feat(alg9 phase5 final): итоговая шпаргалка + 7 боссов + ачивка «Магистр алгебры 9»

2026-05-29 09:10:01 +03:00
parent e1d4a1e38a
commit 1c93eb668e
1 changed files with 470 additions and 2 deletions
@@ -8,6 +8,9 @@
 <meta name="viewport" content="width=device-width,initial-scale=1.0">
 <title>Алгебра 9 класс — учебник</title>
 <link href="https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800;900&family=Inter:wght@400;500;600;700&family=Unbounded:wght@400;700;800;900&display=swap" rel="stylesheet">
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.16.9/dist/katex.min.css">
+<script defer src="https://cdn.jsdelivr.net/npm/katex@0.16.9/dist/katex.min.js"></script>
+<script defer src="https://cdn.jsdelivr.net/npm/katex@0.16.9/dist/contrib/auto-render.min.js"></script>
 <script src="/js/api.js" defer></script>
 <script src="/js/xp.js" defer></script>
 <style>
@@ -108,6 +111,90 @@ main{max-width:1100px;margin:0 auto;padding:32px 24px 60px}
 .ach-strip.lit .ach-title{color:#92400e}

 .foot{text-align:center;padding:24px 16px;color:var(--muted);font-size:.78rem;border-top:1px solid var(--border)}
+
+/* COURSE FINAL */
+.final-wrap{margin:0 0 28px;background:var(--card);border:1.5px solid var(--border);border-radius:18px;overflow:hidden;box-shadow:var(--sh)}
+.final-head{padding:18px 22px;background:linear-gradient(135deg,#3730a3 0%,#4f46e5 55%,#7c3aed 100%);color:#fff;cursor:pointer;display:flex;align-items:center;gap:14px;user-select:none;transition:filter .15s}
+.final-head:hover{filter:brightness(1.06)}
+.final-head-icon{width:46px;height:46px;border-radius:12px;background:rgba(255,255,255,.18);display:flex;align-items:center;justify-content:center;flex-shrink:0}
+.final-head-icon svg{width:26px;height:26px;stroke:#fff;fill:none;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
+.final-head-text{flex:1;min-width:0}
+.final-head-tag{display:inline-block;padding:3px 9px;background:rgba(255,255,255,.22);border-radius:99px;font-size:.7rem;font-weight:700;text-transform:uppercase;letter-spacing:.08em;margin-bottom:4px}
+.final-head-title{font-family:'Outfit',sans-serif;font-size:1.18rem;font-weight:800;letter-spacing:-.01em;line-height:1.25}
+.final-head-sub{font-size:.84rem;opacity:.88;margin-top:2px}
+.final-chevron{flex-shrink:0;transition:transform .25s}
+.final-chevron svg{width:24px;height:24px;stroke:#fff;fill:none;stroke-width:2.4;stroke-linecap:round;stroke-linejoin:round}
+.final-wrap.open .final-chevron{transform:rotate(180deg)}
+.final-body{display:none;padding:22px}
+.final-wrap.open .final-body{display:block}
+
+.fin-section-title{font-family:'Outfit',sans-serif;font-size:1.18rem;font-weight:800;color:var(--text);margin:8px 0 14px;letter-spacing:-.005em;display:flex;align-items:center;gap:9px}
+.fin-section-title svg{width:20px;height:20px;stroke:var(--pri);fill:none;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
+
+/* CHEAT SHEET */
+.cheat-grid{display:grid;grid-template-columns:1fr;gap:14px;margin-bottom:28px}
+@media(min-width:680px){.cheat-grid{grid-template-columns:1fr 1fr}}
+.cheat-card{border:1.5px solid var(--border);border-radius:13px;padding:14px 16px;background:var(--card);position:relative;overflow:hidden}
+.cheat-card::before{content:'';position:absolute;left:0;top:0;bottom:0;width:4px}
+.cheat-card.c1::before{background:linear-gradient(180deg,var(--ch1),var(--ch1-d))}
+.cheat-card.c2::before{background:linear-gradient(180deg,var(--ch2),var(--ch2-d))}
