*,*:before,*:after{margin:0;padding:0;box-sizing:border-box}:root{--bg-primary: #0f0f1a;--bg-secondary: #1a1a2e;--bg-tertiary: #16213e;--bg-card: rgba(26, 26, 46, .85);--board-bg: #e8c88c;--board-bg-2: #d4a960;--board-line: #5c3a1e;--board-border: #3d2410;--red-piece: #c0392b;--red-piece-light: #e74c3c;--red-piece-bg: #f4d03f;--black-piece: #1a1a2e;--black-piece-light: #2c3e50;--black-piece-bg: #f4d03f;--accent: #d4af37;--accent-light: #f1c40f;--text-primary: #ecf0f1;--text-secondary: #95a5a6;--text-muted: #7f8c8d;--border-color: rgba(212, 175, 55, .2);--shadow: 0 4px 20px rgba(0, 0, 0, .4);--radius: 12px;--radius-sm: 8px;--transition: all .25s cubic-bezier(.4, 0, .2, 1)}html,body{height:100%;overflow-x:hidden}body{font-family:PingFang SC,Microsoft YaHei,Helvetica 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var(--border-color);z-index:100;flex-shrink:0}.app-title{font-size:20px;font-weight:700;color:var(--accent);letter-spacing:2px;display:flex;align-items:center;gap:8px}.app-title .title-icon{font-size:24px}.header-actions{display:flex;gap:8px;align-items:center}.main-content{flex:1;display:flex;gap:16px;padding:16px;max-width:1400px;width:100%;margin:0 auto;align-items:flex-start}.board-area{flex:1;display:flex;flex-direction:column;align-items:center;gap:12px;min-width:0}.side-panel{width:320px;flex-shrink:0;display:flex;flex-direction:column;gap:12px;max-height:calc(100vh - 100px);max-height:calc(100dvh - 100px);overflow-y:auto}.board-wrapper{width:100%;max-width:600px;position:relative}.board-container{width:100%;position:relative;background:linear-gradient(145deg,var(--board-bg) 0%,var(--board-bg-2) 100%);border-radius:var(--radius);box-shadow:0 8px 32px #00000080,inset 0 0 0 3px var(--board-border);aspect-ratio:9 / 10;overflow:hidden}.board-grid{position:absolute;top:5%;left:5%;right:5%;bottom:5%}.board-svg{position:absolute;top:0;left:0;width:100%;height:100%;pointer-events:none}.river-text{position:absolute;top:50%;transform:translateY(-50%);font-size:clamp(14px,3vw,22px);font-weight:700;color:var(--board-line);letter-spacing:8px;opacity:.6;pointer-events:none}.river-text.left{left:15%}.river-text.right{right:15%}.intersection{position:absolute;width:11%;height:10%;transform:translate(-50%,-50%);display:flex;align-items:center;justify-content:center;cursor:pointer;z-index:2}.intersection:before{content:"";position:absolute;width:70%;height:70%;border-radius:50%;background:transparent;transition:var(--transition)}.intersection.selectable:before{background:#2ecc7159;box-shadow:0 0 12px #2ecc71a6}.intersection.selected-sq:before{background:#f1c40f59;box-shadow:0 0 14px #f1c40fb3;border:2px solid rgba(241,196,15,.85)}.intersection.capture-target:before{background:#e74c3c47;box-shadow:0 0 14px #e74c3cb3;border:2.5px solid rgba(231,76,60,.9);animation:capturePulse .9s ease-in-out infinite}.intersection.last-move:before{background:#f1c40f47;box-shadow:0 0 10px #f1c40f73;border:2px solid rgba(241,196,15,.55)}.intersection.last-move-from:before{background:#f1c40f2e;border-style:dashed}.intersection.last-move-to:before{background:#e67e226b;box-shadow:0 0 18px #e67e22bf;border:3px solid rgba(230,126,34,.95);animation:lastMoveFlash 1.2s ease-out}.intersection.hint:before{background:#3498db73;box-shadow:0 0 18px #3498dbd9;animation:hintPulse .8s ease-in-out infinite}.intersection.hint-from:before{background:#3498db59;border:3px dashed rgba(52,152,219,.95);box-shadow:0 0 16px #3498dbb3}.intersection.hint-to:before{background:#2ecc7173;border:3px solid rgba(46,204,113,1);box-shadow:0 0 22px #2ecc71e6;animation:hintPulse .7s ease-in-out