SEO 10x upgrade for 6 cornerstone games (Chess, Solitaire, Sudoku, 2048, Minesweeper, Mahjong)

Each cornerstone now ships:
  - BreadcrumbList JSON-LD (renders as breadcrumb in SERPs)
  - FAQPage JSON-LD with 5 substantive game-specific questions
  - Quick visible content section below the game UI containing
    "About", "How to play", a reference table specific to that game
    (chess piece movements, sudoku techniques, 2048 tile values,
    minesweeper number colors + grid presets, mahjong tile categories,
    klondike layout), 5 visible <details> FAQs matching the schema,
    and 4 cross-links to other games on the hub.
  - Existing VideoGame schema kept intact.

nav.js extended with shared `.seo-content` styles so the per-page
markup is just the <section>, no duplicated CSS block.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: mf4633

2048.html

@@ -27,6 +27,8 @@
   "offers": { "@type": "Offer", "price": "0", "priceCurrency": "USD" }
 }
 </script>
+<script type="application/ld+json">{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Board Gaming Hub","item":"https://boardgaminghub.com/"},{"@type":"ListItem","position":2,"name":"Puzzles & Classics","item":"https://boardgaminghub.com/#puzzles"},{"@type":"ListItem","position":3,"name":"2048","item":"https://boardgaminghub.com/2048.html"}]}</script>
+<script type="application/ld+json">{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"How do you play 2048?","acceptedAnswer":{"@type":"Answer","text":"Use arrow keys (or swipe on touch devices) to slide every tile in one direction. When two adjacent tiles with the same number meet, they merge into a single tile of double value. After every move a new 2 (90% of the time) or 4 (10%) appears in a random empty cell. The game ends when no moves are possible."}},{"@type":"Question","name":"What's the best 2048 strategy?","acceptedAnswer":{"@type":"Answer","text":"Pin the largest tile in one corner (most players use bottom-right) and never move it. Build a snake-pattern descending row that feeds into that corner: e.g., bottom row left-to-right increasing, second row right-to-left, etc. Avoid pressing the direction that would shift the corner — typically Up if your corner is bottom-right. With perfect play this strategy reaches 2048 reliably and 4096 often."}},{"@type":"Question","name":"What's the highest tile possible in 2048?","acceptedAnswer":{"@type":"Answer","text":"Theoretical maximum is 131,072 (2^17), achieved by merging tiles up to that value on a 4×4 grid. Practically the cap is far lower because once tiles fill the board and the highest tile cannot be merged, you lose. The 2048 tile (the win condition) is reached by ~5–10% of casual players; 4096 by perhaps 1%."}},{"@type":"Question","name":"How is the score calculated?","acceptedAnswer":{"@type":"Answer","text":"Each merge adds the value of the new tile to your score. Two 2s → 4 (+4). Two 8s → 16 (+16). Two 1024s → 2048 (+2048). Total score after reaching 2048 from a fresh game is around 20,000; reaching 4096 around 50,000."}},{"@type":"Question","name":"Why does the same tile keep spawning in the wrong place?","acceptedAnswer":{"@type":"Answer","text":"Spawn position is uniformly random among empty cells. It feels biased after a streak but isn't. The 2 vs 4 spawn is weighted 90/10 — getting a 4 spawn is meaningful because it skips a doubling step (and slightly accelerates filling the board)."}}]}</script>
 <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-2835365593874464" crossorigin="anonymous"></script>
 <style>
   * { box-sizing: border-box; }
@@ -236,6 +238,46 @@ <h2>Strategy</h2>
 })();
 </script>
 <script src="/analytics.js"></script>
+<section class="seo-content">
+  <h2>About 2048</h2>