+.cheat-card.c3::before{background:linear-gradient(180deg,var(--ch3),var(--ch3-d))}
+.cheat-card.c4::before{background:linear-gradient(180deg,var(--ch4),var(--ch4-d))}
+.cheat-head{display:flex;align-items:center;gap:9px;margin-bottom:9px;padding-left:6px}
+.cheat-badge{font-size:.7rem;font-weight:800;padding:2px 8px;border-radius:99px;color:#fff;letter-spacing:.05em;text-transform:uppercase}
+.cheat-card.c1 .cheat-badge{background:var(--ch1)}
+.cheat-card.c2 .cheat-badge{background:var(--ch2)}
+.cheat-card.c3 .cheat-badge{background:var(--ch3)}
+.cheat-card.c4 .cheat-badge{background:var(--ch4)}
+.cheat-title{font-weight:800;color:var(--text);font-size:.98rem}
+.cheat-list{list-style:none;padding-left:6px;margin:0}
+.cheat-list li{padding:6px 0;border-bottom:1px dashed var(--border);font-size:.92rem;line-height:1.5;color:var(--text)}
+.cheat-list li:last-child{border-bottom:0}
+
+/* BOSS PROGRESS */
+.boss-overall-bar{background:linear-gradient(135deg,rgba(79,70,229,.08),rgba(124,58,237,.06));border:1px solid var(--border);border-radius:12px;padding:13px 16px;margin:6px 0 18px;display:flex;gap:14px;align-items:center;flex-wrap:wrap}
+.boss-overall-bar .lab{font-weight:700;font-size:.95rem;color:var(--text);min-width:200px}
+.boss-overall-bar .bar{flex:1;min-width:160px;height:9px;background:rgba(79,70,229,.12);border-radius:5px;overflow:hidden}
+.boss-overall-bar .fill{height:100%;background:linear-gradient(90deg,#4f46e5,#7c3aed,#f59e0b);transition:width .5s;border-radius:5px}
+
+/* BOSS CARDS */
+.boss-card{background:var(--card);border:2px solid var(--border);border-radius:14px;padding:16px;margin-bottom:14px;transition:border-color .35s,box-shadow .35s,transform .2s}
+.boss-card.solved{border-color:#10b981;box-shadow:0 0 0 3px rgba(16,185,129,.18)}
+.boss-head{display:flex;align-items:center;gap:10px;margin-bottom:10px;flex-wrap:wrap}
+.boss-tag{font-size:.7rem;font-weight:800;padding:3px 9px;border-radius:99px;background:rgba(79,70,229,.12);color:var(--pri-d);letter-spacing:.04em;text-transform:uppercase}
+html.dark .boss-tag{color:#c7d2fe}
+.boss-title{font-family:'Outfit',sans-serif;font-weight:800;color:var(--text);font-size:1.02rem;flex:1;min-width:0}
+.boss-q{padding:12px 14px;background:rgba(79,70,229,.06);border-radius:10px;font-size:.96rem;line-height:1.55;margin-bottom:10px;color:var(--text)}
+.boss-row{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-bottom:6px}
+.boss-input{padding:8px 12px;border:1.5px solid var(--border);border-radius:8px;background:var(--card);color:var(--text);font-family:'JetBrains Mono',monospace;width:130px;text-align:center;font-size:.95rem;transition:border-color .15s}
+.boss-input:focus{outline:0;border-color:var(--pri);box-shadow:0 0 0 3px var(--pri-soft)}
+.boss-btn{padding:8px 16px;border-radius:9px;background:var(--card);color:var(--text);border:1.5px solid var(--border);font-weight:700;font-size:.88rem;cursor:pointer;font-family:inherit;transition:background .15s,border-color .15s,transform .1s}
+.boss-btn:hover{background:var(--pri-soft);border-color:var(--pri)}
+.boss-btn:active{transform:scale(.96)}
+.boss-btn.primary{background:linear-gradient(135deg,var(--pri),#7c3aed);color:#fff;border-color:transparent}
+.boss-btn.primary:hover{filter:brightness(1.08)}
+.boss-fb{padding:10px 14px;border-radius:9px;font-weight:600;font-size:.88rem;margin-top:8px;display:none;line-height:1.45}
+.boss-fb.ok{display:block;background:#d1fae5;color:#065f46;border-left:4px solid #10b981}
