCtx.currentTime);
        gain.gain.setValueAtTime(vol, audioCtx.currentTime);
        gain.gain.exponentialRampToValueAtTime(0.01, audioCtx.currentTime + duration);
        osc.connect(gain);
        gain.connect(audioCtx.destination);
        osc.start();
        osc.stop(audioCtx.currentTime + duration);
    },
    pop: function() { this.playTone(400, 'sine', 0.1, 0.15); },
    chime: function() { 
        this.playTone(800, 'triangle', 0.3, 0.1); 
        setTimeout(() => this.playTone(1200, 'triangle', 0.4, 0.1), 100);
    },
    buzz: function() { this.playTone(150, 'sawtooth', 0.3, 0.2); },
    victory: function() {
        [523.25, 659.25, 783.99, 1046.50].forEach((freq, i) => { // C Major Arpeggio
            setTimeout(() => this.playTone(freq, 'sine', 0.4, 0.15), i * 150);
        });
    },
    vibrate: function(pattern) {
        if (navigator.vibrate) navigator.vibrate(pattern);
    }
};

// --- 2. Localization Dictionary ---
const uiTranslations = {
    en: {
        welcomeBack: "Welcome Back", loginToContinue: "Log in to continue your IQ journey",
        loginBtn: "Log In", or: "OR", continueGoogle: "Continue with Google",
        noAccount: "Don't have an account?", signUpLink: "Sign up", acceptBtn: "Accept & Continue",
        endTest: "End Test", logout: "Logout", yourHighScore: "Your High Score:",
        chooseChallenge: "Choose your challenge level and the number of questions.",
        difficulty: "Difficulty Level:", beginner: "Beginner", intermediate: "Intermediate", advanced: "Advanced",
        category: "Category:", allCategories: "All Categories", numQuestions: "Number of Questions:",
        gameMode: "Game Mode:", modeStandard: "Standard (20s / question)", modeZen: "Zen (No timer)", modeSprint: "Sprint (5 min, unlimited)",
        startTest: "Start Test", testComplete: "Test Complete!",
        simulatedScore: "Your Simulated IQ Score", restartTest: "Restart Test",
        wait: "Please wait...", createAccount: "Create Account", signupText: "Sign up to start tracking your IQ scores",
        alreadyAccount: "Already have an account?", loginLink: "Log in",
        adaptive: "Adaptive", reviewAnswers: "Review Incorrect Answers",
        cat_math: "Math", cat_logic: "Logic", cat_general: "General", cat_science: "Science", cat_history: "History", cat_geography: "Geography", cat_arts: "Arts", cat_sociology: "Sociology", cat_philosophy: "Philosophy", cat_economics: "Economics",
        alert_pwdMatch: "Passwords do not match.", alert_regSuccess: "Registration successful!", alert_enterEmail: "Please enter your email address first to reset your password.", alert_resetSent: "Password reset email sent! Check your inbox.", alert_logoutSuccess: "Thank you for using IQ Master! You have been successfully logged out.", alert_acceptTnc: "You must accept the Terms & Conditions to use IQ Master.",
        confirm_langChange: "Language changed. Do you want to restart the test to apply the new language to the questions?", confirm_endTest: "Are you sure you want to end the test? Your progress will be lost.",
        feedback_perfect: "Perfect! You're a logical genius!", feedback_great: "Great job! You have very strong cognitive skills.", feedback_good: "Good effort, but there's room for improvement.", feedback_keepPracticing: "Keep practicing! Logic puzzles take time and repetition.",
        score_earned: "You earned <strong>{0}</strong> points out of a possible {1} ({2}%).", score_simulated: "*This is a simulated score for entertainment purposes.", ans_timeout: "No answer (Timeout)", exp_default: "The correct logical deduction leads to {0}. Review this specific concept to improve your accuracy in future tests.", prog_points: "Points: ", prog_question: "Question {0} of {1}", q_label: "Q:", your_ans: "Your Answer:", correct_ans: "Correct Answer:"
    },
    es: {
        welcomeBack: "Bienvenido", loginToContinue: "Inicia sesión para continuar",
        loginBtn: "Iniciar sesión", or: "O", continueGoogle: "Continuar con Google",
        noAccount: "¿No tienes cuenta?", signUpLink: "Regístrate", acceptBtn: "Aceptar y continuar",
        endTest: "Terminar prueba", logout: "Cerrar sesión", yourHighScore: "Tu puntuación más alta:",
        chooseChallenge: "Elige tu nivel de desafío y el número de preguntas.",
        difficulty: "Nivel de dificultad:", beginner: "Principiante", intermediate: "Intermedio", advanced: "Avanzado",
        category: "Categoría:", allCategories: "Todas las categorías", numQuestions: "Número de preguntas:",
        gameMode: "Modo de juego:", modeStandard: "Estándar", modeZen: "Modo Zen", modeSprint: "Sprint (5 min)",
        startTest: "Empezar prueba", testComplete: "¡Prueba completada!",
        simulatedScore: "Tu coeficiente intelectual simulado", restartTest: "Reiniciar prueba",
        wait: "Por favor espera...", createAccount: "Crear cuenta", signupText: "Regístrate para rastrear tus puntajes",
        alreadyAccount: "¿Ya tienes cuenta?", loginLink: "Inicia sesión",
        adaptive: "Adaptativo", reviewAnswers: "Revisar respuestas incorrectas",
