@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;600;700&family=Noto+Sans+JP:wght@400;500;600;700;800&display=swap');

:root{--paper:#f5f4ef;--ink:#243a32;--muted:#81877e;--line:#dedfd5;--green:#355b47;--mint:#b5d2bb;--orange:#d89b75;--board:#28463c;--font:'DM Sans','Noto Sans JP',sans-serif;color-scheme:light}
*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--font);font-size:14px;-webkit-font-smoothing:antialiased}button,select,input{font:inherit}button{cursor:pointer}button,a,select,input{-webkit-tap-highlight-color:transparent}button{color:inherit}button:disabled{cursor:default;opacity:.36}button:focus-visible,a:focus-visible,select:focus-visible,input:focus-visible{outline:3px solid #d99e76;outline-offset:4px}svg{display:block}button svg{width:19px;height:19px;stroke:currentColor;fill:none;stroke-linecap:round;stroke-linejoin:round;stroke-width:1.5}button{border:0;background:none}a{color:inherit;text-decoration:none}.site-wrap{max-width:1180px;padding:0 54px;margin:auto}.site-header{height:99px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:13px}.brand-mark{display:grid;grid-template-columns:repeat(2,12px);gap:3px;transform:rotate(-8deg)}.brand-mark i{width:12px;height:12px;border-radius:50%;background:var(--ink)}.brand-mark i:nth-child(2),.brand-mark i:nth-child(3){background:#a6bba3}.wordmark{font-size:28px;font-weight:700;letter-spacing:2px;display:flex;align-items:center;gap:18px}.brand-sub{font-size:11px;letter-spacing:.11em;font-weight:500;padding-left:18px;border-left:1px solid #cad0c4}.site-header nav{display:flex;gap:24px;align-items:center}.icon-button{width:34px;height:34px;border-radius:50%;display:grid;place-items:center}.icon-button:hover{background:#e8e9e1}.sound-button svg{width:19px;height:19px}.sound-on{display:none}.sound-button[aria-pressed=true] .sound-on{display:block}.sound-button[aria-pressed=true] .sound-off{display:none}.rules-button{display:flex;align-items:center;gap:8px;font-size:12px;font-weight:500}.question-icon{width:17px;height:17px;border:1px solid #5c6b60;border-radius:50%;font-size:11px;display:grid;place-items:center}.intro{display:flex;align-items:center;justify-content:space-between;padding:40px 0 38px}.eyebrow{font-size:10px;font-weight:600;letter-spacing:.18em;margin:0 0 14px;display:flex;align-items:center;gap:8px}.eyebrow>span{width:6px;height:6px;border-radius:50%;background:#7b9d78}h1{font-size:40px;letter-spacing:.035em;line-height:1.45;font-weight:700;margin:0}.heading-dot{color:#7c9c78}.intro-aside{display:flex;align-items:center;gap:15px;padding-right:12px}.intro-aside svg{width:148px;height:110px}.topology-tag{font-size:9px;letter-spacing:.14em;color:#7b8375}.intro-aside p{font-size:12px;line-height:2;margin:10px 0 0;color:#7a8175}.game-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:56px;align-items:start}.board-topline{display:flex;align-items:center;justify-content:space-between;margin-bottom:14px}.board-caption{font-size:10px;letter-spacing:.17em;font-weight:600}.round-label{font-size:14px;font-weight:500;font-variant-numeric:tabular-nums}.round-label span{font-size:9px;color:#7f897e;letter-spacing:.1em;margin-left:3px}.board-shell{background:#203d33;position:relative;padding:31px 31px 29px;border-radius:14px;box-shadow:0 18px 35px -25px #18362a99,0 2px 0 #182f26;isolation:isolate}.board-shell:before{content:'';position:absolute;inset:4px;border:1px solid #7b98752b;border-radius:11px;z-index:-1}.board{display:grid;grid-template-columns:repeat(8,minmax(0,1fr));aspect-ratio:1;background:#58706155;border:1px solid #55705c70;gap:1px}.cell{padding:0;display:grid;place-items:center;position:relative;background:#2c493e;min-width:0;aspect-ratio:1;border-radius:0;transition:background .18s}.cell:nth-child(16n+2),.cell:nth-child(16n+4),.cell:nth-child(16n+6),.cell:nth-child(16n+8),.cell:nth-child(16n+9),.cell:nth-child(16n+11),.cell:nth-child(16n+13),.cell:nth-child(16n+15){background:#2b473d}.cell:focus-visible{outline:2px solid var(--mint);outline-offset:-3px;z-index:3}.cell.legal:hover,.cell.preview-at{background:#3b604c}.cell.preview-capture{background:#426149}.cell.wrapped-capture{background:#6e6350}.disc{position:relative;width:76%;height:76%;border-radius:50%;pointer-events:none;box-shadow:1px 4px 5px #10251d7a;transition:background .15s}.disc.black{background:radial-gradient(circle at 34% 26%,#364038,#17231c 62%,#111c16);border:1px solid #12221a;box-shadow:inset 0 1px 2px #677b6340,1px 4px 4px #0f251d7a}.disc.white{background:radial-gradient(circle at 30% 25%,#fffef7,#e8eadb 65%,#cdd3be);border:1px solid #e8ecde;box-shadow:inset 0 -2px 3px #b3bba06b,1px 4px 4px #10251d7a}.disc.last:after{content:'';position:absolute;width:6px;height:6px;border-radius:50%;top:calc(50% - 3px);left:calc(50% - 3px);background:#8aab81}.disc.black.last:after{background:#b3cc9c}.disc.flip{animation:flip .42s ease-in-out}.disc.placed{animation:place .3s ease-out}.legal-dot{height:16%;width:16%;border:1px solid #b6d2a77a;border-radius:50%;background:#a7c89517;pointer-events:none}.cell.legal:hover .legal-dot,.cell.preview-at .legal-dot{width:69%;height:69%;background:#a5c09b27;border:1px dashed 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#e3e5da;border-radius:9px;gap:0;text-align:center}.player-name{display:flex;align-items:center;justify-content:center;gap:5px;font-size:10px;white-space:nowrap}.mini-disc{width:13px;height:13px;border-radius:50%;display:inline-block;vertical-align:middle;flex-shrink:0}.mini-disc.black{background:#2a392a;box-shadow:inset 0 1px 1px #57634b}.mini-disc.white{background:#fffef6;border:1px solid #d0d7c3}.player-color{font-size:8px;color:#8b9380}.score-number{font-size:48px;font-weight:500;letter-spacing:-.05em;line-height:1.35;font-variant-numeric:tabular-nums}.player-meta{font-size:8px;letter-spacing:.1em;color:#8c9582}.player-score.active .player-meta{color:#547d43}.score-separator{color:#a6ac99;padding-top:35px;font-size:20px}.score-track{grid-column:1/-1;display:flex;height:4px;border-radius:3px;overflow:hidden;background:#dce1d0;margin-top:16px}.score-track span{width:50%;transition:width .4s}.score-track #black-track{background:#344a32}.score-track 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#d99e76;outline-offset:3px}.actions{display:flex;gap:9px}.actions button{display:flex;align-items:center;justify-content:center;gap:7px;min-height:40px;border-radius:5px;font-size:10px}.undo-button{border:1px solid #d7decb;width:107px;flex-shrink:0}.undo-button>span{font-size:19px;line-height:1}.undo-button:hover:not(:disabled){background:#e6ebdf}.restart-button{background:#3c5837;color:#f5f6ed;flex:1}.restart-button:hover{background:#2b4828}.restart-button svg{width:14px;height:14px}.torus-note{margin-top:30px;padding:19px 0 0;border-top:1px solid var(--line)}.note-label{font-size:11px;font-weight:500}.note-label>span{color:#ba8c62;margin-right:6px}.torus-note p{font-size:10px;color:#87907d;line-height:2;margin:9px 0 8px}.torus-note button{padding:3px 0;font-size:9px;color:#5e7851;border-bottom:1px solid #acbaa0}.torus-note button span{margin-left:12px}.last-move{display:flex;align-items:center;gap:20px;border-top:1px solid var(--line);padding:19px 0 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dialog{border:1px solid #e1e5d6;color:var(--ink);background:#f8f7f1;border-radius:15px;padding:40px;max-width:calc(100% - 32px);box-shadow:0 35px 100px #122d2540}dialog::backdrop{background:#14271e88;backdrop-filter:blur(5px)}.dialog-close{position:absolute;right:15px;top:13px;font-size:26px;color:#8a9580}.rules-dialog{width:540px}.rules-dialog h2{font-size:28px;line-height:1.6;letter-spacing:.04em;margin:0 0 13px}dialog