+.boss-fb.fail{display:block;background:#fee2e2;color:#7f1d1d;border-left:4px solid #dc2626}
+html.dark .boss-fb.ok{background:rgba(16,185,129,.18);color:#a7f3d0}
+html.dark .boss-fb.fail{background:rgba(220,38,38,.18);color:#fecaca}
+.boss-hint-txt{margin-top:8px;padding:9px 13px;background:rgba(245,158,11,.12);border-left:3px solid #f59e0b;border-radius:6px;font-size:.86rem;color:var(--text);display:none;line-height:1.5}
+.boss-hint-txt.show{display:block}
+
+/* FINAL CTA */
+.final-cta{margin-top:24px;padding:18px 20px;border-radius:14px;background:linear-gradient(135deg,#fef3c7,#fde68a);border:1.5px solid #fbbf24;display:none;align-items:center;gap:14px;flex-wrap:wrap}
+.final-cta.show{display:flex}
+html.dark .final-cta{background:linear-gradient(135deg,rgba(245,158,11,.18),rgba(217,119,6,.15));border-color:#d97706}
+.final-cta-icon{width:48px;height:48px;border-radius:12px;background:linear-gradient(135deg,#fbbf24,#f59e0b);display:flex;align-items:center;justify-content:center;flex-shrink:0}
+.final-cta-icon svg{width:28px;height:28px;stroke:#fff;fill:none;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
+.final-cta-txt{flex:1;min-width:180px}
+.final-cta-title{font-weight:800;color:#92400e;font-size:1.05rem;font-family:'Outfit',sans-serif}
+html.dark .final-cta-title{color:#fde68a}
+.final-cta-sub{font-size:.86rem;color:#78350f;margin-top:2px}
+html.dark .final-cta-sub{color:#fcd34d}
+.final-cta-btn{padding:10px 18px;border-radius:10px;background:linear-gradient(135deg,#4f46e5,#7c3aed);color:#fff;text-decoration:none;font-weight:800;font-size:.9rem;display:inline-flex;align-items:center;gap:7px;transition:filter .15s}
+.final-cta-btn:hover{filter:brightness(1.1)}
+.final-cta-btn svg{width:16px;height:16px;stroke:currentColor;fill:none;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
 </style>
 </head>
 <body>
@@ -229,6 +316,103 @@ main{max-width:1100px;margin:0 auto;padding:32px 24px 60px}

  </div>

+  <section class="final-wrap" id="course-final">
+    <div class="final-head" id="final-head" tabindex="0" role="button" aria-expanded="false" aria-controls="final-body">
+      <div class="final-head-icon">
+        <svg viewBox="0 0 24 24"><path d="M7 4h10v6a5 5 0 0 1-10 0V4z"/><path d="M5 4h2v2H5a2 2 0 0 1 0-4M19 4h-2v2h2a2 2 0 0 0 0-4M9 20h6M12 15v5"/></svg>
+      </div>
+      <div class="final-head-text">
+        <div class="final-head-tag">Финал курса</div>
+        <div class="final-head-title">Босс-проверка по всему курсу</div>
+        <div class="final-head-sub" id="final-head-sub">Итоговая шпаргалка + 7 интегрированных боссов. Победи всех — получи «Магистр алгебры 9» и +50 XP.</div>
+      </div>
+      <div class="final-chevron"><svg viewBox="0 0 24 24"><polyline points="6 9 12 15 18 9"/></svg></div>
+    </div>
+
+    <div class="final-body" id="final-body">
+
+      <div class="fin-section-title">
+        <svg viewBox="0 0 24 24"><path d="M4 6h16M4 12h16M4 18h10"/></svg>
+        Шпаргалка курса
+      </div>
+
+      <div class="cheat-grid">
+        <div class="cheat-card c1">
+          <div class="cheat-head">
+            <span class="cheat-badge">Гл. 1</span>
+            <span class="cheat-title">Рациональные выражения</span>
+          </div>
+          <ul class="cheat-list">
+            <li>ОДЗ: $Q(x) \ne 0$</li>
+            <li>Сокращение: $\dfrac{AC}{BC} = \dfrac{A}{B}$ — только МНОЖИТЕЛЬ</li>
+            <li>НОЗ — общий знаменатель дробей</li>