        cat_math: "Matemáticas", cat_logic: "Lógica", cat_general: "General", cat_science: "Ciencia", cat_history: "Historia", cat_geography: "Geografía", cat_arts: "Artes", cat_sociology: "Sociología", cat_philosophy: "Filosofía", cat_economics: "Economía",
        alert_pwdMatch: "Las contraseñas no coinciden.", alert_regSuccess: "¡Registro exitoso!", alert_enterEmail: "Ingrese su correo electrónico para restablecer su contraseña.", alert_resetSent: "¡Correo de restablecimiento enviado! Revise su bandeja de entrada.", alert_logoutSuccess: "¡Gracias por usar IQ Master! Has cerrado sesión exitosamente.", alert_acceptTnc: "Debes aceptar los Términos y Condiciones para usar IQ Master.",
        confirm_langChange: "Idioma cambiado. ¿Deseas reiniciar la prueba para aplicar el nuevo idioma a las preguntas?", confirm_endTest: "¿Estás seguro de que quieres terminar la prueba? Perderás tu progreso.",
        feedback_perfect: "¡Perfecto! ¡Eres un genio lógico!", feedback_great: "¡Gran trabajo! Tienes habilidades cognitivas muy fuertes.", feedback_good: "Buen esfuerzo, pero hay margen de mejora.", feedback_keepPracticing: "¡Sigue practicando! Los acertijos lógicos requieren tiempo.",
        score_earned: "Ganaste <strong>{0}</strong> puntos de {1} posibles ({2}%).", score_simulated: "*Esta es una puntuación simulada con fines de entretenimiento.", ans_timeout: "Sin respuesta (Tiempo agotado)", exp_default: "La deducción lógica correcta lleva a {0}. Revisa este concepto para mejorar en futuras pruebas.", prog_points: "Puntos: ", prog_question: "Pregunta {0} de {1}", q_label: "P:", your_ans: "Tu respuesta:", correct_ans: "Respuesta correcta:"
    },
    fr: {
        welcomeBack: "Bon retour", loginToContinue: "Connectez-vous pour continuer",
        loginBtn: "Connexion", or: "OU", continueGoogle: "Continuer avec Google",
        noAccount: "Pas de compte ?", signUpLink: "S'inscrire", acceptBtn: "Accepter et continuer",
        endTest: "Terminer le test", logout: "Déconnexion", yourHighScore: "Votre meilleur score :",
        chooseChallenge: "Choisissez votre niveau et le nombre de questions.",
        difficulty: "Niveau de difficulté :", beginner: "Débutant", intermediate: "Intermédiaire", advanced: "Avancé",
        category: "Catégorie :", allCategories: "Toutes les catégories", numQuestions: "Nombre de questions :",
        gameMode: "Mode de jeu :", modeStandard: "Standard", modeZen: "Zen", modeSprint: "Sprint (5 min)",
        startTest: "Commencer le test", testComplete: "Test terminé !",
        simulatedScore: "Votre QI simulé", restartTest: "Recommencer",
        wait: "Veuillez patienter...", createAccount: "Créer un compte", signupText: "Inscrivez-vous pour suivre vos scores",
        alreadyAccount: "Déjà un compte ?", loginLink: "Connexion",
        adaptive: "Adaptatif", reviewAnswers: "Revoir les mauvaises réponses",
        cat_math: "Mathématiques", cat_logic: "Logique", cat_general: "Général", cat_science: "Science", cat_history: "Histoire", cat_geography: "Géographie", cat_arts: "Arts", cat_sociology: "Sociologie", cat_philosophy: "Philosophie", cat_economics: "Économie",
        alert_pwdMatch: "Les mots de passe ne correspondent pas.", alert_regSuccess: "Inscription réussie !", alert_enterEmail: "Veuillez entrer votre e-mail pour réinitialiser votre mot de passe.", alert_resetSent: "E-mail de réinitialisation envoyé ! Vérifiez votre boîte de réception.", alert_logoutSuccess: "Merci d'utiliser IQ Master ! Vous avez été déconnecté avec succès.", alert_acceptTnc: "Vous devez accepter les conditions générales pour utiliser IQ Master.",
        confirm_langChange: "Langue modifiée. Voulez-vous recommencer le test pour appliquer la nouvelle langue aux questions ?", confirm_endTest: "Êtes-vous sûr de vouloir terminer le test ? Votre progression sera perdue.",
        feedback_perfect: "Parfait ! Vous êtes un génie de la logique !", feedback_great: "Bon travail ! Vous avez de très fortes compétences cognitives.", feedback_good: "Bel effort, mais il y a place à l'amélioration.", feedback_keepPracticing: "Continuez à vous entraîner ! Les énigmes logiques demandent du temps.",
        score_earned: "Vous avez obtenu <strong>{0}</strong> points sur un possible de {1} ({2}%).", score_simulated: "*Il s'agit d'un score simulé à des fins de divertissement.", ans_timeout: "Pas de réponse (Délai écoulé)", exp_default: "La déduction logique correcte mène à {0}. Révisez ce concept pour améliorer votre précision.", prog_points: "Points : ", prog_question: "Question {0} sur {1}", q_label: "Q :", your_ans: "Votre réponse :", correct_ans: "Bonne réponse :"
    },
    hi: {
        welcomeBack: "वापसी पर स्वागत है", loginToContinue: "जारी रखने के लिए लॉगिन करें",
        loginBtn: "लॉग इन करें", or: "या", continueGoogle: "Google के साथ जारी रखें",
        noAccount: "खाता नहीं है?", signUpLink: "साइन अप करें", acceptBtn: "स्वीकार करें",
        endTest: "टेस्ट समाप्त करें", logout: "लॉग आउट", yourHighScore: "आपका उच्चतम स्कोर:",
        chooseChallenge: "अपना चुनौती स्तर और प्रश्नों की संख्या चुनें।",
        difficulty: "कठिनाई स्तर:", beginner: "शुरुआती", intermediate: "माध्यमिक", advanced: "उन्नत",
