:root{color-scheme:light;--paper:#f6f4ed;--surface:#fffdf7;--ink:#292722;--muted:#777367;--red:#a63129;--red-dark:#86241e;--border:#ddd8cb;font-family:Inter,"Microsoft YaHei","PingFang SC",system-ui,sans-serif;color:var(--ink);background:var(--paper)}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:28px}body{margin:0}a{color:inherit;text-decoration:none}button{font:inherit;cursor:pointer}button,a,summary{-webkit-tap-highlight-color:transparent}button:focus-visible,a:focus-visible,summary:focus-visible{outline:3px solid #bd6359;outline-offset:4px}[hidden]{display:none!important}.skip-link{position:absolute;top:-90px;left:20px;padding:12px;background:var(--surface);z-index:20}.skip-link:focus{top:8px}.site-header{border-top:4px solid var(--red);border-bottom:1px solid var(--border);background:var(--surface)}.header-inner{max-width:1648px;margin:auto;min-height:80px;padding:14px 28px;display:flex;align-items:center;gap:48px}.wordmark{display:flex;align-items:center;gap:12px;font-family:"Songti SC",SimSun,serif;font-size:23px;font-weight:700;letter-spacing:2px;white-space:nowrap}.wordmark small{display:block;font:9px/1.5 system-ui,sans-serif;letter-spacing:2.6px;color:var(--muted);margin-top:4px}.seal{display:grid;place-items:center;color:var(--surface);background:var(--red);font:30px/1 SimSun,serif;border-radius:12px;width:48px;height:48px;position:relative}.seal:before{content:"";position:absolute;inset:6px;border:1px solid #e7b7a5;border-radius:50%}.site-nav{display:flex;gap:30px;font-size:14px}.site-nav a{padding:9px 0;color:var(--muted)}.site-nav a:hover,.site-nav a[aria-current]{color:var(--red)}.preview-label{margin-left:auto;display:flex;align-items:center;gap:7px;font-size:11px;color:var(--muted);white-space:nowrap}.preview-label i{width:6px;height:6px;border-radius:50%;background:#a7905d}.page-shell{max-width:1648px;margin:auto;padding:28px 28px 48px}.page-intro{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;margin-bottom:20px}.eyebrow{font-size:10px;letter-spacing:1.7px;color:var(--muted);margin:0 0 9px;font-weight:500}.page-intro h1{font:600 26px/1.25 "Songti SC",SimSun,serif;margin:0;letter-spacing:1px}.page-intro>p{font-size:13px;color:var(--muted);margin:0 0 4px}.play-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:24px;align-items:start}.game-panel{min-width:0;background:var(--surface);border:1px solid var(--border);border-radius:12px;overflow:hidden;box-shadow:0 8px 30px #30261408}.game-toolbar{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:12px 16px;min-height:61px;border-bottom:1px solid var(--border)}.mode-group{display:flex;align-items:center;gap:4px;background:#f0ede4;border-radius:7px;padding:3px}.mode-button{border:0;padding:8px 13px;border-radius:5px;color:var(--muted);background:transparent;font-size:12px;white-space:nowrap}.mode-button.active{background:var(--surface);box-shadow:0 1px 4px #3026140e;color:var(--red);font-weight:600}.game-actions{display:flex;align-items:center;gap:15px}.quiet-button{border:0;background:none;color:var(--muted);font-size:11px;display:flex;align-items:center;gap:5px;padding:6px 0;white-space:nowrap}.quiet-button:hover{color:var(--red)}.quiet-button svg{width:15px;height:15px;stroke:currentColor;stroke-width:1.7;fill:none}.game-viewport{height:clamp(600px,calc(100svh - 215px),880px);position:relative;background:#efeae0}.game-viewport iframe{display:block;width:100%;height:100%;border:0}.game-caption{display:flex;justify-content:space-between;gap:12px;padding:11px 16px;color:var(--muted);font-size:10px;line-height:1.6}.game-caption a{text-decoration:underline;text-underline-offset:3px}.side-rail{min-width:0}.advertisement{margin-bottom:28px}.ad-heading{display:flex;justify-content:space-between;color:#918b7e;font-size:9px;letter-spacing:1px;margin:1px 