infinite}.intersection.check:before{background:#e74c3c80;box-shadow:0 0 24px #e74c3cf2,0 0 48px #ff502873;border:3px solid 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var(--accent-light);z-index:10}.piece:hover:not(.disabled){transform:scale(1.05)}.piece.disabled{cursor:default}.piece.moving{animation:pieceMove .3s ease-out}.piece.captured-anim{animation:pieceCapture .45s ease-out forwards;z-index:4}.piece.hint-piece{transform:scale(1.12);box-shadow:0 0 0 4px #3498dbd9,0 4px 18px #3498db8c;z-index:12;animation:hintPiecePulse 1s ease-in-out infinite}.piece.flying{position:absolute;width:8.8%;height:8%;transform:translate(-50%,-50%);z-index:30;pointer-events:none;box-shadow:0 6px 18px #00000073,inset 0 -2px 4px #0003}.player-bar{width:100%;max-width:600px;display:flex;align-items:center;justify-content:space-between;padding:10px 16px;background:var(--bg-card);border-radius:var(--radius-sm);border:1px solid var(--border-color);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px)}.player-info{display:flex;align-items:center;gap:10px}.player-avatar{width:36px;height:36px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:18px;font-weight:700;flex-shrink:0}.player-avatar.red{background:linear-gradient(135deg,var(--red-piece-light),var(--red-piece));color:#fff;box-shadow:0 0 10px #e74c3c66}.player-avatar.black{background:linear-gradient(135deg,var(--black-piece-light),var(--black-piece));color:#fff;box-shadow:0 0 10px #2c3e5066}.player-name{font-size:14px;font-weight:600}.player-status{font-size:12px;color:var(--text-secondary)}.player-timer{font-size:18px;font-weight:700;font-variant-numeric:tabular-nums;color:var(--accent);min-width:60px;text-align:right}.player-timer.warning{color:var(--red-piece-light);animation:pulse 1s ease-in-out infinite}.player-bar.active{border-color:var(--accent);box-shadow:0 0 12px #d4af3733}.panel-card{background:var(--bg-card);border-radius:var(--radius-sm);border:1px solid var(--border-color);padding:14px;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px)}.panel-title{font-size:13px;font-weight:600;color:var(--text-secondary);text-transform:uppercase;letter-spacing:1px;margin-bottom:10px;display:flex;align-items:center;justify-content:space-between}.btn{padding:8px 16px;border:none;border-radius:var(--radius-sm);font-size:14px;font-weight:600;cursor:pointer;transition:var(--transition);display:inline-flex;align-items:center;justify-content:center;gap:6px;white-space:nowrap}.btn:disabled{opacity:.4;cursor:not-allowed}.btn-primary{background:linear-gradient(135deg,var(--accent),var(--accent-light));color:var(--bg-primary)}.btn-primary:hover:not(:disabled){transform:translateY(-1px);box-shadow:0 4px 12px #d4af3766}.btn-secondary{background:#ffffff14;color:var(--text-primary);border:1px solid var(--border-color)}.btn-secondary:hover:not(:disabled){background:#ffffff26;border-color:var(--accent)}.btn-danger{background:#e74c3c33;color:var(--red-piece-light);border:1px solid rgba(231,76,60,.3)}.btn-danger:hover:not(:disabled){background:#e74c3c4d}.btn-icon{width:36px;height:36px;padding:0;border-radius:50%}.btn-sm{padding:6px 12px;font-size:12px}.btn-group{display:flex;gap:8px;flex-wrap:wrap}.btn-group .btn{flex:1}.move-history{max-height:300px;overflow-y:auto;font-size:13px}.move-history-list{display:flex;flex-direction:column;gap:2px}.move-row{display:grid;grid-template-columns:32px 1fr 1fr;gap:6px;align-items:center}.move-number{color:var(--text-muted);font-size:12px;text-align:right}.move-entry{padding:4px 