        category: "श्रेणी:", allCategories: "सभी श्रेणियाँ", numQuestions: "प्रश्नों की संख्या:",
        gameMode: "गेम मोड:", modeStandard: "मानक", modeZen: "ज़ेन", modeSprint: "स्प्रिंट (5 मिनट)",
        startTest: "टेस्ट शुरू करें", testComplete: "टेस्ट पूरा हुआ!",
        simulatedScore: "आपका अनुमानित IQ", restartTest: "फिर से शुरू करें",
        wait: "कृपया प्रतीक्षा करें...", createAccount: "खाता बनाएं", signupText: "स्कोर ट्रैक करने के लिए साइन अप करें",
        alreadyAccount: "क्या आपके पास पहले से खाता है?", loginLink: "लॉग इन करें",
        adaptive: "अनुकूली", reviewAnswers: "गलत उत्तरों की समीक्षा करें",
        cat_math: "गणित", cat_logic: "तर्क", cat_general: "सामान्य", cat_science: "विज्ञान", cat_history: "इतिहास", cat_geography: "भूगोल", cat_arts: "कला", cat_sociology: "समाजशास्त्र", cat_philosophy: "दर्शनशास्त्र", cat_economics: "अर्थशास्त्र",
        alert_pwdMatch: "पासवर्ड मेल नहीं खाते।", alert_regSuccess: "पंजीकरण सफल!", alert_enterEmail: "पासवर्ड रीसेट करने के लिए कृपया पहले अपना ईमेल पता दर्ज करें।", alert_resetSent: "पासवर्ड रीसेट ईमेल भेज दिया गया! अपना इनबॉक्स जांचें।", alert_logoutSuccess: "IQ Master का उपयोग करने के लिए धन्यवाद! आप सफलतापूर्वक लॉग आउट हो गए हैं।", alert_acceptTnc: "IQ Master का उपयोग करने के लिए आपको नियम और शर्तें स्वीकार करनी होंगी।",
        confirm_langChange: "भाषा बदल गई। क्या आप प्रश्नों पर नई भाषा लागू करने के लिए परीक्षण को फिर से शुरू करना चाहते हैं?", confirm_endTest: "क्या आप वाकई परीक्षण समाप्त करना चाहते हैं? आपकी प्रगति नष्ट हो जाएगी।",
        feedback_perfect: "बिल्कुल सही! आप एक तार्किक प्रतिभाशाली हैं!", feedback_great: "बहुत बढ़िया! आपके पास बहुत मजबूत संज्ञानात्मक कौशल हैं।", feedback_good: "अच्छा प्रयास, लेकिन सुधार की गुंजाइश है।", feedback_keepPracticing: "अभ्यास करते रहें! तर्क पहेली में समय और दोहराव लगता है।",
        score_earned: "आपने संभावित {1} में से <strong>{0}</strong> अंक अर्जित किए ({2}%)।", score_simulated: "*यह मनोरंजन के उद्देश्य से एक सिम्युलेटेड स्कोर है।", ans_timeout: "कोई उत्तर नहीं (समय समाप्त)", exp_default: "सही तार्किक निष्कर्ष {0} की ओर ले जाता है। भविष्य में अपनी सटीकता में सुधार के लिए इसकी समीक्षा करें।", prog_points: "अंक: ", prog_question: "प्रश्न {0} / {1}", q_label: "प्रश्न:", your_ans: "आपका उत्तर:", correct_ans: "सही उत्तर:"
    },
    mr: {
        welcomeBack: "पुन्हा स्वागत आहे", loginToContinue: "सुरू ठेवण्यासाठी लॉग इन करा",
        loginBtn: "लॉग इन करा", or: "किंवा", continueGoogle: "Google सह सुरू ठेवा",
        noAccount: "खाते नाही?", signUpLink: "साइन अप करा", acceptBtn: "स्वीकारा आणि पुढे जा",
        endTest: "चाचणी समाप्त करा", logout: "लॉग आउट", yourHighScore: "तुमचा सर्वोच्च स्कोअर:",
        chooseChallenge: "तुमची आव्हान पातळी आणि प्रश्नांची संख्या निवडा.",
        difficulty: "कठिण पातळी:", beginner: "नवशिक्या", intermediate: "मध्यम", advanced: "प्रगत",
        category: "श्रेणी:", allCategories: "सर्व श्रेणी", numQuestions: "प्रश्नांची संख्या:",
        gameMode: "गेम मोड:", modeStandard: "प्रमाणित", modeZen: "झेन", modeSprint: "स्प्रिंट (५ मि)",
        startTest: "चाचणी सुरू करा", testComplete: "चाचणी पूर्ण झाली!",
        simulatedScore: "तुमचा अंदाजित IQ", restartTest: "पुन्हा सुरू करा",
        wait: "कृपया प्रतीक्षा करा...", createAccount: "खाते तयार करा", signupText: "स्कोअर ट्रॅक करण्यासाठी साइन अप करा",
        alreadyAccount: "तुमचे आधीच खाते आहे का?", loginLink: "लॉग इन करा",
        adaptive: "अनुकूली", reviewAnswers: "चुकीच्या उत्तरांचे पुनरावलोकन करा",
        cat_math: "गणित", cat_logic: "तर्क", cat_general: "सामान्य", cat_science: "विज्ञान", cat_history: "इतिहास", cat_geography: "भूगोल", cat_arts: "कला", cat_sociology: "समाजशास्त्र", cat_philosophy: "तत्त्वज्ञान", cat_economics: "अर्थशास्त्र",
        alert_pwdMatch: "पासवर्ड जुळत नाहीत.", alert_regSuccess: "नोंदणी यशस्वी!", alert_enterEmail: "पासवर्ड रीसेट करण्यासाठी कृपया प्रथम तुमचा ईमेल पत्ता प्रविष्ट करा.", alert_resetSent: "पासवर्ड रीसेट ईमेल पाठवला! तुमचा इनबॉक्स तपासा.", alert_logoutSuccess: "IQ Master वापरल्याबद्दल धन्यवाद! तुम्ही यशस्वीरित्या लॉग आउट झाला आहात.", alert_acceptTnc: "IQ Master वापरण्यासाठी तुम्हाला नियम आणि अटी स्वीकारणे आवश्यक आहे.",
        confirm_langChange: "भाषा बदलली. प्रश्नांवर नवीन भाषा लागू करण्यासाठी तुम्हाला चाचणी पुन्हा सुरू करायची आहे का?", confirm_endTest: "तुम्हाला नक्की चाचणी संपवायची आहे का? तुमची प्रगती नष्ट होईल.",
        feedback_perfect: "परिपूर्ण! तुम्ही एक तार्किक نابغه आहात!", feedback_great: "उत्तम काम! तुमच्याकडे खूप मजबूत संज्ञानात्मक कौशल्ये आहेत.", feedback_good: "चांगला प्रयत्न, पण सुधारणेला वाव आहे.", feedback_keepPracticing: "सराव करत राहा! तर्क कोडी सोडवण्यासाठी वेळ आणि पुनरावृत्ती लागते.",
        score_earned: "तुम्ही शक्य असलेल्या {1} पैकी <strong>{0}</strong> गुण मिळवले ({2}%).", score_simulated: "*हे मनोरंजनाच्या उद्देशाने एक सिम्युलेटेड स्कोअर आहे.", ans_timeout: "उत्तर नाही (वेळ संपली)", exp_default: "योग्य तार्किक निष्कर्ष {0} कडे नेतो. भविष्यातील चाचण्यांमध्ये तुमची अचूकता सुधारण्यासाठी या संकल्पनेचे पुनरावलोकन करा.", prog_points: "गुण: ", prog_question: "प्रश्न {0} / {1}", q_label: "प्र:", your_ans: "तुमचे उत्तर:", correct_ans: "बरोबर उत्तर:"
    }
};

