body {
    --page-bg: #ffffff;
    --text: #000000;
    --surface: #ffffff;
    --surface-muted: #f5f5f5;
    --border: #000000;
    --muted: #666666;
    --overlay: rgba(0, 0, 0, 0.65);
    font-family: Helvetica, Arial, sans-serif;
    text-align: center;
    margin: 20px;
    padding-bottom: 64px;
    background: var(--page-bg);
    color: var(--text);
}
body.dark-theme { --page-bg:#111111; --text:#eeeeee; --surface:#1d1d1d; --surface-muted:#292929; --border:#777777; --muted:#b7b7b7; --overlay:rgba(0,0,0,.78); }
body.rules-open{overflow:hidden;overscroll-behavior:none}
h1{font-size:38px;margin-bottom:5px}h2{font-weight:normal;margin-top:0}#timer{font-size:28px;margin:20px}
.shareModal{display:none;position:fixed;inset:0;z-index:1000}.shareModal.open{display:flex;align-items:center;justify-content:center}.shareOverlay{position:absolute;inset:0;background:var(--overlay)}.shareBox{position:relative;z-index:1;width:min(90%,420px);padding:30px;background:var(--surface);color:var(--text);border-radius:20px;text-align:center;box-shadow:0 20px 60px rgba(0,0,0,.35)}.shareClose{position:absolute;top:10px;right:15px;border:none;background:transparent;color:inherit;font-size:32px;cursor:pointer}.shareGraphic{padding:25px;border-radius:15px;background:var(--surface-muted)}.shareBrand{font-size:28px;font-weight:bold;letter-spacing:3px;margin:15px 0}.shareStat{margin:15px 0}.shareStat strong{display:block;font-size:32px}.shareStat span{color:var(--muted)}.shareButtons{display:flex;gap:10px;justify-content:center;margin-top:20px;flex-wrap:wrap}.shareButtons button{padding:12px 18px;border:1px solid var(--border);border-radius:10px;cursor:pointer;font-size:16px;min-width:92px}
#grid{display:grid;grid-template-columns:repeat(5,minmax(45px,60px));gap:2px;justify-content:center;width:min(90%,300px);max-width:90%;box-sizing:border-box;margin:25px auto}#grid[style*="repeat(5"]{width:min(90%,300px);grid-template-columns:repeat(5,minmax(0,1fr))!important}#grid[style*="repeat(7"]{width:min(90%,420px);grid-template-columns:repeat(7,minmax(0,1fr))!important}#grid[style*="repeat(9"]{width:min(90%,504px);grid-template-columns:repeat(9,minmax(0,1fr))!important}.cell{aspect-ratio:1;border:1px solid var(--border);display:flex;align-items:center;justify-content:center;font-size:20px;cursor:pointer;user-select:none;touch-action:none}.cell.clue{font-weight:bold}.cell.active{background:#000;color:#fff}.dark-theme .cell.active,.dark-theme .cell.black{background:#000;color:#fff}.cell.black{background:#000;border-color:#000;cursor:default}#message{min-height:30px;margin:15px;font-size:18px}button{padding:10px 25px;font-size:16px;background:var(--surface);color:var(--text);border:1px solid var(--border);cursor:pointer}button:disabled{opacity:.5;cursor:not-allowed}.pdf-date-nav{display:flex;align-items:center;justify-content:center;gap:20px;margin:20px 0}.pdf-date-nav button{padding:10px 18px;cursor:pointer}#currentDate{min-width:180px;text-align:center;font-weight:bold}.pdf-action{text-align:center;margin-top:15px}.pdf-action button{padding:12px 24px;cursor:pointer}.date-navigation{display:flex;align-items:stretch;justify-content:center;gap:12px;margin:10px 0}.date-navigation button{width:64px;min-width:64px;height:56px;padding:0;font-size:44px;line-height:1;display:inline-flex;align-items:center;justify-content:center}.date-navigation #currentDate{min-width:180px;min-height:56px;display:inline-flex;align-items:center;justify-content:center}.shareBox{max-height:92vh;overflow-y:auto}.shareBadgeImage{display:block;width:min(100%,360px);aspect-ratio:5/7;height:auto;object-fit:contain;margin:0 auto 16px;border:1px solid var(--border);border-radius:8px}.shareStatsRow{display:flex;justify-content:space-around;gap:10px;margin:12px 0}.shareStatsRow .shareStat{flex:1;margin:0}.shareStatsRow .shareStat strong{font-size:24px}.shareDate{margin-top:12px;color:var(--muted)}