h2{font-weight:600}.dialog-intro{font-size:11px;color:#87907d;line-height:1.9;margin:0 0 21px}.rule-item{display:flex;gap:18px;padding:18px 0;border-top:1px solid var(--line)}.rule-number{font-size:12px;color:#9caa8b;padding-top:2px}.rule-item h3{font-size:13px;font-weight:600;margin:0 0 8px}.rule-item p{font-size:11px;line-height:1.9;color:#7b8871;margin:0}.rule-item p.rule-small{font-size:9px;margin-top:10px}.wrap-example{display:flex;align-items:center;gap:5px;padding:13px 12px 20px;margin-top:12px;background:#e5e9dd;border-radius:5px}.example-new{color:#405a34;font-size:23px;position:relative}.example-new small{position:absolute;top:29px;left:50%;transform:translateX(-50%);font-size:7px;white-space:nowrap;color:#738167}.example-line{flex:1;border-bottom:1px dashed #afbaa4;margin:0 8px}.example-disc{font-size:23px;color:#2f4027}.example-disc.pale{color:#fffef6;text-shadow:0 1px 2px #687c4d}.example-edge{font-size:18px;color:#c18b60;margin:0 5px;border-left:1px dashed #b8c4a9;border-right:1px dashed #b8c4a9;padding:0 7px}.primary-button{background:#3c5837;color:#f7f8ef;border-radius:6px;min-height:44px;display:flex;align-items:center;justify-content:space-between;padding:11px 18px;font-size:12px;gap:28px}.primary-button:hover{background:#294827}.rules-dialog>.primary-button{width:100%;margin-top:10px}.confirm-dialog{width:440px}.confirm-dialog h2{font-size:23px;margin:20px 0 12px}.confirm-dialog p:not(.eyebrow){font-size:12px;line-height:1.9;color:#7b8871}.dialog-actions{display:flex;justify-content:flex-end;gap:12px;margin-top:30px}.secondary-button{font-size:12px;padding:10px 20px;border:1px solid #d7decb;border-radius:6px}.result-dialog{text-align:center;width:390px;padding-top:35px}.result-symbol{font-size:68px;line-height:1.3;color:#839e6d}.result-dialog .eyebrow{display:block;margin-top:15px;font-size:8px}.result-dialog h2{font-size:27px;margin:20px 0 10px}.result-dialog>p:not(.eyebrow){color:#7e8c71;font-size:12px}.result-score{font-size:43px;display:flex;align-items:center;justify-content:center;gap:18px;margin:25px 0 30px;font-variant-numeric:tabular-nums}.result-score .mini-disc{width:23px;height:23px}.result-score .colon{color:#a2af93;font-size:25px}.result-dialog>.primary-button{width:100%}.result-review{margin-top:18px;font-size:11px;color:#7b8c6c}.toast{animation:notice .35s ease} .cell.invalid{animation:invalid .3s}
@keyframes flip{0%{transform:scaleX(1)}48%{transform:scaleX(.05)}100%{transform:scaleX(1)}}@keyframes place{from{transform:scale(.7);opacity:.3}to{transform:scale(1);opacity:1}}@keyframes pulse{50%{opacity:.35}}@keyframes notice{from{opacity:.3;transform:translateY(3px)}to{opacity:1;transform:translateY(0)}}@keyframes invalid{50%{background:#78614b}}
@media(min-width:1400px){.site-wrap{max-width:1240px;padding:0 64px}.intro{padding-top:43px;padding-bottom:42px}.game-layout{gap:70px;grid-template-columns:minmax(0,1fr) 315px}.game-panel{padding-top:4px}.turn-state{margin-bottom:24px}.settings{padding-top:30px}.torus-note{margin-top:35px}}
@media(max-width:1000px){.site-wrap{padding:0 32px}.game-layout{gap:30px;grid-template-columns:minmax(0,1fr) 268px}.intro-aside{padding-right:0;gap:6px}.intro-aside svg{width:120px}h1{font-size:36px}.board-shell{padding:27px 27px 25px}.column-labels{left:27px;right:27px;top:9px}.row-labels{top:27px;bottom:25px;left:10px}.board-bottom-label{bottom:8px;font-size:6px}.board-under{align-items:flex-start;flex-direction:column;gap:9px}.turn-state p{font-size:17px}.scoreboard{padding:15px 8px 18px}.settings{padding-top:20px}.torus-note{margin-top:20px;padding-top:15px}.score-number{font-size:43px}}