let baseQuestionBank = {};
let questionBank = {};

// 4. State Variables
let currentLang = 'en';
let currentIndex = 0;
let currentTestQuestions = [];
let answerLog = []; // To store { question, correct: true/false }
let questionTimerInterval = null; // To hold the timer's interval ID

// Sprint & Adaptive Mechanics Variables
let gameMode = 'standard';
let globalTimeLeft = 300; // 5 minutes
let globalTimerInterval = null;
let isAdaptive = false;
let adaptiveStreak = 0;
let currentDifficulty = 'beginner';
let weightedScore = 0;
let maxPossibleScore = 0;
let questionPools = { beginner: [], intermediate: [], advanced: [] };
let targetQuestionCount = 10;

// --- True Randomization Shuffle (Fisher-Yates) ---
function shuffleArray(array) {
    let curId = array.length;
    while (0 !== curId) {
        let randId = Math.floor(Math.random() * curId);
        curId -= 1;
        let tmp = array[curId];
        array[curId] = array[randId];
        array[randId] = tmp;
    }
    return array;
}

// Constants
const TIME_PER_QUESTION = 20; // Seconds
const SPRINT_TIME = 300; // 5 minutes
const HIGH_SCORE_KEY = 'iqQuizHighScore';
const THEME_KEY = 'iqQuizTheme';

// 3. DOM Elements
const questionTextElement = document.getElementById("question-text");
const questionImageElement = document.getElementById("question-image");
const optionsContainer = document.getElementById("options-container");
const progressText = document.getElementById("progress-text");
const progressFill = document.getElementById("progress-fill");
const quizHeaderInfo = document.getElementById("quiz-header-info");
const configArea = document.getElementById("config-area");
const startBtn = document.getElementById("start-btn");
const quizArea = document.getElementById("quiz-area");
const resultArea = document.getElementById("result-area");
const scoreText = document.getElementById("score-text");
const restartBtn = document.getElementById("restart-btn");
const terminateBtn = document.getElementById("terminate-btn");
const iqScoreValue = document.getElementById("iq-score-value");
const resultsGraphContainer = document.getElementById("results-graph-container");
const explanationsContainer = document.getElementById("explanations-container");
const explanationsList = document.getElementById("explanations-list");
const timerText = document.getElementById("timer-text");
const timerContainer = document.getElementById("timer-container");
const highScoreDisplay = document.getElementById("high-score-display");
const questionCountSelect = document.getElementById('question-count');
const categorySelection = document.getElementById('category-selection');
const gameModeSelect = document.getElementById('game-mode');
const themeToggle = document.getElementById('theme-toggle');
const languageSelect = document.getElementById('language-select');
const authContainer = document.getElementById('auth-container');
const tncContainer = document.getElementById('tnc-container');
const tncCheckbox = document.getElementById('tnc-checkbox');
const tncAcceptBtn = document.getElementById('tnc-accept-btn');
const tncDeclineBtn = document.getElementById('tnc-decline-btn');
const mainAppContainer = document.getElementById('main-app-container');
const authForm = document.getElementById('auth-form');
const authEmail = document.getElementById('auth-email');
const authPassword = document.getElementById('auth-password');
const authConfirmPassword = document.getElementById('auth-confirm-password');
const confirmPasswordGroup = document.getElementById('confirm-password-group');
const authSubmitBtn = document.getElementById('auth-submit-btn');
const forgotPasswordContainer = document.getElementById('forgot-password-container');
const forgotPasswordLink = document.getElementById('forgot-password-link');
const userInfoDisplay = document.getElementById('user-info-display');
const authSwitchLink = document.getElementById('auth-switch-link');
const authSwitchText = document.getElementById('auth-switch-text');
const authTitle = document.getElementById('auth-title');
const authSubtitle = document.getElementById('auth-subtitle');
const googleLoginBtn = document.getElementById('google-login-btn');
const authMessage = document.getElementById('auth-message');
const logoutBtn = document.getElementById('logout-btn');
const body = document.body;

// 5. Core Functions
function generateAndStartQuiz() {
    SoundEngine.init();
    
    const level = document.querySelector('input[name="level"]:checked').value;
    const selectedCategory = categorySelection.value;
    gameMode = gameModeSelect.value;
    targetQuestionCount = gameMode === 'sprint' ? Infinity : parseInt(questionCountSelect.value);

    // Reset Adaptive pools & mechanics
    questionPools = { beginner: [], intermediate: [], advanced: [] };
    isAdaptive = level === 'adaptive';
    adaptiveStreak = 0;
    currentDifficulty = isAdaptive ? 'intermediate' : level; // Start adaptive in the middle
    
    // Populate the drawing pools
    if (isAdaptive) {
        ['beginner', 'intermediate', 'advanced'].forEach(diff => fillPool(diff, selectedCategory));
    } else {
        fillPool(level, selectedCategory);
    }

    weightedScore = 0;
    maxPossibleScore = 0;
    currentIndex = 0;
    currentTestQuestions = [];
    answerLog = [];

    // Hide config screen, show quiz elements
    configArea.classList.add("hidden");
    quizArea.classList.remove("hidden");
    quizHeaderInfo.classList.remove("hidden");
    terminateBtn.classList.remove("hidden");

    clearInterval(globalTimerInterval);
    if (gameMode === 'sprint') {
        timerContainer.classList.remove('hidden');
        startSprintTimer();
    } else if (gameMode === 'zen') {
        timerContainer.classList.add('hidden');
    } else {
        timerContainer.classList.remove('hidden');
    }
    
    loadQuestion();
}

function fillPool(diff, cat) {
    let langObj = questionBank[currentLang] || questionBank['en'];
    let langLevel = langObj[diff] || {};
    let enLevel = questionBank['en'][diff] || {};
    
    let available = [];
    
    if (cat === 'all') {
        const allCats = new Set([...Object.keys(langLevel), ...Object.keys(enLevel)]);
        allCats.forEach(c => {
            if (langLevel[c] && langLevel[c].length > 0) available.push(...langLevel[c]);
            else if (enLevel[c]) available.push(...enLevel[c]);
        });
    } else {
        if (langLevel[cat] && langLevel[cat].length > 0) available.push(...langLevel[cat]);
        else if (enLevel[cat]) available.push(...enLevel[cat]);
    }
    
