/* Sudoku V1 shared styles */
:root{--bg:#f7f8fa;--surface:#fff;--text:#18212b;--muted:#65717e;--border:#d8dee5;--accent:#315c8c;--accent-dark:#24476d;--soft:#edf3f9;--success:#24734b;--danger:#b33a3a;--max:1100px}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:var(--text);background:var(--bg);line-height:1.6}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}.container{width:min(var(--max),calc(100% - 32px));margin-inline:auto}.site-header{background:var(--surface);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:20}.header-inner{min-height:64px;display:flex;align-items:center;justify-content:space-between;gap:24px}.brand{font-weight:800;font-size:1.35rem;color:var(--text)}.brand:hover{text-decoration:none}.site-header nav,.site-footer nav{display:flex;gap:20px;flex-wrap:wrap}.site-header nav a{color:var(--muted);font-size:.94rem}.hero{padding:64px 0 56px;text-align:center;background:linear-gradient(180deg,#fff 0%,#f7f8fa 100%)}.eyebrow{text-transform:uppercase;letter-spacing:.12em;font-size:.76rem;font-weight:800;color:var(--accent);margin:0 0 8px}.hero h1,.game-page h1{font-size:clamp(2.1rem,5vw,3.5rem);line-height:1.1;margin:0 0 14px}.hero-copy{max-width:680px;margin:0 auto 32px;color:var(--muted);font-size:1.08rem}.difficulty-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;max-width:900px;margin:auto}.difficulty-card{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:22px;text-align:left;display:flex;flex-direction:column;gap:4px;transition:transform .15s,box-shadow .15s}.difficulty-card:hover{transform:translateY(-2px);text-decoration:none;box-shadow:0 8px 24px #1b2a3a12}.difficulty-card strong{font-size:1.15rem;color:var(--text)}.difficulty-card span{font-size:.9rem;color:var(--muted)}.difficulty-card.easy{border-top:4px solid #4b8b65}.difficulty-card.medium{border-top:4px solid #5a7da3}.difficulty-card.hard{border-top:4px solid #a87845}.difficulty-card.expert{border-top:4px solid #9a5151}.ad-slot{min-height:90px;display:flex;align-items:center;justify-content:center;color:#8a939d;font-size:.7rem;letter-spacing:.08em;text-transform:uppercase}.ad-slot span{border:1px dashed #cdd3d9;padding:8px 24px}.content-section{padding:58px 0;background:#fff}.content-section.light{background:#f1f4f7}.split-section{display:grid;grid-template-columns:1.4fr .8fr;gap:48px;align-items:center}.content-section h2{font-size:2rem;line-height:1.2;margin:0 0 14px}.button,.primary{display:inline-flex;align-items:center;justify-content:center;background:var(--accent);color:#fff;border:0;border-radius:9px;padding:11px 18px;font-weight:700;cursor:pointer}.button:hover,.primary:hover{background:var(--accent-dark);text-decoration:none}.secondary-button{background:#fff;color:var(--text);border:1px solid var(--border)}.secondary-button:hover{background:#f1f4f7}.button:disabled{opacity:.5;cursor:not-allowed}.feature-box,.info-card,.article-card{background:#fff;border:1px solid var(--border);border-radius:14px;padding:24px}.feature-box{display:flex;flex-direction:column;gap:8px;text-align:center}.feature-icon{font-size:2.2rem;font-weight:800;color:var(--accent)}.article-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.article-card{color:var(--text)}.article-card:hover{text-decoration:none;box-shadow:0 8px 24px #1b2a3a10}.article-card h3{margin:0 0 6px}.article-card p{margin:0;color:var(--muted)}.prose{max-width:850px}.prose p{color:#4d5965}.game-page{padding:42px 0}.game-layout{display:grid;grid-template-columns:minmax(0,720px) 280px;gap:28px;align-items:start}.game-intro{color:var(--muted);margin-top:-4px}.game-card{background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:20px;box-shadow:0 8px 30px #18212b0b}.game-toolbar{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px}.pill{background:var(--soft);color:var(--accent);border-radius:999px;padding:4px 12px;font-size:.8rem;font-weight:800}.timer{font-variant-numeric:tabular-nums;font-weight:700}.sudoku-board{width:min(100%,540px);aspect-ratio:1;margin:0 auto 18px;display:grid;grid-template-columns:repeat(9,1fr);border:3px solid #263544;background:#fff}.cell{appearance:none;border:0;border-right:1px solid #aeb8c2;border-bottom:1px solid #aeb8c2;background:#fff;color:var(--accent);font-size:clamp(1.15rem,4vw,1.65rem);font-weight:650;display:flex;align-items:center;justify-content:center;position:relative;cursor:pointer;padding:0}.cell:nth-child(9n){border-right:0}.cell:nth-child(n+73){border-bottom:0}.cell.box-right{border-right:2px solid #263544}.cell.box-bottom{border-bottom:2px solid #263544}.cell.given{color:#1e2832;font-weight:800;background:#f5f7f9;cursor:default}.cell.selected{background:#dfeaf5}.cell.related{background:#f1f6fa}.cell.same-number{background:#e8f0f8}.cell.error{color:var(--danger);background:#fbeeee}.cell.notes{font-size:.68rem}.notes-grid{display:grid;grid-template-columns:repeat(3,1fr);width:100%;height:100%;padding:3px;line-height:1.1}.notes-grid span{display:flex;align-items:center;justify-content:center}.number-pad{width:min(100%,540px);margin:auto;display:grid;grid-template-columns:repeat(5,1fr);gap:8px}.number-pad button,.game-actions button{min-height:44px;border:1px solid var(--border);border-radius:9px;background:#fff;font:inherit;font-weight:700;cursor:pointer;color:var(--text)}.number-pad button:hover,.game-actions button:hover{background:#f1f4f7}.game-actions{width:min(100%,540px);margin:14px auto 0;display:grid;grid-template-columns:repeat(5,1fr);gap:8px}.game-actions .primary{color:#fff;background:var(--accent)}.game-message{text-align:center;min-height:26px;margin:14px 0 0;font-weight:650}.game-message.success{color:var(--success)}.game-message.error{color:var(--danger)}.ad-sidebar{min-height:280px;background:#fff;border:1px solid var(--border);border-radius:12px}.info-card{margin-top:20px}.info-card h2{font-size:1.2rem;margin-top:0}.print-controls{display:flex;align-items:end;gap:12px;flex-wrap:wrap;margin:28px 0 12px;padding:20px;background:#f1f4f7;border:1px solid var(--border);border-radius:14px}.form-field{display:flex;flex-direction:column;gap:5px}.form-field label{font-size:.85rem;font-weight:700}.form-field select{min-height:44px;border:1px solid var(--border);border-radius:8px;background:#fff;padding:0 12px;font:inherit;color:var(--text)}.checkbox-field{justify-content:center;min-height:44px}.checkbox-field label{display:flex;align-items:center;gap:8px;font-weight:600}.checkbox-field input{width:18px;height:18px}.print-status{font-size:.9rem;color:var(--muted);margin:8px 0}.print-preview-section{padding:36px 0;background:#e9edf1}.print-preview{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:24px}.print-page{background:#fff;min-height:470px;padding:28px;display:flex;flex-direction:column;align-items:center;justify-content:flex-start;box-shadow:0 3px 14px #18212b12}.print-page h2{margin:0;font-size:1.25rem}.print-meta{margin:2px 0 20px;color:var(--muted);font-size:.85rem}.print-grid{width:min(100%,360px);aspect-ratio:1;display:grid;grid-template-columns:repeat(9,1fr);border:2px solid #202a33}.print-cell{display:flex;align-items:center;justify-content:center;border-right:1px solid #9ba5ae;border-bottom:1px solid #9ba5ae;font-size:1.15rem;font-weight:600}.print-cell:nth-child(9n){border-right:0}.print-cell:nth-child(n+73){border-bottom:0}.print-cell.print-box-right{border-right:2px solid #202a33}.print-cell.print-box-bottom{border-bottom:2px solid #202a33}.print-page-footer{margin-top:auto;padding-top:20px;font-size:.68rem;color:#8a939d}.site-footer{background:#202a33;color:#d8dee5;padding:28px 0;margin-top:20px}.footer-inner{display:flex;justify-content:space-between;gap:20px;font-size:.88rem}.site-footer a{color:#d8dee5}@media(max-width:800px){.difficulty-grid{grid-template-columns:repeat(2,1fr)}.game-layout,.split-section{grid-template-columns:1fr}.game-sidebar{display:none}.article-grid{grid-template-columns:1fr}.hero{padding:48px 0}.header-inner{align-items:flex-start;padding:14px 0}.site-header nav{gap:12px;font-size:.85rem}.game-card{padding:12px}.game-actions{grid-template-columns:repeat(3,1fr)}.game-actions .primary{grid-column:span 3}.number-pad{grid-template-columns:repeat(5,1fr)}.print-preview{grid-template-columns:1fr}.print-controls{align-items:stretch}.print-controls .button{flex:1;min-width:140px}}@media(max-width:480px){.container{width:min(var(--max),calc(100% - 20px))}.difficulty-grid{grid-template-columns:1fr}.hero h1{font-size:2.25rem}.site-header nav a:nth-child(2){display:none}.game-page{padding:28px 0}.number-pad{gap:5px}.number-pad button{min-height:42px}.game-actions{gap:5px}.game-actions button{min-height:42px}.cell{font-size:1.15rem}.print-page{padding:20px;min-height:400px}}
@media print{body{background:#fff}.site-header,.site-footer,.print-controls,.print-status,.ad-slot,.content-section.light,.print-preview-section>.container:before{display:none!important}.print-preview-section{padding:0;background:#fff}.print-preview{display:block}.print-page{display:flex;min-height:100vh;width:100%;padding:20mm 15mm;box-shadow:none;page-break-after:always;break-after:page}.print-page:last-child{page-break-after:auto;break-after:auto}.print-page h2{font-size:18pt}.print-meta{font-size:10pt}.print-grid{width:150mm;max-width:100%;border-width:2px}.print-cell{font-size:18pt}.print-page-footer{font-size:8pt;color:#666}@page{size:letter portrait;margin:0}}