---
layout: default
title: "Home"
icon: "🏠"
hide_toc: true
---
<style>
    .hero-section {
        height: 100vh;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        text-align: center;
        background: var(--hero-glow);
        width: 100%;
        margin: 0;
        padding-bottom: 15vh; /* Shift content up optically */
    }

    .hero-title {
        font-size: 4.2rem;
        font-weight: 900;
        margin-bottom: 30px;
        background: linear-gradient(to bottom, #ffffff, #67e8f9); /* Crisp white to bright ice blue */
        -webkit-background-clip: text;
        background-clip: text;
        -webkit-text-fill-color: transparent;
        letter-spacing: -3px;
        line-height: 1.2;
        padding-bottom: 0.1em;
    }

    .hero-subtitle {
        color: var(--muted);
        font-size: 1.2rem;
        max-width: 700px;
        margin: -10px auto 40px auto;
        line-height: 1.6;
    }

    .category-grid {
        display: grid;
        grid-template-columns: repeat(3, 1fr);
        gap: 20px;
        max-width: 720px;
        width: 100%;
        margin: 0 auto;
    }

    .category-box {
        font-family: inherit;
        background: var(--surface-soft);
        border: 1px solid var(--border);
        border-radius: 20px;
        padding: 25px 15px;
        text-align: center;
        cursor: pointer;
        transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        text-decoration: none;
        color: inherit;
        backdrop-filter: blur(16px);
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        height: 150px;
    }

    .category-box:hover,
    .category-box:focus-visible {
        transform: translateY(-8px);
        background: var(--surface-hover);
        border-color: var(--primary);
        box-shadow: 0 20px 40px rgba(0,0,0,0.3);
    }

    .category-box i {
        font-size: 3.2rem;
        margin-bottom: 20px;
        display: block;
    }

    .category-box span {
        font-weight: 700;
        font-size: 1.3rem;
        color: var(--text);
    }

    .results-container {
        position: fixed;
        top: 0;
        left: 0;
        width: 100vw;
        height: 100vh;
        background: var(--bg);
        z-index: 999;
        display: none;
        padding: 60px;
        overflow-y: auto;
        opacity: 0;
        transition: opacity 0.2s ease;
        pointer-events: none;
    }

    .results-container.active {
        display: block;
        opacity: 1;
        pointer-events: auto;
    }

    .lesson-list {
        display: flex;
        flex-direction: column;
        gap: 10px;
        max-width: 820px;
        margin: 20px auto 0 auto;
    }

    /* Extra specificity: the global `.content a` link styling (underline,
       accent colour) must not bleed into lesson rows */
    .content .lesson-row,
    .content .lesson-row:hover {
        display: flex;
        align-items: center;
        gap: 16px;
        padding: 14px 22px;
        background: var(--surface-soft);
        border: 1px solid var(--border);
        border-radius: 16px;
        text-decoration: none;
        color: var(--text);
        font-weight: 400;
        transition: all 0.2s ease;
    }

    .content .lesson-row:hover {
        background: var(--surface-hover);
        border-color: var(--accent);
        transform: translateX(6px);
    }

    .lesson-num {
        min-width: 2em;
        text-align: right;
        font-weight: 800;
        font-size: 0.95rem;
        color: var(--muted);
        font-variant-numeric: tabular-nums;
    }

    .lesson-row-icon {
        font-size: 1.25rem;
    }

    .lesson-row h3 {
        margin: 0;
        font-size: 1.1rem;
        line-height: 1.4;
        color: var(--text);
        flex: 1;
        text-align: left; /* the hero section centers text; lesson titles scan better left-aligned */
        font-weight: 700;
    }

    .lesson-row:hover h3 {
        color: var(--accent);
    }

    .lesson-cat {
        font-size: 0.8rem;
        color: var(--muted);
        text-transform: uppercase;
        letter-spacing: 1px;
        white-space: nowrap;
    }

    .unit-header {
        display: flex;
        align-items: center;
        gap: 12px;
        max-width: 820px;
        margin: 48px auto 0 auto;
    }

    .unit-header:first-child {
        margin-top: 24px;
    }

    .unit-header-icon {
        font-size: 1.4rem;
    }

    .unit-header-name {
        font-size: 1.15rem;
        font-weight: 800;
        color: var(--accent);
        text-transform: uppercase;
        letter-spacing: 0.08em;
        white-space: nowrap;
    }

    .unit-header-rule {
        flex: 1;
        height: 1px;
        background: linear-gradient(to right, rgba(34, 211, 238, 0.35), transparent);
    }

    .unit-stats {
        font-size: 0.85rem;
        font-weight: 600;
        color: var(--muted);
        white-space: nowrap;
    }