    // Map them with a difficulty property for weighted scoring and properly shuffle
    // We also make a deep copy so we don't accidentally mutate the bank
    let mappedQuestions = available.map(q => ({ ...q, difficulty: diff, o: [...q.o] }));
    questionPools[diff] = shuffleArray(mappedQuestions);
}

function getNextQuestion() {
    let pool = questionPools[currentDifficulty];
    if (pool.length === 0) {
        // If empty, downgrade or upgrade
        if (questionPools['intermediate'].length > 0) currentDifficulty = 'intermediate';
        else if (questionPools['advanced'].length > 0) currentDifficulty = 'advanced';
        else if (questionPools['beginner'].length > 0) currentDifficulty = 'beginner';
        else return null; // Complete exhaustion
        pool = questionPools[currentDifficulty];
    }
    return pool.pop(); // Take last since it's already shuffled
}

function getWeight(diff) {
    if (diff === 'advanced') return 3;
    if (diff === 'intermediate') return 2;
    return 1;
}

function formatTime(seconds) {
    if (gameMode !== 'sprint') return seconds;
    const m = Math.floor(seconds / 60);
    const s = seconds % 60;
    return `${m}:${s < 10 ? '0' : ''}${s}`;
}

function startSprintTimer() {
    globalTimeLeft = SPRINT_TIME;
    timerText.textContent = formatTime(globalTimeLeft);
    timerText.style.color = 'var(--text-secondary)';
    timerContainer.classList.remove('timer-low');

    globalTimerInterval = setInterval(() => {
        globalTimeLeft--;
        timerText.textContent = formatTime(globalTimeLeft);
        
        if (globalTimeLeft <= 15) {
            timerText.style.color = 'var(--error-color)';
            timerContainer.classList.add('timer-low');
        }
        if (globalTimeLeft <= 0) {
            clearInterval(globalTimerInterval);
            showResults();
        }
    }, 1000);
}

function startTimer() {
    let timeLeft = TIME_PER_QUESTION;
    timerText.textContent = formatTime(timeLeft);
    timerText.style.color = 'var(--text-secondary)'; // Reset color
    timerContainer.classList.remove('timer-low'); // Reset pulse animation

    questionTimerInterval = setInterval(() => {
        timeLeft--;
        timerText.textContent = formatTime(timeLeft);

        if (timeLeft <= 5) {
            timerText.style.color = 'var(--error-color)'; // Red color for urgency
            timerContainer.classList.add('timer-low');
        }

        if (timeLeft <= 0) {
            clearInterval(questionTimerInterval);
            handleTimeout();
        }
    }, 1000);
}

function handleTimeout() {
    // Treat timeout as an incorrect answer without selecting anything
    handleAnswer(null, null);
}

function loadQuestion() {
    const dict = uiTranslations[currentLang] || uiTranslations['en'];
    if (currentIndex >= targetQuestionCount && gameMode !== 'sprint') {
        showResults();
        return;
    }

    const nextQuestion = getNextQuestion();
    if (!nextQuestion) {
        showResults(); // Pool exhausted
        return;
    }
    
    currentTestQuestions[currentIndex] = nextQuestion;

    // Clear previous timer and start a new one
    clearInterval(questionTimerInterval);
    if (gameMode === 'standard') {
        startTimer();
    }

    const currentQuestion = currentTestQuestions[currentIndex];
    
    // Update text elements
    questionTextElement.textContent = currentQuestion.q;
    
    if (currentQuestion.img) {
        questionImageElement.src = currentQuestion.img;
        questionImageElement.classList.remove('hidden');
    } else {
        questionImageElement.classList.add('hidden');
        questionImageElement.src = "";
    }
    
    progressText.textContent = gameMode === 'sprint' ? `${dict.prog_points}${weightedScore}` : dict.prog_question.replace('{0}', currentIndex + 1).replace('{1}', targetQuestionCount);
    
    // Update the visual progress bar width
    const progressPercentage = gameMode === 'sprint' ? ((SPRINT_TIME - globalTimeLeft) / SPRINT_TIME) * 100 : (currentIndex / targetQuestionCount) * 100;
    progressFill.style.width = `${progressPercentage}%`;
    
    // Clear out old options from the previous question
    optionsContainer.innerHTML = "";
    optionsContainer.classList.remove("options-disabled"); // Re-enable clicks

    // Generate new buttons for the current question
    let randomizedOptions = shuffleArray([...currentQuestion.o]); // clone and shuffle
    randomizedOptions.forEach(option => {
        const button = document.createElement("button");
        button.textContent = option;
        button.classList.add("option-btn");
        
        // Store the value as a dataset attribute for easier validation later
        button.dataset.value = option;
        
        // When clicked, check the answer
        button.addEventListener("click", () => {
            SoundEngine.pop();
            SoundEngine.vibrate(30);
            handleAnswer(option, button);
        });
        
        optionsContainer.appendChild(button);
    });
}

function handleAnswer(selectedOption, selectedButton) {
    const dict = uiTranslations[currentLang] || uiTranslations['en'];
    // Stop the timer as soon as an answer is given or time runs out
    clearInterval(questionTimerInterval);

    const currentQuestion = currentTestQuestions[currentIndex];
    
    // Disable further clicking until the next question loads
    optionsContainer.classList.add("options-disabled");
    
    // Find the button that contains the correct answer
    const allButtons = optionsContainer.querySelectorAll(".option-btn");
    let correctButton = null;
    allButtons.forEach(btn => {
        if (btn.dataset.value === currentQuestion.a) {
            correctButton = btn;
        }
    });