8px;border-radius:4px;cursor:pointer;transition:var(--transition);overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.move-entry:hover{background:#ffffff0d}.move-entry.current{background:#d4af3726;color:var(--accent)}.move-entry.red{color:var(--red-piece-light)}.move-entry.black{color:var(--text-primary)}.move-entry.empty{cursor:default;opacity:0}.move-history-empty{text-align:center;color:var(--text-muted);padding:20px;font-size:13px}.captured-pieces{display:flex;flex-wrap:wrap;gap:4px;min-height:32px;align-items:center}.captured-piece{width:28px;height:28px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:14px;font-weight:700;background:radial-gradient(circle at 35% 35%,#f5e6c8,#e8d0a0);opacity:.7}.captured-piece.red{color:var(--red-piece);border:1px solid var(--red-piece)}.captured-piece.black{color:var(--black-piece);border:1px solid var(--black-piece)}.captured-empty{font-size:12px;color:var(--text-muted)}.modal-overlay{position:fixed;top:0;left:0;width:100%;height:100%;background:#000000b3;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);display:flex;align-items:center;justify-content:center;z-index:1000;padding:20px;animation:fadeIn .2s ease-out}.modal{background:var(--bg-secondary);border-radius:var(--radius);border:1px solid var(--border-color);padding:24px;max-width:480px;width:100%;max-height:85vh;max-height:85dvh;overflow-y:auto;box-shadow:0 20px 60px #00000080;animation:slideUp .3s ease-out}.modal-title{font-size:20px;font-weight:700;color:var(--accent);margin-bottom:16px;text-align:center}.modal-section{margin-bottom:20px}.modal-label{font-size:14px;font-weight:600;color:var(--text-secondary);margin-bottom:8px;display:block}.option-group{display:grid;grid-template-columns:repeat(auto-fit,minmax(80px,1fr));gap:8px}.option-btn{padding:12px 8px;border:2px solid 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0}.toggle-label{font-size:14px}.toggle{position:relative;width:44px;height:24px;background:#ffffff1a;border-radius:12px;cursor:pointer;transition:var(--transition)}.toggle.on{background:var(--accent)}.toggle:after{content:"";position:absolute;top:2px;left:2px;width:20px;height:20px;background:#fff;border-radius:50%;transition:var(--transition)}.toggle.on:after{left:22px}.setting-row{display:flex;align-items:center;justify-content:space-between;padding:8px 0;flex-wrap:wrap;gap:8px}.setting-label{font-size:14px}.setting-hint{width:100%;font-size:12px;color:var(--text-muted);margin-top:-4px;margin-bottom:4px}.difficulty-pills{display:flex;gap:4px}.pill{padding:4px 10px;font-size:12px;border:1px solid rgba(255,255,255,.15);background:transparent;color:var(--text-muted);border-radius:12px;cursor:pointer;transition:var(--transition)}.pill:hover{border-color:#ffffff4d;color:var(--text-primary)}.pill.active{background:var(--accent);border-color:var(--accent);color:#1a1a2e;font-weight:600}.layout-editor{display:flex;flex-direction:column;gap:12px}.piece-palette{display:grid;grid-template-columns:repeat(7,1fr);gap:6px}.palette-piece{aspect-ratio:1;border-radius:50%;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:1px;font-size:15px;font-weight:700;cursor:pointer;transition:var(--transition);background:radial-gradient(circle at 35% 35%,#f5e6c8,#e8d0a0);border:2px solid transparent;position:relative;line-height:1.1}.palette-piece .palette-count{font-size:10px;font-weight:600;opacity:.7}.palette-piece.red{color:var(--red-piece)}.palette-piece.black{color:var(--black-piece)}.palette-piece.selected{border-color:var(--accent);box-shadow:0 0 8px #d4af3780;transform:scale(1.1)}.palette-piece.disabled{opacity:.35;cursor:not-allowed;filter:grayscale(.4)}.palette-piece.tool-remove{border-radius:10px;font-size:13px;color:#e74c3c;border:2px dashed