.rulesModal{display:none!important;position:fixed!important;inset:0!important;width:100vw;height:100vh;height:100dvh;z-index:1100;box-sizing:border-box;align-items:center;justify-content:center;padding:12px}.rulesModal.open{display:flex!important}.rulesModal[hidden]{display:none!important}.rulesOverlay{position:absolute;inset:0;width:100%;height:100%;background:var(--overlay);touch-action:none}.rulesBox{position:relative;z-index:1;box-sizing:border-box;width:min(520px,calc(100vw - 24px));max-width:520px;max-height:min(700px,calc(100vh - 24px));max-height:min(700px,calc(100dvh - 24px));overflow-x:hidden;overflow-y:auto;-webkit-overflow-scrolling:touch;overscroll-behavior:contain;padding:46px 24px 24px;margin:0;background:var(--surface);color:var(--text);border-radius:16px;text-align:left;box-shadow:0 20px 60px rgba(0,0,0,.35)}.rulesBox h2{text-align:center;margin:0 34px 20px}.rulesBox p{line-height:1.55;margin:0 0 14px}.rulesClose{position:absolute;top:4px;right:6px;z-index:2;width:44px;height:44px;padding:0;border:none;background:transparent;color:inherit;font-size:32px;line-height:44px;text-align:center;cursor:pointer;touch-action:manipulation;-webkit-tap-highlight-color:transparent}#rulesButton{margin:10px;min-height:44px;touch-action:manipulation;-webkit-tap-highlight-color:transparent}
.sponsorBox{width:100%;min-height:180px;box-sizing:border-box;margin:18px 0 0;padding:0;border:1px solid var(--border);background:var(--surface-muted);display:flex;flex-direction:column;align-items:stretch;justify-content:flex-start;position:relative;overflow:hidden}.sponsorMessage{flex:1 1 auto;min-height:135px;display:flex;align-items:center;justify-content:center;box-sizing:border-box;padding:16px;font-size:10.8px;line-height:1.5;text-align:center;overflow-wrap:anywhere}.sponsorFooter{flex:0 0 45px;min-height:45px;box-sizing:border-box;display:flex;align-items:center;justify-content:center;padding:8px 12px;border-top:1px solid var(--border);background:var(--surface);overflow:hidden}.sponsorBox a{color:inherit;font-size:10.8px;font-weight:bold;text-decoration:none}.sponsorBox a:hover,.sponsorBox a:focus-visible{text-decoration:underline}.sponsorLink{display:block;max-width:100%;overflow-wrap:anywhere;text-align:center}.sponsorLink:hover,.sponsorLink:focus-visible{text-decoration:none}
.siteHeader{display:flex;align-items:center;justify-content:space-between;max-width:900px;margin:0 auto 10px}.siteHeaderBrand{font-size:38px;font-weight:bold}.headerControls{display:flex;align-items:center;gap:8px}.moreButton,.themeToggle{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:42px;box-sizing:border-box;padding:8px 12px;background:var(--surface);color:var(--text)}.hamburgerIcon{font-size:22px;line-height:1}.themeToggleIcon{font-size:18px;line-height:1}.moreMenu{position:absolute;top:64px;right:20px;z-index:1200;min-width:170px;padding:8px;background:var(--surface);color:var(--text);border:1px solid var(--border);text-align:left;box-shadow:0 8px 24px rgba(0,0,0,.15)}.moreMenu[hidden]{display:none}.gameMenuItem{display:block;padding:10px 