    // Check answer (if an option was selected) and log result for the graph
    const isCorrect = selectedOption === currentQuestion.a;
    answerLog.push({
        question: currentQuestion.q,
        correct: isCorrect,
        userAnswer: selectedOption || dict.ans_timeout,
        correctAnswer: currentQuestion.a,
        explanation: currentQuestion.exp || dict.exp_default.replace('{0}', currentQuestion.a)
    });

    const qWeight = getWeight(currentQuestion.difficulty);
    maxPossibleScore += qWeight;

    if (isCorrect) {
        weightedScore += qWeight;
        
        if (isAdaptive) {
            adaptiveStreak++;
            if (adaptiveStreak >= 2) {
                if (currentDifficulty === 'beginner') currentDifficulty = 'intermediate';
                else if (currentDifficulty === 'intermediate') currentDifficulty = 'advanced';
                adaptiveStreak = 0;
            }
        }
        
        if (selectedButton) {
            selectedButton.classList.add("correct");
            mainAppContainer.classList.add("screen-flash-correct");
            SoundEngine.chime();
            SoundEngine.vibrate([50, 50, 50]);
        }
    } else {
        if (isAdaptive) {
            if (currentDifficulty === 'advanced') currentDifficulty = 'intermediate';
            else if (currentDifficulty === 'intermediate') currentDifficulty = 'beginner';
            adaptiveStreak = 0;
        }
        
        if (selectedButton) {
            selectedButton.classList.add("incorrect");
            mainAppContainer.classList.add("screen-shake-incorrect");
            SoundEngine.buzz();
            SoundEngine.vibrate(200);
        }
        // Always show the correct answer, even on timeout
        if (correctButton) correctButton.classList.add("correct");
    }

    currentIndex++;

    // Wait 1.5 seconds before moving on so the user sees the visual feedback
    setTimeout(() => {
        mainAppContainer.classList.remove("screen-flash-correct", "screen-shake-incorrect");
        
        // In sprint mode, if global timer died during the 1.5s delay, we shouldn't load another
        if (gameMode === 'sprint' && globalTimeLeft <= 0) return;
        
        loadQuestion();
    }, 1500);
}

function calculateAndDisplayIQ(achieved, possible) {
    if (possible === 0) {
        iqScoreValue.textContent = "N/A";
        return 0;
    }
    const percentage = (achieved / possible);
    // This is a simplified, non-clinical mapping of percentage to an IQ-like scale (70-150)
    const simulatedIQ = Math.round(70 + (percentage * 80));
    iqScoreValue.textContent = simulatedIQ;
    return simulatedIQ;
}

function updateHighScore(newScore) {
    const currentHighScore = parseInt(localStorage.getItem(HIGH_SCORE_KEY)) || 0;
    if (newScore > currentHighScore) {
        localStorage.setItem(HIGH_SCORE_KEY, newScore);
        displayHighScore();
    }
}

function fireConfetti() {
    const colors = ['#8b5cf6', '#06b6d4', '#10b981', '#ef4444', '#f59e0b'];
    for(let i=0; i<80; i++) {
        let conf = document.createElement('div');
        conf.classList.add('confetti-piece');
        conf.style.left = Math.random() * 100 + 'vw';
        conf.style.backgroundColor = colors[Math.floor(Math.random() * colors.length)];
        conf.style.animation = `confettiFall ${Math.random() * 3 + 2}s linear forwards`;
        conf.style.animationDelay = `${Math.random() * 1.5}s`;
        document.body.appendChild(conf);
        setTimeout(() => conf.remove(), 5000);
    }
}

function renderResultsGraph() {
    resultsGraphContainer.innerHTML = ""; // Clear previous graph
    answerLog.forEach(log => {
        const bar = document.createElement("div");
        bar.classList.add("result-bar");
        bar.classList.add(log.correct ? "correct" : "incorrect");
        bar.title = `Q: ${log.question}\nAnswer: ${log.correct ? 'Correct' : 'Incorrect'}`;
        resultsGraphContainer.appendChild(bar);
    });
}

function showResults() {
    const dict = uiTranslations[currentLang] || uiTranslations['en'];
    
    // Swap visibility of main areas
    clearInterval(questionTimerInterval); // Ensure timer is stopped
    clearInterval(globalTimerInterval);
    quizArea.classList.add("hidden");
    quizHeaderInfo.classList.add("hidden");
    terminateBtn.classList.add("hidden");
    resultArea.classList.remove("hidden");
    
    // Calculate and show simulated IQ
    const finalIQ = calculateAndDisplayIQ(weightedScore, maxPossibleScore);
    updateHighScore(finalIQ);

    SoundEngine.victory();
    if(weightedScore > 0) fireConfetti();

    // Display final score
    const percentage = maxPossibleScore > 0 ? Math.round((weightedScore / maxPossibleScore) * 100) : 0;
    
    let feedbackText = "";
    if (percentage === 100) feedbackText = dict.feedback_perfect;
    else if (percentage >= 75) feedbackText = dict.feedback_great;
    else if (percentage >= 50) feedbackText = dict.feedback_good;
    else feedbackText = dict.feedback_keepPracticing;

    scoreText.innerHTML = `${dict.score_earned.replace('{0}', weightedScore).replace('{1}', maxPossibleScore).replace('{2}', percentage)}<br><br>${feedbackText}<br><small>${dict.score_simulated}</small>`;
    
    // Render the visual graph of answers
    renderResultsGraph();
    
    // Render explanations for incorrect answers
    explanationsList.innerHTML = "";
    let hasIncorrect = false;

    answerLog.forEach(log => {
        if (!log.correct) {
            hasIncorrect = true;
            const card = document.createElement("div");
            card.classList.add("explanation-card");
            card.innerHTML = `
                <p><strong>${dict.q_label}</strong> ${log.question}</p>
                <p><strong>${dict.your_ans}</strong> <span style="color: var(--error-color);">${log.userAnswer}</span></p>
                <p><strong>${dict.correct_ans}</strong> <span style="color: var(--success-color);">${log.correctAnswer}</span></p>
                <p class="exp-text">${log.explanation}</p>
            `;
            explanationsList.appendChild(card);
        }
    });

    if (hasIncorrect) explanationsContainer.classList.remove("hidden");
    else explanationsContainer.classList.add("hidden");
}

function applyTheme(theme) {
    if (theme === 'light') {
        body.classList.add('light-mode');
        themeToggle.checked = true;
    } else {
        body.classList.remove('light-mode');
        themeToggle.checked = false;
    }
}

function toggleTheme() {
    const newTheme = body.classList.contains('light-mode') ? 'dark' : 'light';
    localStorage.setItem(THEME_KEY, newTheme);
    applyTheme(newTheme);
}