+          </ul>
+        </div>
+        <div class="cheat-card c2">
+          <div class="cheat-head">
+            <span class="cheat-badge">Гл. 2</span>
+            <span class="cheat-title">Функции</span>
+          </div>
+          <ul class="cheat-list">
+            <li>$y = f(x)$, $D(f)$, $E(f)$</li>
+            <li>Возр./убыв., нули, экстремумы</li>
+            <li>Чёт./нечёт.: $f(-x) = \pm f(x)$</li>
+            <li>Сдвиги: $y = f(x - a) + b$</li>
+          </ul>
+        </div>
+        <div class="cheat-card c3">
+          <div class="cheat-head">
+            <span class="cheat-badge">Гл. 3</span>
+            <span class="cheat-title">Дробно-рациональные</span>
+          </div>
+          <ul class="cheat-list">
+            <li>$\dfrac{P}{Q} = 0$: $P = 0,\ Q \ne 0$</li>
+            <li>Окружность: $(x-a)^2 + (y-b)^2 = R^2$</li>
+            <li>Метод интервалов: знаки на прямой</li>
+          </ul>
+        </div>
+        <div class="cheat-card c4">
+          <div class="cheat-head">
+            <span class="cheat-badge">Гл. 4</span>
+            <span class="cheat-title">Прогрессии</span>
+          </div>
+          <ul class="cheat-list">
+            <li>Арифм.: $a_n = a_1 + (n-1)d$, $S_n = \dfrac{a_1 + a_n}{2} \cdot n$</li>
+            <li>Геом.: $b_n = b_1 q^{n-1}$, $S_n = \dfrac{b_1(q^n - 1)}{q - 1}$</li>
+            <li>Беск. убыв.: $S = \dfrac{b_1}{1 - q}$ при $|q| &lt; 1$</li>
+          </ul>
+        </div>
+      </div>
+
+      <div class="fin-section-title">
+        <svg viewBox="0 0 24 24"><path d="M14.5 3.5l-5 5L4 4l1.5 6L3 12l5 1 1 5 2.5-2.5 6 1.5-4.5-5.5 5-5"/></svg>
+        7 интегрированных боссов
+      </div>
+
+      <div class="boss-overall-bar">
+        <div class="lab" id="fin-boss-lab">Боссов побеждено: 0 / 7</div>
+        <div class="bar"><div class="fill" id="fin-boss-fill" style="width:0%"></div></div>
+      </div>
+
+      <div id="fin-bosses-container"></div>
+
+      <div class="final-cta" id="final-cta">
+        <div class="final-cta-icon">
+          <svg viewBox="0 0 24 24"><path d="M6 9H4l-1-3h18l-1 3h-2M6 9l1 6h10l1-6M6 9h12"/><path d="M9 21h6M12 15v6"/></svg>
+        </div>
+        <div class="final-cta-txt">
+          <div class="final-cta-title">Магистр алгебры 9 разблокирован!</div>
+          <div class="final-cta-sub">Вы прошли всю итоговую проверку курса. +50 XP, ачивка получена.</div>
+        </div>
+        <a href="/textbooks" class="final-cta-btn">
+          К каталогу учебников
+          <svg viewBox="0 0 24 24"><polyline points="9 18 15 12 9 6"/></svg>
+        </a>
+      </div>
+
+    </div>
+  </section>
+
  <div class="ach-strip" id="ach-strip">
    <div class="ach-icon">
      <svg viewBox="0 0 24 24">
@@ -320,14 +504,298 @@ function renderProgress(children) {
    xpBadge.textContent = xp + ' XP';
  }

-  if (totalRead >= TOTAL) {
+  var mastered = localStorage.getItem(FIN_ACH_KEY) === '1';
+  if (totalRead >= TOTAL || mastered) {
    var strip = document.getElementById('ach-strip');
    var sub   = document.getElementById('ach-sub');
    if (strip) strip.classList.add('lit');
-    if (sub)   sub.textContent = 'Выполнено! Вы прочитали весь курс алгебры 9 класса.';
+    if (sub) {
+      if (mastered) sub.textContent = 'Выполнено! Вы — Магистр алгебры 9.';
+      else          sub.textContent = 'Выполнено! Вы прочитали весь курс алгебры 9 класса.';
+    }
  }
 }

+/* COURSE FINAL — lazy bosses */