+  <p>2048 is a single-player tile-merging puzzle on a 4×4 grid, designed by Italian programmer Gabriele Cirulli in 2014 and released as open-source the same week. The goal is to combine matching numbered tiles by sliding them, doubling each merge until you create a tile valued <strong>2048</strong>. Game ends when no further moves are possible.</p>
+
+  <h3>How to play</h3>
+  <p>Press an arrow key (or swipe on touch) to slide every tile in that direction. Two adjacent tiles with the same number merge into one of double value. After every move, a new <strong>2</strong> (90% of the time) or <strong>4</strong> (10%) appears in a random empty cell. The board fills as you fail to merge; the game ends when no slide produces movement or merge.</p>
+
+  <h3>Tile values &amp; scoring</h3>
+  <table>
+    <thead><tr><th>Tile</th><th>Source</th><th class="num">Score on merge</th></tr></thead>
+    <tbody>
+      <tr><td>2</td><td>Spawn (90%)</td><td class="num">—</td></tr>
+      <tr><td>4</td><td>Spawn (10%) or two 2s</td><td class="num">+4</td></tr>
+      <tr><td>8</td><td>Two 4s</td><td class="num">+8</td></tr>
+      <tr><td>16, 32, 64, 128</td><td>Two of half-value</td><td class="num">+value</td></tr>
+      <tr><td>256, 512, 1024</td><td>Two of half-value</td><td class="num">+value</td></tr>
+      <tr><td><strong>2048</strong> (win)</td><td>Two 1024s</td><td class="num"><strong>+2048</strong></td></tr>
+      <tr><td>4096, 8192…</td><td>Continue past the win</td><td class="num">+value</td></tr>
+    </tbody>
+  </table>
+
+  <h3>Strategy: corner + snake</h3>
+  <p>The dominant strategy is the <strong>corner snake</strong>: pin your largest tile in one corner (most use bottom-right) and never move it. Build a descending zig-zag from that corner: bottom row right-to-left increasing, second row left-to-right, etc. Avoid pressing the direction that would shift the corner away — typically Up if your corner is bottom-right. With perfect play this strategy reaches 2048 reliably and 4096 often.</p>
+
+  <h3>Frequently asked questions</h3>
+  <details><summary>How do you play 2048?</summary><p>Arrow keys or swipe to slide all tiles in one direction. Adjacent matching tiles merge into one of double value. A new 2 or 4 spawns each move. Reach 2048 to win; keep going for higher tiles.</p></details>
+  <details><summary>Best strategy?</summary><p>Pin the largest tile in a corner; never move it. Build a snake-pattern row that feeds into it. Avoid pressing the direction that would shift the corner.</p></details>
+  <details><summary>Highest tile possible?</summary><p>Theoretically 131,072 (2¹⁷). Practically the game ends earlier when the board fills. The 2048 win tile is reached by ~5–10% of casual players; 4096 by ~1%.</p></details>
+  <details><summary>How is the score calculated?</summary><p>Each merge adds the value of the new tile to your score. Reaching 2048 from a fresh game scores ~20,000; reaching 4096 ~50,000.</p></details>
+  <details><summary>Why does the same spot keep spawning?</summary><p>Spawn position is uniformly random among empty cells. It feels biased after a streak but isn't. The 2-vs-4 spawn is weighted 90/10.</p></details>
+
+  <h3>Related games</h3>
+  <ul>
+    <li><a href="Sudoku.html">Sudoku</a> — number puzzle, pure logic.</li>
+    <li><a href="Solitaire.html">Solitaire</a> — solo card game, similar pace.</li>
+    <li><a href="Minesweeper.html">Minesweeper</a> — solo logic puzzle, deduction-driven.</li>
+    <li><a href="Mahjong.html">Mahjong Solitaire</a> — solo pattern matching.</li>
+  </ul>
+</section>
+
 <section style="max-width:900px;margin:60px auto 40px;padding:0 20px;font-family:Georgia,'Times New Roman',serif;color:#d8d0c0;">
   <h2 style="color:#f0d89c;letter-spacing:4px;font-size:1.0em;text-transform:uppercase;border-bottom:1px solid #2a3540;padding-bottom:8px;margin-bottom:16px;">Discussion</h2>
   <p style="color:#8098a8;font-size:0.9em;margin-bottom:18px;line-height:1.5;">Sign in with GitHub to share strategies, ask questions, or report a bug.</p>