@media(max-width:760px){.site-wrap{padding:0 23px;max-width:580px}.site-header{height:79px}.wordmark{font-size:23px;gap:11px}.brand-sub{font-size:9px;padding-left:11px}.site-header nav{gap:12px}.rules-button{font-size:10px}.intro{padding:29px 0 26px}.eyebrow{font-size:8px;margin-bottom:11px}h1{font-size:32px}.intro-aside{align-self:flex-end}.intro-aside svg{width:95px;height:92px}.intro-aside>div{display:none}.game-layout{display:flex;flex-direction:column;gap:8px}.board-column{width:100%}.board-shell{border-radius:12px;padding:28px 28px 26px}.column-labels{top:10px;left:28px;right:28px}.row-labels{top:28px;bottom:26px;left:11px}.board-caption{font-size:8px}.board-topline{margin-bottom:13px}.board-under{flex-direction:row;align-items:center;padding:16px 0 13px}.move-help{font-size:9px}.shift-controls>span{display:none}.shift-controls button{width:23px;height:24px}.game-panel{width:100%;display:grid;grid-template-columns:1fr 1fr;gap:0 22px;padding:12px 0 20px;border-top:1px solid var(--line)}.turn-state{grid-column:1/-1;margin-bottom:17px;min-height:44px}.turn-state p{font-size:17px}.turn-state div>span{font-size:9px}.scoreboard{grid-column:1;grid-row:2/4;align-self:start;padding:19px 7px 17px}.score-number{font-size:40px}.player-name{font-size:8px;gap:4px}.player-color{display:none}.player-meta{font-size:7px;letter-spacing:0}.score-separator{font-size:18px;padding-top:31px}.settings{grid-column:2;grid-row:2/4;padding:0}.setting-label{font-size:9px;margin-bottom:7px}.segmented{padding:3px}.segmented button{font-size:9px;gap:5px;height:29px}.segmented button svg{width:13px;height:13px}.difficulty-field{padding:12px 0;gap:5px}.difficulty-field label{font-size:8px;line-height:1.6}.select-wrap select{font-size:9px;min-width:70px;padding-left:8px;padding-right:21px}.select-wrap>span{font-size:14px;top:5px}.toggle-row{font-size:9px;padding:12px 0}.actions{grid-column:1/-1;margin-top:16px}.actions button{font-size:11px;min-height:42px}.undo-button{width:38%}.torus-note{grid-column:1/-1;display:grid;grid-template-columns:1fr auto;margin-top:21px;padding-top:16px;align-items:center;gap:8px}.note-label{font-size:10px}.torus-note p{grid-column:1;margin:0;font-size:9px}.torus-note button{grid-column:2;grid-row:1/3;font-size:8px;max-width:100px;line-height:1.8;text-align:left}.torus-note button span{margin-left:5px}.last-move{gap:10px;padding:16px 0;font-size:9px}.last-move-label{display:none}#remaining{font-size:8px}footer{padding:20px 0;font-size:7px;letter-spacing:.05em}.footer-mark{font-size:20px}dialog{padding:30px 25px}.rules-dialog{max-height:90dvh}.rules-dialog h2{font-size:25px}.rule-item{gap:13px;padding:16px 0}.rule-item p{font-size:10px}.dialog-intro{font-size:10px}.primary-button{font-size:11px}}
@media(max-width:370px){.site-wrap{padding:0 17px}.brand-sub{display:none}h1{font-size:28px}.game-panel{gap:0 14px}.board-shell{padding:24px 24px 23px}.column-labels{left:24px;right:24px;top:8px}.row-labels{top:24px;bottom:23px;left:9px}.board-bottom-label{font-size:5px}.board-under{gap:5px}.shift-controls button{width:20px}.move-help{font-size:8px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important}dialog::backdrop{backdrop-filter:none}}
.wrap-example{justify-content:center;gap:16px}.example-caption{font-size:9px;color:#869479}.example-new.pale{color:#fffef6;text-shadow:0 1px 2px #687c4d}
@media(min-width:761px){.site-wrap{max-width:1040px;padding:0 50px}.site-header{height:86px}.intro{padding:26px 0 27px}h1{font-size:36px;line-height:1.4}.game-layout{grid-template-columns:minmax(0,1fr) 300px;gap:48px}.turn-state{margin-bottom:16px;min-height:48px}.settings{padding-top:22px}.difficulty-field{padding:15px 0 13px}.toggle-row{padding:15px 0 19px}.torus-note{margin-top:24px;padding-top:16px}.torus-note p{line-height:1.8}}
@media(min-width:761px) and (max-width:1000px){.site-wrap{padding:0 32px}.game-layout{grid-template-columns:minmax(0,1fr) 268px;gap:30px}h1{font-size:34px}}
@media(max-width:480px){.brand-sub{display:none}.rules-button{white-space:nowrap}}