    .score-badge {
        min-width: 3.4em;
        text-align: center;
        font-weight: 800;
        font-size: 0.95rem;
        font-variant-numeric: tabular-nums;
        color: var(--muted);
        padding: 4px 12px;
        border-radius: 999px;
        border: 1px solid transparent;
    }

    .score-badge.attempted {
        color: #cfeefc;
        border-color: rgba(34, 211, 238, 0.3);
        background: rgba(34, 211, 238, 0.08);
    }

    .score-badge.perfect {
        color: #b8f2d5;
        border-color: rgba(34, 197, 129, 0.45);
        background: rgba(34, 197, 129, 0.1);
    }

    .quiz-chip {
        font-family: inherit;
        font-size: 0.9rem;
        font-weight: 700;
        color: var(--muted);
        background: rgba(255, 255, 255, 0.05);
        border: 1px solid var(--border);
        border-radius: 999px;
        padding: 6px 16px;
        cursor: pointer;
        transition: all 0.2s ease;
    }

    .quiz-chip:hover {
        color: #fff;
        border-color: rgba(34, 211, 238, 0.45);
        background: rgba(34, 211, 238, 0.12);
    }

    .quiz-chip.attempted {
        color: #cfeefc;
        border-color: rgba(34, 211, 238, 0.3);
    }

    .quiz-chip.perfect {
        color: #b8f2d5;
        border-color: rgba(34, 197, 129, 0.45);
        background: rgba(34, 197, 129, 0.1);
    }

    .continue-pill {
        display: none;
        align-items: center;
        gap: 10px;
        margin: -16px auto 28px auto;
        padding: 10px 24px;
        width: fit-content;
        background: rgba(34, 211, 238, 0.1);
        border: 1px solid rgba(34, 211, 238, 0.35);
        border-radius: 999px;
        color: var(--accent);
        font-weight: 700;
        font-size: 1rem;
        text-decoration: none;
        transition: all 0.2s ease;
    }

    .continue-pill.show {
        display: inline-flex;
    }

    .continue-pill:hover {
        background: rgba(34, 211, 238, 0.18);
        color: #fff;
        transform: translateY(-2px);
    }

    .search-container {
        max-width: 550px;
        width: 100%;
        margin: 0 auto 35px auto;
        position: relative;
    }

    .search-input {
        width: 100%;
        background: var(--surface-soft);
        border: 2px solid var(--border);
        border-radius: 999px;
        padding: 18px 30px 18px 60px;
        font-size: 1.1rem;
        color: var(--text);
        outline: none;
        transition: all 0.3s;
        backdrop-filter: blur(10px);
    }

    .search-input:focus {
        background: var(--surface-hover);
        border-color: var(--primary);
        box-shadow: var(--shadow);
    }

    .search-icon {
        position: absolute;
        left: 25px;
        top: 50%;
        transform: translateY(-50%);
        font-size: 1.2rem;
        opacity: 0.5;
    }

    .no-results {
        text-align: center;
        padding: 40px;
        opacity: 0.6;
    }

    @keyframes fadeIn {
        from { opacity: 0; transform: translateY(20px); }
        to { opacity: 1; transform: translateY(0); }
    }

    /* Small screens: let the portal scroll and stack the category tiles */
    @media (max-width: 820px) {
        body.home-page {
            overflow: auto;
        }

        .hero-section {
            height: auto;
            min-height: 100vh;
            padding: 60px 20px 10vh;
        }

        .hero-title {
            font-size: 2.6rem;
            letter-spacing: -1px;
        }

        .hero-subtitle {
            font-size: 1.15rem;
            margin-bottom: 40px;
        }

        .category-grid {
            grid-template-columns: repeat(2, 1fr);
            max-width: 500px;
        }

        .results-container {
            padding: 30px 16px;
        }
    }
</style>
<div class="hero-section">
    <h1 class="hero-title">LTF Teaching Archives</h1>
    <p class="hero-subtitle">Grammar lessons, skill guides and self-check quizzes for English learners.</p>

    <div class="search-container">
        <span class="search-icon">🔍</span>
        <input type="text" id="searchInput" class="search-input" placeholder="Search lessons and quizzes..." aria-label="Search lessons and quizzes" oninput="handleSearch(this.value)">
    </div>