Chess.html

@@ -34,6 +34,8 @@
     "applicationCategory": "Game", "operatingSystem": "Any",
     "offers": { "@type": "Offer", "price": "0", "priceCurrency": "USD" } }
   </script>
+  <script type="application/ld+json">{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Board Gaming Hub","item":"https://boardgaminghub.com/"},{"@type":"ListItem","position":2,"name":"Puzzles & Classics","item":"https://boardgaminghub.com/#puzzles"},{"@type":"ListItem","position":3,"name":"Chess","item":"https://boardgaminghub.com/Chess.html"}]}</script>
+  <script type="application/ld+json">{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"How does each chess piece move?","acceptedAnswer":{"@type":"Answer","text":"King: 1 square in any direction (also castling). Queen: any distance along ranks, files, or diagonals. Rook: any distance along ranks or files. Bishop: any distance along diagonals. Knight: L-shape (2+1), the only piece that jumps over others. Pawn: forward 1 square (or 2 from its starting rank), captures diagonally, promotes on reaching rank 8."}},{"@type":"Question","name":"What is castling and when can I do it?","acceptedAnswer":{"@type":"Answer","text":"Castling is a special two-piece king-and-rook move performed in one turn. Conditions: the king and the chosen rook have not yet moved; no pieces sit between them; the king is not currently in check; and the king does not pass through or land on a square attacked by an enemy piece. Kingside castling places the king on g-file, rook on f-file. Queenside places the king on c-file, rook on d-file."}},{"@type":"Question","name":"What is en passant?","acceptedAnswer":{"@type":"Answer","text":"When an enemy pawn advances two squares from its starting rank and ends beside one of your pawns, you may capture it on your very next move as if it had moved only one square. The capturing pawn moves diagonally to the square the enemy pawn passed over. Must be played on the immediate next turn or the right is lost."}},{"@type":"Question","name":"What's the difference between checkmate and stalemate?","acceptedAnswer":{"@type":"Answer","text":"Checkmate: the side to move is in check with no legal escape — game ends, checkmating side wins. Stalemate: the side to move is NOT in check but has no legal moves at all — game ends in a draw. Stalemating a winning position is a common way for beginners to throw away material advantage."}},{"@type":"Question","name":"What's a good chess opening for beginners?","acceptedAnswer":{"@type":"Answer","text":"For White, 1.e4 leads to open tactical games — try the Italian Game (1.e4 e5 2.Nf3 Nc6 3.Bc4) or the Ruy Lopez (3.Bb5). For Black against 1.e4, the Caro-Kann (1...c6) and French (1...e6) are solid. Against 1.d4, the Slav (1...d5 2.c4 c6) and King's Indian (1...Nf6 2.c4 g6) are widely played. The principles — control the center, develop minor pieces before queens or rooks, castle early, connect rooks — matter more than memorized lines below ~1500 Elo."}},{"@type":"Question","name":"What is the 50-move rule?","acceptedAnswer":{"@type":"Answer","text":"If 50 consecutive moves are made by both sides with no capture and no pawn move, either player may claim a draw. The counter resets on every capture or pawn push. The threefold-repetition rule is similar: if the same position (with the same player to move and same castling/en-passant rights) occurs three times, either side may claim a draw."}}]}</script>
   <link rel="icon" href="data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 100 100'><text y='.9em' font-size='90'>♟️</text></svg>">
   <style>
     * { box-sizing: border-box; margin: 0; padding: 0; }
@@ -1416,6 +1418,71 @@ <h2 id="game-over-title">Game Over</h2>
 </script>
 