+var FIN_BOSS_KEY = 'algebra9_course_bosses';
+var FIN_ACH_KEY  = 'algebra9_course_master';
+
+var FIN_BOSSES = [
+  {
+    n: 1,
+    title: 'Эльдер Метод Интервалов',
+    tag: '§ 3 + § 13',
+    q: 'Решите неравенство $\\dfrac{x^2 - 4}{x + 3} \\le 0$. Сколько <b>целых</b> значений $x \\in [-5;\\,5]$ удовлетворяют ему?',
+    hint: 'Разложите: $x^2 - 4 = (x-2)(x+2)$. Корни числителя $\\pm 2$ (закрашены), корень знаменателя $-3$ (выколота). Метод интервалов на отрезке $[-5;\\,5]$.',
+    ans: 7
+  },
+  {
+    n: 2,
+    title: 'Геометр Прогрессий',
+    tag: '§ 18 + § 7',
+    q: 'Функция $f(n) = 2n - 1$ задаёт последовательность нечётных чисел. Найдите $S_{10}$ — сумму первых 10 её членов.',
+    hint: 'Это арифм. прогрессия: $a_1 = 1,\\ a_{10} = 19$. Формула $S_n = \\dfrac{a_1 + a_n}{2}\\cdot n$.',
+    ans: 100
+  },
+  {
+    n: 3,
+    title: 'Окружность Корней',
+    tag: '§ 3 + § 10',
+    q: 'При каком значении $x$ равны функции $y = \\dfrac{x + 2}{x - 3}$ и $y = \\dfrac{6}{x - 3}$?',
+    hint: 'Знаменатели равны, ОДЗ $x \\ne 3$. Приравняйте числители: $x + 2 = 6$.',
+    ans: 4
+  },
+  {
+    n: 4,
+    title: 'Сдвиг Параболы',
+    tag: '§ 9 + § 10',
+    q: 'Парабола $y = (x - 2)^2 + 3$ пересекается с прямой $y = 4$. Сколько корней у получившегося уравнения?',
+    hint: '$(x - 2)^2 + 3 = 4 \\Rightarrow (x - 2)^2 = 1$. Это квадратное уравнение.',
+    ans: 2
+  },
+  {
+    n: 5,
+    title: 'Беск. Убывающая',
+    tag: '§ 19 + § 1',
+    q: 'Превратите бесконечную периодическую дробь $0{,}(142857)$ в обыкновенную и введите её <b>знаменатель</b> в несократимом виде.',
+    hint: 'Числитель — период 142857, знаменатель — 999999. Сократите: $142857 \\cdot 7 = 999999$.',
+    ans: 7
+  },
+  {
+    n: 6,
+    title: 'Логистика Расстояний',
+    tag: '§ 12 + § 6',
+    q: 'Точки $A(0;\\,0)$ и $B(6;\\,8)$ лежат на окружности с центром $C(3;\\,4)$. Чему равен радиус?',
+    hint: '$R = |CA| = \\sqrt{(3-0)^2 + (4-0)^2}$.',
+    ans: 5
+  },
+  {
+    n: 7,
+    title: 'Магистр Алгебры',
+    tag: 'синтез всех глав',
+    q: 'В арифм. прогрессии $a_1 = 2$, $a_5 = 14$. Найдите знаменатель геом. прогрессии $b_n$, у которой $b_1 = a_1 = 2$, $b_3 = a_5 + 4 = 18$ и $q &gt; 0$.',
+    hint: 'Из $b_3 = b_1\\cdot q^2$ выразите $q^2$ и возьмите положительный корень.',
+    ans: 3
+  }
+];
+
+function loadFinBossState(){
+  try { return JSON.parse(localStorage.getItem(FIN_BOSS_KEY) || '{}') || {}; }
+  catch(e) { return {}; }
+}
+function saveFinBossState(s){
+  try { localStorage.setItem(FIN_BOSS_KEY, JSON.stringify(s)); } catch(e){}
+}
+
+function finRenderKatex(root){
+  if (typeof window.renderMathInElement !== 'function') return;
+  try {
+    window.renderMathInElement(root, {
+      delimiters: [
+        {left: '$$', right: '$$', display: true},
+        {left: '$',  right: '$',  display: false}
+      ],
+      throwOnError: false
+    });
+  } catch(e){}
+}
+
+function updateFinBossBar(state){
+  var won = 0;
+  for (var k in state) if (state[k]) won++;
+  var lab = document.getElementById('fin-boss-lab');
+  var fill = document.getElementById('fin-boss-fill');
+  if (lab) lab.textContent = 'Боссов побеждено: ' + won + ' / ' + FIN_BOSSES.length;
+  if (fill) fill.style.width = Math.round(won * 100 / FIN_BOSSES.length) + '%';
+  return won;
+}
+
+function maybeUnlockMaster(state){
+  if (localStorage.getItem(FIN_ACH_KEY) === '1') return;
+  var won = 0;
+  for (var k in state) if (state[k]) won++;