    <a id="continuePill" class="continue-pill" href="#"></a>

    <div class="category-grid" id="categoryGrid">
        <button type="button" class="category-box" onclick="filterCategory('Grammar')">
            <i>🧩</i>
            <span>Grammar</span>
        </button>
        <button type="button" class="category-box" onclick="filterCategory('Reading')">
            <i>📖</i>
            <span>Reading</span>
        </button>
        <button type="button" class="category-box" onclick="filterCategory('Writing')">
            <i>✍️</i>
            <span>Writing</span>
        </button>
        <button type="button" class="category-box" onclick="filterCategory('Listening')">
            <i>🎧</i>
            <span>Listening</span>
        </button>
        <button type="button" class="category-box" onclick="filterCategory('Speaking')">
            <i>🗣️</i>
            <span>Speaking</span>
        </button>
        <button type="button" class="category-box" onclick="filterCategory('Quizzes')">
            <i>📝</i>
            <span>Quizzes</span>
        </button>
    </div>

    <div id="resultsWrapper" class="results-container">
        <div style="display: flex; justify-content: space-between; align-items: center; margin-bottom: 30px; border-bottom: 1px solid rgba(255,255,255,0.1); padding-bottom: 15px;">
            <h2 id="resultsTitle" style="margin: 0; font-size: 1.5rem; color: var(--primary);">Resources</h2>
            <button id="closeResultsBtn" onclick="closeResults()" style="background: none; border: none; color: #ff6b6b; cursor: pointer; font-weight: bold; font-size: 1.1rem;">✕ Close</button>
        </div>
        <div id="list"></div>
    </div>
</div>

<script>
    let resources = [];
    let curriculumData = {};

    async function init() {
        try {
            const [resResp, curResp] = await Promise.all([
                fetch('{{ "/assets/js/search-data.json" | relative_url }}'),
                fetch('{{ "/assets/js/curriculum.json" | relative_url }}')
            ]);
            resources = await resResp.json();
            resources.sort((a, b) => a.title.localeCompare(b.title));
            try { curriculumData = await curResp.json() || {}; } catch (e) { curriculumData = {}; }

            console.log('📦 Search index built with ' + resources.length + ' items');

            showContinuePill();

            // Handle incoming category filter from URL (Smart Back)
            handleHashNavigation();
        } catch (e) {
            console.error('Failed to load search data:', e);
        }
    }

    function handleHashNavigation() {
        const hash = window.location.hash;
        console.log('🔎 Checking hash navigation:', hash);
        if (hash.startsWith('#cat=')) {
            const cat = decodeURIComponent(hash.substring(5));
            if (cat) {
                console.log('🎯 Smart Back: Filtering for category:', cat);
                filterCategory(cat);
                // Clear the hash after a short delay to ensure it's not re-triggered but looks clean
                setTimeout(() => {
                    window.history.replaceState(null, null, window.location.pathname);
                }, 100);
            }
        }
    }

    window.addEventListener('hashchange', handleHashNavigation);

    init();

    // Keyboard shortcuts
    window.addEventListener('keydown', (e) => {
        if (e.key === 'Escape') {
            closeResults();
        }
    });

    function filterCategory(cat) {
        if (resources.length === 0) {
            setTimeout(() => filterCategory(cat), 100);
            return;
        }
        renderList(cat);
    }

    let lastFocusedElement = null;

    function closeResults() {
        const wrapper = document.getElementById('resultsWrapper');
        wrapper.style.opacity = '0';

        setTimeout(() => {
            wrapper.classList.remove('active');
            wrapper.style.display = 'none';
            document.getElementById('categoryGrid').style.opacity = '1';
        }, 200);
        window.scrollTo({ top: 0, behavior: 'smooth' });
        // Return keyboard focus to wherever the overlay was opened from
        if (lastFocusedElement && document.contains(lastFocusedElement)) {
            lastFocusedElement.focus();
        }
    }

    let searchTimeout;
    function handleSearch(query) {
        clearTimeout(searchTimeout);
        searchTimeout = setTimeout(() => {
            if (!query.trim()) {
                closeResults();
                return;
            }
            renderList('Search Results', query.trim().toLowerCase());
        }, 300);
    }

    function renderList(categoryFilter, searchQuery = null) {
        const container = document.getElementById('list');
        const wrapper = document.getElementById('resultsWrapper');
        const grid = document.getElementById('categoryGrid');
        const titleEl = document.getElementById('resultsTitle');

        if (!container || !wrapper || !grid || !titleEl) return;

        container.innerHTML = '';
        titleEl.innerText = searchQuery ? `Results for "${searchQuery}"` : categoryFilter;
        if (!wrapper.classList.contains('active')) {
            lastFocusedElement = document.activeElement;
        }
        wrapper.style.display = 'block';
        wrapper.style.opacity = '1';
        wrapper.offsetHeight; // Force reflow
        wrapper.classList.add('active');
        grid.style.opacity = '0.3';
        // Move keyboard focus into the overlay (unless the user is mid-search)
        if (!searchQuery) {
            document.getElementById('closeResultsBtn').focus();
        }