function loadInitialTheme() {
    const savedTheme = localStorage.getItem(THEME_KEY);
    // Check system preference as a fallback, otherwise default to dark
    const systemPrefersDark = window.matchMedia('(prefers-color-scheme: dark)').matches;
    const defaultTheme = systemPrefersDark ? 'dark' : 'light';
    applyTheme(savedTheme || defaultTheme);
}

function populateCategories() {
    const dict = uiTranslations[currentLang] || uiTranslations['en'];
    categorySelection.innerHTML = `<option value="all" data-i18n="allCategories">${dict.allCategories || "All Categories"}</option>`;
    
    const allCategories = new Set();
    Object.values(questionBank['en']).forEach(level => { // Use EN as base source of truth for categories
        Object.keys(level).forEach(category => {
            allCategories.add(category);
        });
    });

    allCategories.forEach(category => {
        const option = document.createElement('option');
        option.value = category;
        option.textContent = dict['cat_' + category] || (category.charAt(0).toUpperCase() + category.slice(1));
        categorySelection.appendChild(option);
    });
}

function displayHighScore() {
    const highScore = localStorage.getItem(HIGH_SCORE_KEY) || '0';
    highScoreDisplay.textContent = highScore;
}

function restartQuiz() {
    // This function now acts as a general reset to the config screen
    if (questionTimerInterval) clearInterval(questionTimerInterval);
    if (globalTimerInterval) clearInterval(globalTimerInterval);

    // Reset state variables
    currentIndex = 0;
    weightedScore = 0;
    maxPossibleScore = 0;
    currentTestQuestions = [];
    answerLog = [];
    
    // Swap visibility back to the config screen
    resultArea.classList.add("hidden");
    quizArea.classList.add("hidden");
    explanationsContainer.classList.add("hidden");
    quizHeaderInfo.classList.add("hidden");
    terminateBtn.classList.add("hidden");
    configArea.classList.remove("hidden");
    progressFill.style.width = "0%";

    // Ensure high score is up-to-date on the home screen
    displayHighScore();
}

function updateLanguage(lang) {
    currentLang = lang;
    const dict = uiTranslations[lang];
    
    // Update all elements with data-i18n attributes
    document.querySelectorAll('[data-i18n]').forEach(el => {
        const key = el.getAttribute('data-i18n');
        if(dict[key]) {
            if (el.tagName === 'INPUT' || el.tagName === 'TEXTAREA') {
                el.placeholder = dict[key];
            } else {
                el.textContent = dict[key];
            }
        }
    });
    populateCategories(); // Refresh categories
}

// --- Authentication Functions ---
onAuthStateChanged(auth, (user) => {
    if (user) {
        authContainer.classList.add('hidden');
        userInfoDisplay.textContent = user.email || user.displayName || "User";
        userInfoDisplay.style.display = "inline-block";
        
        // Check if user has previously accepted T&C on this device
        const termsAccepted = localStorage.getItem('termsAccepted_' + user.uid);
        if (termsAccepted === 'true') {
            tncContainer.classList.add('hidden');
            mainAppContainer.classList.remove('hidden');
        } else {
            // Show T&C screen, hide main app
            mainAppContainer.classList.add('hidden');
            tncContainer.classList.remove('hidden');
            
            // Reset checkbox and button state
            tncCheckbox.checked = false;
            tncAcceptBtn.disabled = true;
        }
    } else {
        // User is signed out, show login window, hide main app
        authContainer.classList.remove('hidden');
        mainAppContainer.classList.add('hidden');
        tncContainer.classList.add('hidden');
        userInfoDisplay.textContent = "";
        userInfoDisplay.style.display = "none";
        
        // Clear credentials and messages upon logout
        authEmail.value = '';
        authPassword.value = '';
        authPassword.type = 'password';
        authConfirmPassword.value = '';
        authConfirmPassword.type = 'password';
        authMessage.textContent = '';
        
        document.querySelectorAll('.password-toggle svg').forEach(svg => {
            svg.innerHTML = '<path d="M1 12s4-8 11-8 11 8 11 8-4 8-11 8-11-8-11-8z"></path><circle cx="12" cy="12" r="3"></circle>';
        });
        restartQuiz(); // Reset quiz state in case they log out mid-quiz
    }
});

// --- T&C Functions ---
tncCheckbox.addEventListener('change', (e) => {
    tncAcceptBtn.disabled = !e.target.checked;
});

tncAcceptBtn.addEventListener('click', () => {
    if (auth.currentUser && tncCheckbox.checked) {
        localStorage.setItem('termsAccepted_' + auth.currentUser.uid, 'true');
        tncContainer.classList.add('hidden');
        mainAppContainer.classList.remove('hidden');
    }
});

tncDeclineBtn.addEventListener('click', () => {
    signOut(auth).then(() => {
        setTimeout(() => {
            authMessage.textContent = "You must accept the Terms & Conditions to use IQ Master.";
            authMessage.style.color = "var(--error-color)";
        }, 50);
    });
});

let isLoginMode = true;

authSwitchLink.addEventListener('click', (e) => {
    e.preventDefault();
    isLoginMode = !isLoginMode;
    authMessage.textContent = "";
    const dict = uiTranslations[currentLang];
    
    if (isLoginMode) {
        authTitle.textContent = dict.welcomeBack;
        authSubtitle.textContent = dict.loginToContinue;
        confirmPasswordGroup.classList.add('hidden');
        forgotPasswordContainer.classList.remove('hidden');
        authSubmitBtn.textContent = dict.loginBtn;
        authSwitchText.textContent = dict.noAccount;
        authSwitchLink.textContent = dict.signUpLink;
        authConfirmPassword.removeAttribute('required');
    } else {
        authTitle.textContent = dict.createAccount;
        authSubtitle.textContent = dict.signupText;
        confirmPasswordGroup.classList.remove('hidden');
        forgotPasswordContainer.classList.add('hidden');
        authSubmitBtn.textContent = dict.alreadyAccount;
        authSwitchText.textContent = dict.alreadyAccount;
        authSwitchLink.textContent = dict.loginLink;
        authConfirmPassword.setAttribute('required', 'true');
    }
});

authForm.addEventListener('submit', (e) => {
    e.preventDefault(); // Prevents page reload
    