rgba(231,76,60,.5);background:#e74c3c1f}.palette-piece.tool-remove.selected{border-style:solid;border-color:#e74c3c;background:#e74c3c47;box-shadow:0 0 10px #e74c3c73}.palette-piece:hover:not(.disabled){transform:scale(1.05)}.game-over-overlay{position:absolute;top:0;left:0;width:100%;height:100%;background:#000000bf;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);display:flex;flex-direction:column;align-items:center;justify-content:center;z-index:50;border-radius:var(--radius);animation:fadeIn .3s ease-out}.game-over-title{font-size:clamp(28px,6vw,48px);font-weight:900;margin-bottom:8px;text-shadow:0 4px 20px rgba(0,0,0,.5)}.game-over-title.win{color:var(--accent-light)}.game-over-title.lose{color:var(--red-piece-light)}.game-over-subtitle{font-size:16px;color:var(--text-secondary);margin-bottom:24px}.ai-thinking{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--accent)}.thinking-dots{display:flex;gap:3px}.thinking-dot{width:6px;height:6px;border-radius:50%;background:var(--accent);animation:bounce 1.4s ease-in-out infinite}.thinking-dot:nth-child(2){animation-delay:.2s}.thinking-dot:nth-child(3){animation-delay:.4s}.check-fx{position:fixed;top:0;right:0;bottom:0;left:0;z-index:3000;pointer-events:none;display:flex;align-items:center;justify-content:center;overflow:hidden}.check-fx-flash{position:absolute;top:0;right:0;bottom:0;left:0;background:radial-gradient(circle at center,rgba(255,60,40,.45),transparent 55%);animation:checkFlash 1.5s ease-out forwards}.check-fx-ring,.check-fx-ring.delay{position:absolute;width:min(70vw,420px);height:min(70vw,420px);border-radius:50%;border:3px solid rgba(255,80,50,.85);box-shadow:0 0 30px #ff3c2880,inset 0 0 30px #ff503240;animation:checkRing 1.2s ease-out forwards}.check-fx-ring.delay{animation-delay:.15s;border-color:#ffc450b3}.check-fx-slash{position:absolute;width:min(90vw,560px);height:6px;background:linear-gradient(90deg,transparent,#ff3b2f,#ffd36a,#ff3b2f,transparent);box-shadow:0 0 20px #ff5028e6;transform:rotate(-18deg) scaleX(0);animation:checkSlash .7s cubic-bezier(.2,.8,.2,1) forwards}.check-fx-text{position:relative;display:flex;flex-direction:column;align-items:center;gap:6px;animation:checkTextPop 1.5s cubic-bezier(.2,1.4,.3,1) forwards;filter:drop-shadow(0 8px 24px rgba(0,0,0,.55))}.check-fx-main{font-size:clamp(48px,12vw,96px);font-weight:900;letter-spacing:.28em;color:#fff5e8;text-shadow:0 0 8px rgba(255,80,40,.95),0 0 24px rgba(255,40,20,.8),0 4px 0 #8b1a10,0 8px 18px rgba(0,0,0,.55);background:linear-gradient(180deg,#fff7e6,#ffb347 45%,#ff3b2f);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;padding-left:.28em}.check-fx-sub{font-size:clamp(12px,2.5vw,18px);font-weight:800;letter-spacing:.55em;color:#ffd2a0e6;text-shadow:0 0 12px rgba(255,80,40,.7);padding-left:.55em}@keyframes checkFlash{0%{opacity:0}12%{opacity:1}40%{opacity:.55}to{opacity:0}}@keyframes checkRing{0%{transform:scale(.2);opacity:.95}70%{opacity:.45}to{transform:scale(1.35);opacity:0}}@keyframes checkSlash{0%{transform:rotate(-18deg) scaleX(0);opacity:0}30%{opacity:1}55%{transform:rotate(-18deg) scaleX(1);opacity:1}to{transform:rotate(-18deg) scaleX(1.05);opacity:0}}@keyframes checkTextPop{0%{transform:scale(.2) rotate(-8deg);opacity:0}25%{transform:scale(1.18) rotate(2deg);opacity:1}45%{transform:scale(.96) rotate(-1deg)}65%{transform:scale(1.05) rotate(0)}85%{opacity:1}to{transform:scale(1.1);opacity:0}}@keyframes checkSquarePulse{0%,to{transform:scale(1);opacity:1}50%{transform:scale(1.15);opacity:.7}}@keyframes checkPieceShake{0%,to{transform:translate(0) scale(1.08)}25%{transform:translate(-3px) scale(1.12)}75%{transform:translate(3px) scale(1.12)}}.toast{position:fixed;top:70px;left:50%;transform:translate(-50%);padding:12px 