        const units = !searchQuery && curriculumData[categoryFilter.toLowerCase()];

        if (!searchQuery && categoryFilter === 'Quizzes' && curriculumData.grammar) {
            renderQuizDashboard(container);
        } else if (units && units.length) {
            // Curriculum view: numbered lesson rows under unit headers, in teaching order
            const byUrl = {};
            resources.forEach(r => { byUrl[r.url] = r; });
            const listed = new Set();
            let lessonNum = 0;

            units.forEach(unit => {
                const lessons = (unit.lessons || [])
                    .map(l => ({ res: byUrl[l.slug], quiz: l.quiz }))
                    .filter(x => x.res);
                if (!lessons.length) return;
                container.appendChild(makeUnitHeader(unit.icon, unit.unit));
                const list = makeList();
                lessons.forEach(({ res, quiz }) => {
                    lessonNum++;
                    list.appendChild(makeLessonRow(res, { quiz, num: lessonNum }));
                    listed.add(res.url);
                    // A paired quiz is reachable via its lesson's chip; don't
                    // duplicate it as a leftover row (matters when the quiz
                    // shares the lesson's category, e.g. Reading practice)
                    if (quiz) listed.add(quiz);
                });
                container.appendChild(list);
            });

            // Fail-soft: pages of this category missing from curriculum.yml
            // still show up rather than silently disappearing
            const leftovers = resources.filter(r => r.category === categoryFilter && !listed.has(r.url));
            if (leftovers.length) {
                container.appendChild(makeUnitHeader('📂', 'More resources'));
                const list = makeList();
                leftovers.forEach(res => list.appendChild(makeLessonRow(res, {})));
                container.appendChild(list);
            }
        } else {
            let filtered = [];
            if (searchQuery) {
                const queryLower = searchQuery.toLowerCase();
                // Unit names count as search terms: "linking" finds the connectives unit
                const unitSlugs = new Set();
                Object.values(curriculumData).forEach(catUnits => catUnits.forEach(u => {
                    if ((u.unit || '').toLowerCase().includes(queryLower)) {
                        (u.lessons || []).forEach(l => { unitSlugs.add(l.slug); if (l.quiz) unitSlugs.add(l.quiz); });
                    }
                }));
                // Otherwise strict title-only search (no full-text noise)
                filtered = resources.filter(res =>
                    res.title.toLowerCase().includes(queryLower) || unitSlugs.has(res.url)
                );
            } else {
                filtered = resources
                    .filter(res => res.category === categoryFilter)
                    .sort((a, b) => (a.order || 999) - (b.order || 999) || a.title.localeCompare(b.title));
            }

            if (filtered.length === 0) {
                container.innerHTML = '<div class="no-results">No resources found matching your criteria.</div>';
            } else {
                const list = makeList();
                // Show the category tag on search results (mixed categories)
                filtered.forEach(res => list.appendChild(makeLessonRow(res, { showCategory: !!searchQuery })));
                container.appendChild(list);
            }
        }

        // Always scroll to results for better UX
        wrapper.scrollIntoView({ behavior: 'smooth', block: 'start' });
    }

    function showContinuePill() {
        try {
            const last = JSON.parse(localStorage.getItem('ltf-last-lesson'));
            if (!last || !last.url || !last.title) return;
            const pill = document.getElementById('continuePill');
            pill.href = last.url;
            pill.textContent = '▶ Continue: ' + last.title;
            pill.classList.add('show');
        } catch (e) { /* nothing to continue */ }
    }

    function makeList() {
        const list = document.createElement('div');
        list.className = 'lesson-list';
        return list;
    }

    function makeUnitHeader(icon, name, stats = null) {
        const h = document.createElement('div');
        h.className = 'unit-header';
        h.innerHTML = `<span class="unit-header-icon"></span><span class="unit-header-name"></span><span class="unit-header-rule"></span>`;
        h.querySelector('.unit-header-icon').textContent = icon || '📂';
        h.querySelector('.unit-header-name').textContent = name;
        if (stats) {
            const s = document.createElement('span');
            s.className = 'unit-stats';
            s.textContent = stats;
            h.appendChild(s);
        }
        return h;
    }

    function getQuizBest(quizUrl) {
        try {
            const saved = JSON.parse(localStorage.getItem('ltf-quiz:' + quizUrl));
            const best = saved && (saved.best || saved);
            if (best && typeof best.score === 'number') return best;
        } catch (e) { /* no saved attempt */ }
        return null;
    }