+  if (won < FIN_BOSSES.length) return;
+
+  localStorage.setItem(FIN_ACH_KEY, '1');
+
+  /* +50 XP */
+  var xp = parseInt(localStorage.getItem('algebra9_xp') || '0', 10) || 0;
+  localStorage.setItem('algebra9_xp', String(xp + 50));
+
+  /* trigger global XP system if available */
+  try {
+    if (window.LS && typeof window.LS.addXp === 'function') {
+      window.LS.addXp(50, 'algebra9-master');
+    } else if (typeof window.addXp === 'function') {
+      window.addXp(50, 'algebra9-master');
+    }
+  } catch(e){}
+
+  /* confetti */
+  try { if (typeof window.confetti === 'function') window.confetti({particleCount: 160, spread: 90, origin: {y: .6}}); } catch(e){}
+
+  /* light up ach-strip */
+  var strip = document.getElementById('ach-strip');
+  var sub   = document.getElementById('ach-sub');
+  if (strip) strip.classList.add('lit');
+  if (sub)   sub.textContent = 'Выполнено! Вы — Магистр алгебры 9.';
+
+  /* show CTA */
+  var cta = document.getElementById('final-cta');
+  if (cta) cta.classList.add('show');
+
+  /* refresh XP badge */
+  var xpBadge = document.getElementById('hero-xp-badge');
+  if (xpBadge) {
+    var newXp = parseInt(localStorage.getItem('algebra9_xp') || '0', 10) || 0;
+    xpBadge.style.display = '';
+    xpBadge.textContent = newXp + ' XP';
+  }
+}
+
+function buildFinBoss(b, state){
+  var solvedClass = state[b.n] ? ' solved' : '';
+  return '<div class="boss-card' + solvedClass + '" id="fin-boss-' + b.n + '-card">'
+    + '<div class="boss-head">'
+    +   '<span class="boss-tag">' + b.tag + '</span>'
+    +   '<span class="boss-title">Босс ' + b.n + '. ' + b.title + '</span>'
+    + '</div>'
+    + '<div class="boss-q" id="fin-boss-' + b.n + '-q">' + b.q + '</div>'
+    + '<div class="boss-row">'
+    +   '<input type="number" class="boss-input" id="fin-boss-' + b.n + '-inp" placeholder="число"' + (state[b.n] ? ' value="' + b.ans + '" disabled' : '') + '>'
+    +   '<button class="boss-btn primary" id="fin-boss-' + b.n + '-go"' + (state[b.n] ? ' disabled' : '') + '>Атаковать</button>'
+    +   '<button class="boss-btn" id="fin-boss-' + b.n + '-hint">Подсказка</button>'
+    + '</div>'
+    + '<div class="boss-hint-txt" id="fin-boss-' + b.n + '-hinttxt">' + b.hint + '</div>'
+    + '<div class="boss-fb' + (state[b.n] ? ' ok' : '') + '" id="fin-boss-' + b.n + '-fb">' + (state[b.n] ? 'Победа! +15 XP. Босс уже повержен.' : '') + '</div>'
+  + '</div>';
+}
+
+function bindFinBoss(b){
+  var state = loadFinBossState();
+  var goBtn   = document.getElementById('fin-boss-' + b.n + '-go');
+  var hintBtn = document.getElementById('fin-boss-' + b.n + '-hint');
+  var inp     = document.getElementById('fin-boss-' + b.n + '-inp');
+  var fb      = document.getElementById('fin-boss-' + b.n + '-fb');
+  var hintTx  = document.getElementById('fin-boss-' + b.n + '-hinttxt');
+  var card    = document.getElementById('fin-boss-' + b.n + '-card');
+  if (!goBtn) return;
+
+  if (hintBtn) hintBtn.addEventListener('click', function(){
+    if (hintTx) hintTx.classList.toggle('show');
+  });
+
+  if (state[b.n]) return; /* already solved */
+
+  goBtn.addEventListener('click', function(){
+    var v = parseFloat((inp.value || '').replace(',', '.'));
+    if (isNaN(v)) {
+      fb.className = 'boss-fb fail';
+      fb.textContent = 'Введите число.';
+      return;
+    }
+    if (Math.abs(v - b.ans) < 1e-9) {
+      fb.className = 'boss-fb ok';