28px;background:var(--bg-secondary);border:1px solid var(--accent);border-radius:var(--radius-sm);color:var(--text-primary);font-size:15px;font-weight:600;letter-spacing:.02em;z-index:2000;box-shadow:var(--shadow);animation:toastIn .3s ease-out}.toast.capture{border-color:#e74c3c;background:linear-gradient(135deg,rgba(231,76,60,.25),var(--bg-secondary));color:#ffd7d2;font-size:16px;box-shadow:0 0 20px #e74c3c59}.toast.check{border-color:#e67e22;background:linear-gradient(135deg,rgba(230,126,34,.28),var(--bg-secondary));color:#ffe0c2;font-size:17px;box-shadow:0 0 20px #e67e2266}.toast.hint{border-color:#3498db;background:linear-gradient(135deg,rgba(52,152,219,.3),var(--bg-secondary));color:#d6ecff;font-size:16px;box-shadow:0 0 20px #3498db66}.move-arrow-line{stroke:#e67e22d9;stroke-width:.08;stroke-linecap:round;pointer-events:none}.hint-arrow-line{stroke:#3498dbf2;stroke-width:.1;stroke-linecap:round;stroke-dasharray:.25 .12;pointer-events:none;animation:hintArrowPulse 1s ease-in-out infinite}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes slideUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes pulse{0%,to{opacity:1}50%{opacity:.5}}@keyframes pieceMove{0%{transform:scale(1.2)}to{transform:scale(1)}}@keyframes pieceCapture{0%{transform:scale(1);opacity:1}60%{transform:scale(.85);opacity:.6}to{transform:scale(.2);opacity:0}}@keyframes capturePulse{0%,to{transform:scale(1);opacity:1}50%{transform:scale(1.08);opacity:.75}}@keyframes lastMoveFlash{0%{transform:scale(1.25);opacity:1}to{transform:scale(1);opacity:1}}@keyframes hintPulse{0%,to{opacity:1;transform:scale(1)}50%{opacity:.7;transform:scale(1.12)}}@keyframes hintPiecePulse{0%,to{transform:scale(1.12)}50%{transform:scale(1.2)}}@keyframes hintArrowPulse{0%,to{opacity:1}50%{opacity:.55}}@keyframes bounce{0%,80%,to{transform:scale(0)}40%{transform:scale(1)}}@keyframes toastIn{0%{opacity:0;transform:translate(-50%) translateY(-10px)}to{opacity:1;transform:translate(-50%) translateY(0)}}@media(max-width:768px){.main-content{flex-direction:column;padding:0;gap:0}.board-wrapper{max-width:100%;width:100vw}.board-area{padding:4px;align-items:stretch}.side-panel{width:100%;max-height:none;overflow-y:visible;padding:8px}.app-header{padding:8px 12px}.app-title{font-size:16px}.panel-card{padding:10px}.move-history{max-height:200px}.player-bar{padding:8px 12px}.player-avatar{width:32px;height:32px;font-size:16px}.player-name{font-size:13px}.player-timer{font-size:16px}.btn{padding:8px 12px;font-size:13px}.modal{padding:16px;margin:10px}.modal-title{font-size:18px}}@media(max-width:400px){.app-title{font-size:14px;letter-spacing:1px}.btn{padding:6px 10px;font-size:12px}}@media(max-width:360px){.piece{font-size:14px}}@media(max-height:500px)and (orientation:landscape){.main-content{flex-direction:row;padding:4px}.board-wrapper{max-width:50vh}.side-panel{width:280px;max-height:calc(100vh - 60px)}}.app-footer{display:flex;align-items:center;justify-content:center;gap:10px;padding:10px 16px;background:#0f0f1ae6;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-top:1px solid var(--border-color);font-size:12px;color:var(--text-muted);flex-shrink:0}.app-footer .footer-text{letter-spacing:.5px}.app-footer .footer-link{display:inline-flex;align-items:center;gap:5px;color:var(--text-secondary);text-decoration:none;transition:var(--transition)}.app-footer .footer-link:hover{color:var(--accent-light)}.app-footer .footer-github-icon{flex-shrink:0}@media(max-width:768px){.app-footer{padding:8px 12px;font-size:11px;flex-wrap:wrap;gap:6px}}