0 9px}.owner-ad{width:300px;height:250px;border:1px solid var(--border);background:#efede6;overflow:hidden}.ad-placeholder{height:100%;display:flex;flex-direction:column;align-items:center;justify-content:center;background:linear-gradient(135deg,#f4f1e9,#eeece4);color:#938b7b;position:relative}.ad-dimensions{position:absolute;top:15px;left:15px;font-size:9px;letter-spacing:1.5px}.ad-placeholder-mark{font:28px/1 system-ui;color:#bfb7a7;margin-bottom:18px}.ad-placeholder strong{font-weight:500;font-size:14px;letter-spacing:2px}.ad-placeholder p{font-size:11px;margin:10px 0 24px}.ad-placeholder small{font-size:9px;color:#999182}.ad-status{font-size:10px;color:var(--muted);line-height:1.6;margin:9px 0 0;min-height:16px}.ad-button{margin-top:8px;background:var(--surface);border:1px solid var(--border);border-radius:5px;padding:7px 10px;font-size:11px;color:var(--ink)}.first-game{border-top:1px solid var(--border);padding-top:23px}.first-game h2{font:500 28px/1.5 "Songti SC",SimSun,serif;letter-spacing:1px;margin:10px 0 20px}.first-game ol{list-style:none;margin:0;padding:0;display:grid;gap:17px}.first-game li{display:flex;gap:13px}.first-game li>span{font:12px/1.6 Georgia,serif;color:var(--red);padding-top:1px}.first-game strong{font-size:12px;font-weight:500}.first-game li p{margin:5px 0 0;font-size:11px;line-height:1.7;color:var(--muted)}.text-link{display:flex;justify-content:space-between;margin-top:23px;padding-bottom:12px;border-bottom:1px solid var(--border);font-size:12px;color:var(--red)}.account-note{font-size:10px;line-height:1.9;color:#8b867a;margin:17px 0}.rules-section{margin-top:56px}.section-heading{display:flex;justify-content:space-between;align-items:end;gap:20px;margin-bottom:22px}.section-heading h2{font:500 24px/1.4 "Songti SC",SimSun,serif;margin:0}.section-heading>p{font-size:11px;line-height:1.8;color:var(--muted);margin:0}.piece-rules{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));border-top:1px solid var(--border);border-left:1px solid var(--border);background:var(--surface)}.piece-rules details{border-right:1px solid var(--border);border-bottom:1px solid var(--border)}.piece-rules summary{list-style:none;display:flex;align-items:center;gap:12px;padding:20px 17px;cursor:pointer;font-size:12px}.piece-rules summary::-webkit-details-marker{display:none}.piece-glyph{width:34px;height:34px;flex-shrink:0;display:grid;place-items:center;border:1px solid #bb7167;border-radius:50%;color:var(--red);font:23px/1 SimSun,serif}.detail-toggle{margin-left:auto;color:#a59c8c;font-size:17px}.piece-rules details[open] .detail-toggle{transform:rotate(45deg)}.piece-rules details p{padding:0 17px 17px;margin:0;color:var(--muted);font-size:12px;line-height:1.9}.practice-section{display:flex;align-items:center;gap:26px;margin-top:36px;padding:30px 32px;background:#eee9df;border:1px solid #e4dcce}.practice-seal{display:grid;place-items:center;width:66px;height:66px;flex-shrink:0;border:1px solid var(--red);border-radius:50%;font:44px SimSun,serif;color:var(--red)}.practice-section h2{font:500 20px/1.5 "Songti SC",SimSun,serif;margin:0 0 10px}.practice-section p:not(.eyebrow){font-size:12px;color:var(--muted);line-height:1.9;margin:0}.primary-button{margin-left:auto;padding:13px 18px;display:flex;align-items:center;gap:23px;background:var(--red);color:var(--surface);border:0;border-radius:6px;font-size:12px;white-space:nowrap}.primary-button:hover{background:var(--red-dark)}.site-footer{max-width:1648px;margin:auto;padding:22px 28px;border-top:1px solid var(--border);display:flex;justify-content:space-between;gap:14px;font-size:10px;color:var(--muted)}.game-panel.expanded{position:fixed;inset:12px;z-index:50;display:flex;flex-direction:column;box-shadow:0 0 0 100vmax #1d191dcc}.game-panel.expanded .game-viewport{height:auto;flex:1;min-height:0}.game-panel.expanded .game-caption{flex-shrink:0}body.game-expanded{overflow:hidden}