    const email = authEmail.value;
    const password = authPassword.value;
    const dict = uiTranslations[currentLang];
    SoundEngine.init(); // Initialize audio context on first meaningful user interaction

    authSubmitBtn.disabled = true;
    authSubmitBtn.innerHTML = `<span class="spinner"></span> ${dict.wait}`;
    authMessage.style.color = "var(--error-color)"; // Reset color to error for typical messages

    if (isLoginMode) {
        signInWithEmailAndPassword(auth, email, password)
            .then(() => { 
                authMessage.textContent = ""; 
                authSubmitBtn.disabled = false;
                authSubmitBtn.innerHTML = dict.loginBtn;
            })
            .catch((error) => { 
                authMessage.textContent = error.message.replace('Firebase: ', ''); 
                authSubmitBtn.disabled = false;
                authSubmitBtn.innerHTML = dict.loginBtn;
            });
    } else {
        if (password !== authConfirmPassword.value) {
            authMessage.textContent = dict.alert_pwdMatch;
            authSubmitBtn.disabled = false;
            authSubmitBtn.textContent = dict.signUpLink;
            return;
        }
        createUserWithEmailAndPassword(auth, email, password)
            .then(() => { 
                authMessage.textContent = dict.alert_regSuccess;
                authMessage.style.color = "var(--success-color)";
                authSubmitBtn.disabled = false;
                authSubmitBtn.innerHTML = dict.signUpLink;
            })
            .catch((error) => { 
                authMessage.textContent = error.message.replace('Firebase: ', ''); 
                authSubmitBtn.disabled = false;
                authSubmitBtn.innerHTML = dict.signUpLink;
            });
    }
});

// Forgot Password Functionality
forgotPasswordLink.addEventListener('click', (e) => {
    e.preventDefault();
    const email = authEmail.value.trim();
    const dict = uiTranslations[currentLang] || uiTranslations['en'];
    
    if (!email) {
        authMessage.textContent = dict.alert_enterEmail;
        authMessage.style.color = "var(--error-color)";
        return;
    }

    sendPasswordResetEmail(auth, email)
        .then(() => {
            authMessage.textContent = dict.alert_resetSent;
            authMessage.style.color = "var(--success-color)";
        })
        .catch((error) => {
            authMessage.textContent = error.message.replace('Firebase: ', '');
            authMessage.style.color = "var(--error-color)";
        });
});

// Initialize Google Auth Provider
const googleProvider = new GoogleAuthProvider();

googleLoginBtn.addEventListener('click', (e) => {
    e.preventDefault();
    SoundEngine.init();
    const originalContent = googleLoginBtn.innerHTML;
    const dict = uiTranslations[currentLang] || uiTranslations['en'];
    
    // Do not disable the button before opening the popup to avoid strict browser popup blockers
    googleLoginBtn.innerHTML = `<span class="spinner"></span> ${dict.wait}`;

    signInWithPopup(auth, googleProvider)
        .then(() => { 
            authMessage.textContent = ""; 
            googleLoginBtn.innerHTML = originalContent;
        })
        .catch((error) => { 
            authMessage.textContent = error.message.replace('Firebase: ', ''); 
            googleLoginBtn.innerHTML = originalContent;
        });
});

logoutBtn.addEventListener('click', () => {
    const dict = uiTranslations[currentLang] || uiTranslations['en'];
    signOut(auth).then(() => {
        setTimeout(() => {
            authMessage.textContent = dict.alert_logoutSuccess;
            authMessage.style.color = "var(--success-color)";
        }, 50); // Set slight delay so it displays after the input clearer runs
    }).catch((error) => {
        console.error("Logout Error:", error);
    });
});

// 5. Event Listeners and Initialization
startBtn.addEventListener("click", generateAndStartQuiz);
restartBtn.addEventListener("click", restartQuiz);
themeToggle.addEventListener('change', toggleTheme);
gameModeSelect.addEventListener('change', (e) => {
    questionCountSelect.disabled = e.target.value === 'sprint';
});
languageSelect.addEventListener('change', (e) => {
    updateLanguage(e.target.value);
    const dict = uiTranslations[currentLang] || uiTranslations['en'];
    // If a test is actively running, prompt to restart to apply question language
    if (!quizArea.classList.contains('hidden')) {
        if (confirm(dict.confirm_langChange)) {
            restartQuiz();
        }
    }
});
terminateBtn.addEventListener("click", () => {
    const dict = uiTranslations[currentLang] || uiTranslations['en'];
    if (confirm(dict.confirm_endTest)) {
        restartQuiz();
    }
});

// Fetch questions from external file and initialize app
fetch('questions.json')
    .then(response => {
        if (!response.ok) throw new Error("Failed to fetch questions");
        return response.json();
    })
    .then(data => {
        baseQuestionBank = data;
        questionBank = new Proxy(baseQuestionBank, {
            get: function(target, lang) {
                return target[lang] || target['en'];
            }
        });
        loadInitialTheme();
        displayHighScore();
        populateCategories();
        updateLanguage('en');
    })
    .catch(err => {
        console.error("Initialization Error:", err);
        authMessage.textContent = "Failed to load question bank. Ensure you are running a local server (like Live Server).";
    });

// Password Visibility Toggle
const passwordToggles = document.querySelectorAll('.password-toggle');
passwordToggles.forEach(toggle => {
    toggle.addEventListener('click', () => {
        const input = toggle.parentElement.querySelector('input');
        const svg = toggle.querySelector('svg');
        if (input.type === 'password') {
            input.type = 'text';
            svg.innerHTML = '<path d="M17.94 17.94A10.07 10.07 0 0 1 12 20c-7 0-11-8-11-8a18.45 18.45 0 0 1 5.06-5.94M9.9 4.24A9.12 9.12 0 0 1 12 4c7 0 11 8 11 8a18.5 18.5 0 0 1-2.16 3.19m-6.72-1.07a3 3 0 1 1-4.24-4.24"></path><line x1="1" y1="1" x2="23" y2="23"></line>';
        } else {
            input.type = 'password';
            svg.innerHTML = '<path d="M1 12s4-8 11-8 11 8 11 8-4 8-11 8-11-8-11-8z"></path><circle cx="12" cy="12" r="3"></circle>';
        }
    });
});