+      fb.textContent = 'Победа! +15 XP. Босс повержен.';
+      card.classList.add('solved');
+      goBtn.disabled = true;
+      inp.disabled = true;
+
+      var s = loadFinBossState();
+      if (!s[b.n]) {
+        s[b.n] = true;
+        saveFinBossState(s);
+
+        /* +15 XP */
+        var xp = parseInt(localStorage.getItem('algebra9_xp') || '0', 10) || 0;
+        localStorage.setItem('algebra9_xp', String(xp + 15));
+        try {
+          if (window.LS && typeof window.LS.addXp === 'function') window.LS.addXp(15, 'fin-boss-' + b.n);
+          else if (typeof window.addXp === 'function') window.addXp(15, 'fin-boss-' + b.n);
+        } catch(e){}
+
+        var xpBadge = document.getElementById('hero-xp-badge');
+        if (xpBadge) {
+          var nXp = parseInt(localStorage.getItem('algebra9_xp') || '0', 10) || 0;
+          xpBadge.style.display = '';
+          xpBadge.textContent = nXp + ' XP';
+        }
+
+        updateFinBossBar(s);
+        maybeUnlockMaster(s);
+      }
+    } else {
+      fb.className = 'boss-fb fail';
+      fb.textContent = 'Не то. Перепроверь решение и попробуй снова.';
+    }
+  });
+
+  inp.addEventListener('keydown', function(e){
+    if (e.key === 'Enter') { e.preventDefault(); goBtn.click(); }
+  });
+}
+
+var FIN_BOSSES_RENDERED = false;
+function renderFinBosses(){
+  if (FIN_BOSSES_RENDERED) return;
+  var cont = document.getElementById('fin-bosses-container');
+  if (!cont) return;
+  var state = loadFinBossState();
+  var html = '';
+  for (var i = 0; i < FIN_BOSSES.length; i++) html += buildFinBoss(FIN_BOSSES[i], state);
+  cont.innerHTML = html;
+  for (var j = 0; j < FIN_BOSSES.length; j++) bindFinBoss(FIN_BOSSES[j]);
+
+  var wrap = document.getElementById('course-final');
+  finRenderKatex(wrap);
+
+  updateFinBossBar(state);
+
+  /* if already mastered: show CTA */
+  if (localStorage.getItem(FIN_ACH_KEY) === '1') {
+    var cta = document.getElementById('final-cta');
+    if (cta) cta.classList.add('show');
+    var strip = document.getElementById('ach-strip');
+    var sub   = document.getElementById('ach-sub');
+    if (strip) strip.classList.add('lit');
+    if (sub)   sub.textContent = 'Выполнено! Вы — Магистр алгебры 9.';
+  }
+
+  FIN_BOSSES_RENDERED = true;
+}
+
+(function bindFinalAccordion(){
+  var head = document.getElementById('final-head');
+  var wrap = document.getElementById('course-final');
+  if (!head || !wrap) return;
+
+  function toggle(){
+    var willOpen = !wrap.classList.contains('open');
+    wrap.classList.toggle('open');
+    head.setAttribute('aria-expanded', willOpen ? 'true' : 'false');
+    if (willOpen) {
+      renderFinBosses();
+      /* always re-render cheat-sheet KaTeX on first open */
+      finRenderKatex(wrap);
+    }
+  }
+
+  head.addEventListener('click', toggle);
+  head.addEventListener('keydown', function(e){
+    if (e.key === 'Enter' || e.key === ' ') { e.preventDefault(); toggle(); }
+  });
+})();
+
+/* sync ach-strip + CTA on load if already mastered */
+(function syncMasterOnLoad(){
+  if (localStorage.getItem(FIN_ACH_KEY) === '1') {
+    var strip = document.getElementById('ach-strip');
+    var sub   = document.getElementById('ach-sub');
+    if (strip) strip.classList.add('lit');
+    if (sub)   sub.textContent = 'Выполнено! Вы — Магистр алгебры 9.';
+  }
+})();
+
 function loadProgress() {
  if (typeof window.LS === 'undefined' || typeof window.LS.api !== 'function') {
    renderProgress([]);