12px;color:inherit;text-decoration:none}.gameMenuItem:hover,.gameMenuItem:focus-visible,.gameMenuItem.active{text-decoration:underline;font-weight:bold}.visuallyHidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.siteBottomBar{position:fixed;left:0;right:0;bottom:0;z-index:1999;min-height:46px;box-sizing:border-box;display:grid;grid-template-columns:1fr auto 1fr;align-items:center;padding:5px 12px;background:var(--surface);color:var(--text);border-top:1px solid var(--border)}.siteBottomLegal{justify-self:start;display:flex;align-items:center}.siteBottomVisitors{justify-self:center;display:flex;align-items:center;justify-content:center}.siteBottomCookies{justify-self:end;display:flex;align-items:center}.siteVisitorCounter{display:flex;justify-content:center;align-items:center;min-height:20px;margin:0}.siteVisitorCounter img{display:block;width:110px;height:20px}.legalBitsLink{display:inline-flex;align-items:center;min-height:34px;box-sizing:border-box;padding:7px 10px;color:inherit;background:var(--surface);border:1px solid var(--border);border-radius:6px;font-size:12px;text-decoration:none;white-space:nowrap}.legalBitsLink:hover,.legalBitsLink:focus-visible{text-decoration:underline}.cookieSettingsLink{position:static;padding:7px 10px;font-size:12px;background:var(--surface);color:var(--text);border:1px solid var(--border);border-radius:6px}
.cookieBanner{position:fixed;left:16px;right:16px;bottom:62px;z-index:2000;box-sizing:border-box;max-width:900px;margin:0 auto;padding:18px 20px;background:var(--surface);color:var(--text);border:1px solid var(--border);border-radius:12px;box-shadow:0 12px 40px rgba(0,0,0,.28);text-align:left}.cookieBanner h2{margin:0 0 8px;font-size:22px;font-weight:bold}.cookieBanner p{margin:0 0 10px;line-height:1.5}.cookieLinks a{color:inherit;text-decoration:underline}.cookieActions{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px}.cookieActions button{min-height:42px}.cookiePrimary{font-weight:bold}.cookieSecondary{background:var(--surface)}.cookieSettingsPanel h2{font-size:22px;margin:0 0 10px;font-weight:bold}.cookieChoice{display:flex;align-items:flex-start;gap:10px;padding:12px;border:1px solid var(--border);border-radius:8px}.cookieChoice input{width:20px;height:20px;margin:2px 0 0;flex:0 0 auto}.cookieChoice span{display:flex;flex-direction:column;gap:4px}.cookieChoice small{color:var(--muted);line-height:1.4}
@media(max-width:480px){body{margin:12px;padding-bottom:58px}h1{font-size:32px}.shareBox{width:min(94%,420px);padding:18px}.shareGraphic{padding:16px 10px}.shareStatsRow .shareStat strong{font-size:20px}.shareButtons button{flex:1 1 40%;min-width:0}.rulesModal{padding:12px}.rulesBox{width:calc(100vw - 24px);max-width:none;max-height:calc(100vh - 24px);max-height:calc(100dvh - 24px);padding:46px 18px 22px;border-radius:14px}.rulesBox h2{font-size:24px;margin:0 34px 18px}.rulesBox p{font-size:16px;line-height:1.5}.siteHeaderBrand{font-size:32px}.siteHeader{gap:8px}.headerControls{gap:4px}.moreButton,.themeToggle{min-height:42px;padding:8px 10px}.moreMenu{top:56px;right:12px}.date-navigation button{width:58px;min-width:58px;height:52px;font-size:40px}.date-navigation #currentDate{min-width:150px;min-height:52px}.siteBottomBar{grid-template-columns:1fr auto 1fr;padding:4px 6px;min-height:44px}.legalBitsLink,.cookieSettingsLink{font-size:10px;padding:6px 7px;min-height:32px}.siteVisitorCounter img{width:90px;height:auto}.cookieBanner{left:8px;right:8px;bottom:54px;padding:16px;max-height:calc(100dvh - 62px);overflow:auto}.cookieActions button{flex:1 1 100%}}
#resetButton{display:none!important}