@media(min-width:1500px){.game-viewport{min-height:710px}}@media(max-width:1020px){.header-inner{gap:32px}.site-nav{gap:20px}.play-layout{grid-template-columns:minmax(0,1fr)}.game-viewport{height:680px}.side-rail{display:grid;grid-template-columns:300px 1fr;gap:20px 30px}.advertisement{margin:0}.first-game{border-top:0;padding:12px 0 0}.first-game h2{font-size:23px;margin:0 0 15px}.first-game h2 br{display:none}.first-game ol{gap:12px}.first-game .text-link{margin-top:18px}.account-note{grid-column:1/-1;margin:0}.piece-rules{grid-template-columns:repeat(3,minmax(0,1fr))}.rules-section{margin-top:42px}.practice-seal{display:none}}@media(max-width:640px){.header-inner{min-height:68px;padding:12px 16px;gap:12px;flex-wrap:wrap}.wordmark{font-size:19px}.wordmark small{font-size:8px;letter-spacing:1.5px}.seal{width:39px;height:39px;font-size:25px}.site-nav{order:3;width:100%;border-top:1px solid var(--border);padding-top:7px;gap:25px;font-size:12px}.preview-label{font-size:9px}.page-shell{padding:20px 12px 30px}.page-intro{margin-bottom:14px}.page-intro h1{font-size:22px}.page-intro>p{display:none}.eyebrow{font-size:9px;margin-bottom:6px}.game-toolbar{padding:9px 10px;min-height:53px;gap:5px}.mode-button{font-size:11px;padding:7px 10px}.game-actions{gap:10px}.quiet-button{font-size:10px}.quiet-button svg{width:13px;height:13px}.game-viewport{height:max(580px,calc(100svh - 180px))}.game-caption{padding:9px 10px;font-size:9px;flex-wrap:wrap;gap:4px}.side-rail{display:flex;flex-direction:column;gap:25px}.advertisement{width:300px;margin:auto}.first-game{padding:22px 8px 0;border-top:1px solid var(--border)}.first-game h2{font-size:25px}.first-game li p{font-size:12px}.first-game li strong{font-size:13px}.account-note{margin:0 8px}.section-heading{display:block;margin-bottom:17px}.section-heading h2{font-size:21px}.section-heading>p{margin-top:8px;font-size:10px}.piece-rules{grid-template-columns:repeat(2,minmax(0,1fr))}.piece-rules summary{padding:15px 10px;font-size:11px;gap:7px}.piece-glyph{width:29px;height:29px;font-size:20px}.piece-rules details p{padding:0 12px 15px;font-size:11px}.practice-section{display:block;padding:23px 20px;margin-top:26px}.practice-section h2{font-size:19px}.primary-button{margin-top:20px;width:100%;justify-content:space-between}.site-footer{display:block;padding:20px 16px;line-height:2}.site-footer>span{display:block}.game-panel.expanded{inset:0;border-radius:0}.game-panel.expanded .game-caption{display:none}}
/* The embedded mobile board sizes itself from the window height. A proportional
   window keeps all nine files visible rather than forcing a tall, narrow board. */
@media(max-width:640px){.game-viewport{height:auto;aspect-ratio:.66;min-height:460px;max-height:700px}.game-panel.expanded .game-viewport{flex:0 0 auto;height:min(calc(100dvh - 54px),calc(100vw * 1.42));aspect-ratio:auto}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
.policy-page{max-width:840px;margin:0 auto;padding:48px 28px 64px;font-size:15px;line-height:1.9}.policy-page h1{font:600 30px/1.4 "Songti SC",SimSun,serif;margin:0 0 24px}.policy-page h2{font:600 21px/1.5 "Songti SC",SimSun,serif;margin:32px 0 12px}.policy-page p{margin:0 0 16px}.policy-page a{color:var(--red);text-decoration:underline;text-underline-offset:3px;overflow-wrap:anywhere}@media(max-width:640px){.policy-page{padding:30px 20px 40px;font-size:14px}.policy-page h1{font-size:26px}}