    // The Quizzes tab is a progress dashboard: grammar units mirrored from
    // curriculum.yml, one row per quiz with the student's best score
    function renderQuizDashboard(container) {
        const byUrl = {};
        resources.forEach(r => { byUrl[r.url] = r; });
        const listed = new Set();
        let num = 0;

        (curriculumData.grammar || []).forEach(unit => {
            const entries = (unit.lessons || []).filter(l => l.quiz && byUrl[l.quiz]);
            if (!entries.length) return;

            let attempted = 0, perfect = 0;
            entries.forEach(l => {
                const best = getQuizBest(l.quiz);
                if (best) { attempted++; if (best.score === best.total) perfect++; }
            });
            const stats = attempted
                ? `${attempted}/${entries.length} attempted · ${perfect} perfect`
                : `${entries.length} ${entries.length === 1 ? 'quiz' : 'quizzes'}`;

            container.appendChild(makeUnitHeader(unit.icon, unit.unit, stats));
            const list = makeList();
            entries.forEach(l => {
                num++;
                list.appendChild(makeQuizRow(byUrl[l.quiz], l.slug, num));
                listed.add(l.quiz);
            });
            container.appendChild(list);
        });

        // Fail-soft: quizzes not paired in curriculum.yml still show up
        const leftovers = resources.filter(r => r.category === 'Quizzes' && !listed.has(r.url));
        if (leftovers.length) {
            container.appendChild(makeUnitHeader('📂', 'More quizzes'));
            const list = makeList();
            leftovers.forEach(res => list.appendChild(makeLessonRow(res, {})));
            container.appendChild(list);
        }
    }

    function makeQuizRow(quizRes, lessonUrl, num) {
        const row = document.createElement('a');
        row.className = 'lesson-row';
        row.href = quizRes.url;

        const numSpan = document.createElement('span');
        numSpan.className = 'lesson-num';
        numSpan.textContent = num;
        row.appendChild(numSpan);

        const iconSpan = document.createElement('span');
        iconSpan.className = 'lesson-row-icon';
        iconSpan.textContent = quizRes.icon || '📝';
        row.appendChild(iconSpan);

        const titleH3 = document.createElement('h3');
        titleH3.textContent = quizRes.title.replace(/^Quiz:\s*/i, '');
        row.appendChild(titleH3);

        const best = getQuizBest(quizRes.url);
        const badge = document.createElement('span');
        badge.className = 'score-badge' + (best ? (best.score === best.total ? ' perfect' : ' attempted') : '');
        badge.textContent = best ? `${best.score}/${best.total}` : '—';
        row.appendChild(badge);

        if (lessonUrl) {
            const chip = document.createElement('button');
            chip.type = 'button';
            chip.className = 'quiz-chip';
            chip.textContent = '📖 Lesson';
            chip.onclick = (e) => {
                e.preventDefault();
                e.stopPropagation();
                window.location.href = lessonUrl;
            };
            row.appendChild(chip);
        }

        return row;
    }

    function makeLessonRow(res, { quiz = null, num = null, showCategory = false } = {}) {
        const row = document.createElement('a');
        row.className = 'lesson-row';
        row.href = res.url || "#";

        if (num !== null) {
            const numSpan = document.createElement('span');
            numSpan.className = 'lesson-num';
            numSpan.textContent = num;
            row.appendChild(numSpan);
        }

        const iconSpan = document.createElement('span');
        iconSpan.className = 'lesson-row-icon';
        iconSpan.textContent = res.icon || '📄';
        row.appendChild(iconSpan);

        const titleH3 = document.createElement('h3');
        titleH3.textContent = res.title;
        row.appendChild(titleH3);

        if (quiz) {
            // A nested anchor is invalid HTML, so the quiz chip is a button
            // that navigates on its own and never triggers the row link
            const chip = document.createElement('button');
            chip.type = 'button';
            chip.className = 'quiz-chip';
            chip.textContent = '📝 Quiz';
            // Surface the student's best saved score (written by quiz-engine.js)
            const best = getQuizBest(quiz);
            if (best) {
                chip.textContent = `📝 ${best.score}/${best.total}`;
                chip.classList.add(best.score === best.total ? 'perfect' : 'attempted');
            }
            chip.onclick = (e) => {
                e.preventDefault();
                e.stopPropagation();
                window.location.href = quiz;
            };
            row.appendChild(chip);
        } else if (showCategory) {
            const categorySpan = document.createElement('span');
            categorySpan.className = 'lesson-cat';
            categorySpan.textContent = res.category;
            row.appendChild(categorySpan);
        }

        return row;
    }
</script>