@keyframes active-cell-pulse {
    0%, 100% { box-shadow: 0 0 0 0 rgba(255, 255, 255, 0); transform: scale(1); }
    50% { box-shadow: 0 0 0 4px rgba(255, 255, 255, 0.45); transform: scale(1.025); }
}

.cell.activeChainPulse {
    animation: active-cell-pulse 2.4s ease-in-out infinite;
    position: relative;
    z-index: 1;
}

@media (prefers-reduced-motion: reduce) {
    .cell.active { animation: none; }
}

/* Puzzle tools */
.toolsButton{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:42px;padding:8px 12px;background:var(--surface);color:var(--text);border:1px solid var(--border);font:inherit;cursor:pointer}
.toolsModal{position:fixed;inset:0;z-index:1300;display:flex;align-items:center;justify-content:center;padding:12px}
.toolsModal[hidden]{display:none}
.toolsOverlay{position:absolute;inset:0;background:var(--overlay)}
.toolsBox{position:relative;z-index:1;width:min(420px,calc(100vw - 24px));box-sizing:border-box;padding:42px 22px 22px;background:var(--surface);color:var(--text);border:1px solid var(--border);border-radius:16px;box-shadow:0 20px 60px rgba(0,0,0,.35);text-align:left}
.toolsBox h2{text-align:center;margin:0 30px 18px}
.toolsClose{position:absolute;top:4px;right:6px;width:44px;height:44px;padding:0;border:0;background:transparent;color:inherit;font-size:32px;cursor:pointer}
.toolsOptions{display:flex;flex-direction:column;gap:10px}
.toolsOptions label,.toolsAction{display:flex;align-items:center;gap:12px;min-height:46px;box-sizing:border-box;padding:10px 12px;border:1px solid var(--border);background:var(--surface);color:var(--text);font:inherit}
.toolsOptions input{width:20px;height:20px;flex:0 0 auto}
.toolsAction{width:100%;text-align:left;cursor:pointer}
.toolsFinalNumber{margin:10px 0;font-size:18px;font-weight:bold}
body.tools-reverse .toolsButton{font-weight:bold}
@media(max-width:480px){.toolsButton{min-height:42px;padding:8px 10px}.toolsBox{padding:42px 16px 18px}}

.toolsOptions label:has(select){justify-content:space-between}.toolsOptions select{min-width:72px;padding:7px 10px;font:inherit;background:var(--surface);color:var(--text);border:1px solid var(--border)}

.chainDirectionRow{display:flex;align-items:center;justify-content:center;gap:6px;margin:4px 0 10px;font-size:16px}.chainDirectionRow button{min-width:36px;min-height:32px;padding:4px 10px;border:1px solid var(--border);background:var(--surface);color:var(--text);font:inherit;cursor:pointer}.chainDirectionRow button.active{font-weight:700;outline:2px solid currentColor;outline-offset:-2px}

.chainDirectionRow .clearChainButton{margin-left:8px;min-width:58px}

.chainDirectionRow .clearAllButton{margin-left:4px;min-width:72px}.chainDirectionRow button[hidden]{display:none}


/* Under-development notice */
.constructionNotice{border:0;border-radius:12px;padding:0;max-width:min(92vw,520px);width:calc(100% - 2rem);background:transparent;color:inherit;box-shadow:0 18px 50px rgba(0,0,0,.3)}
.constructionNotice::backdrop{background:rgba(0,0,0,.68)}
.constructionNoticeBox{padding:1.5rem;background:var(--surface,#fff);color:var(--text,#111);border:2px solid currentColor;border-radius:12px;text-align:center}
.constructionNoticeBox h2{margin:0 0 1rem;font-size:1.35rem}
.constructionNoticeBox p{margin:0 0 1.25rem;line-height:1.5}
.constructionNoticeBox button{padding:.65rem 1rem;font:inherit;border:1px solid currentColor;border-radius:8px;background:transparent;color:inherit;cursor:pointer}