 <script src="/analytics.js"></script>
+
+<section class="seo-content">
+  <h2>About Chess</h2>
+  <p>Chess is a two-player abstract strategy game played on an 8×8 board with 32 pieces (16 per side). The objective is <strong>checkmate</strong>: deliver an attack on the opposing king from which there is no legal escape. Recorded in essentially its modern form since the 15th century, chess is the most-played and most-studied board game in the world.</p>
+
+  <h3>How to play</h3>
+  <p>Each side starts with 1 king, 1 queen, 2 rooks, 2 bishops, 2 knights, and 8 pawns. White moves first; players alternate one move per turn. A move must either place the king out of check, prevent check, or simply develop a piece toward the opposing position. Three special moves — <strong>castling</strong>, <strong>en passant</strong>, and <strong>pawn promotion</strong> — round out the standard rules.</p>
+
+  <h3>Piece movement reference</h3>
+  <table>
+    <thead><tr><th>Piece</th><th>Movement</th><th class="num">Approx. value</th></tr></thead>
+    <tbody>
+      <tr><td>King ♔</td><td>1 square in any direction; also castling, once per game</td><td class="num">—</td></tr>
+      <tr><td>Queen ♕</td><td>Any distance along ranks, files, or diagonals</td><td class="num">9</td></tr>
+      <tr><td>Rook ♖</td><td>Any distance along ranks or files</td><td class="num">5</td></tr>
+      <tr><td>Bishop ♗</td><td>Any distance along diagonals</td><td class="num">3</td></tr>
+      <tr><td>Knight ♘</td><td>L-shape (2+1); the only piece that jumps over others</td><td class="num">3</td></tr>
+      <tr><td>Pawn ♙</td><td>Forward 1 (or 2 from starting rank); captures diagonally; promotes on rank 8</td><td class="num">1</td></tr>
+    </tbody>
+  </table>
+
+  <h3>How games end</h3>
+  <ul>
+    <li><strong>Checkmate</strong> — king in check with no legal escape (win for the checkmating side).</li>
+    <li><strong>Stalemate</strong> — side to move has no legal moves but is NOT in check (draw).</li>
+    <li><strong>50-move rule</strong> — 50 consecutive moves with no capture and no pawn move (draw can be claimed).</li>
+    <li><strong>Threefold repetition</strong> — the same position occurs three times with the same player to move (draw can be claimed).</li>
+    <li><strong>Insufficient material</strong> — neither side has enough pieces to force checkmate (automatic draw).</li>
+  </ul>
+
+  <h3>Frequently asked questions</h3>
+  <details>
+    <summary>How does each chess piece move?</summary>
+    <p>King: 1 square in any direction (also castling). Queen: any distance along ranks, files, or diagonals. Rook: any distance along ranks or files. Bishop: any distance along diagonals. Knight: L-shape (2+1), the only piece that jumps. Pawn: forward 1 (or 2 from starting rank), captures diagonally, promotes on rank 8.</p>
+  </details>
+  <details>
+    <summary>What is castling and when can I do it?</summary>
+    <p>A special king + rook move done on one turn. Conditions: neither piece has moved; no pieces between them; the king is not in check; the king does not pass through or land on a square under attack. Kingside puts the king on g-file and the rook on f-file; queenside puts the king on c-file and rook on d-file.</p>
+  </details>
+  <details>
+    <summary>What is en passant?</summary>
+    <p>When an enemy pawn advances two squares from its starting rank and ends beside your pawn, you may capture it as if it had moved only one square — but only on your very next move.</p>
+  </details>
+  <details>
+    <summary>Checkmate vs stalemate?</summary>
+    <p>Checkmate ends the game with a win for the checkmating side. Stalemate — no legal moves but the king is not in check — ends the game in a draw. A common way beginners throw away winning positions.</p>
+  </details>
+  <details>
+    <summary>What's a good opening for beginners?</summary>
+    <p>For White, 1.e4 leads to open tactical games — try the Italian Game (1.e4 e5 2.Nf3 Nc6 3.Bc4) or Ruy Lopez (3.Bb5). For Black against 1.e4: Caro-Kann (1...c6) or French (1...e6) are solid. The principles — control the center, develop minor pieces, castle early, connect rooks — matter more than memorized lines below ~1500 Elo.</p>
+  </details>
+  <details>
+    <summary>What's the 50-move rule?</summary>
+    <p>If 50 consecutive moves go by with no capture and no pawn move, either side may claim a draw. The counter resets on every capture or pawn push.</p>
+  </details>
+
+  <h3>Related games</h3>
+  <ul>
+    <li><a href="Go.html">Go</a> — territory-and-influence strategy on a 19×19 board.</li>
+    <li><a href="Othello.html">Othello</a> — capture-by-flanking, dramatically shorter games than chess.</li>
+    <li><a href="Backgammon.html">Backgammon</a> — race-and-tactics, dice-driven counterpart to chess.</li>
+    <li><a href="Mancala.html">Mancala</a> — ancient count-and-capture, fast learning curve.</li>
+  </ul>
+</section>
+
 <section style="max-width:900px;margin:60px auto 40px;padding:0 20px;font-family:Georgia,'Times New Roman',serif;color:#d8d0c0;">
   <h2 style="color:#f0d89c;letter-spacing:4px;font-size:1.0em;text-transform:uppercase;border-bottom:1px solid #2a3540;padding-bottom:8px;margin-bottom:16px;">Discussion</h2>
   <p style="color:#8098a8;font-size:0.9em;margin-bottom:18px;line-height:1.5;">Sign in with GitHub to share strategies, ask questions, or report a bug.</p>