:root{--bg-color:#121212;--bg-gradient:linear-gradient(135deg, #1e1e1e 0%, #121212 100%);--panel-bg:#1e1e1ee6;--panel-border:#ffffff1a;--text-main:#f8fafc;--text-muted:#94a3b8;--accent-primary:#3b82f6;--accent-secondary:#2563eb;--accent-hover:#1d4ed8;--danger:#ef4444;--white-turn:#e2e8f0;--black-turn:#94a3b8;--board-bg:#2a2a2a}[data-theme=light]{--bg-color:#f8fafc;--bg-gradient:linear-gradient(135deg, #e2e8f0 0%, #f8fafc 100%);--panel-bg:#ffffffe6;--panel-border:#0000001a;--text-main:#0f172a;--text-muted:#475569;--accent-primary:#2563eb;--accent-secondary:#1d4ed8;--accent-hover:#1e3a8a;--white-turn:#0f172a;--black-turn:#64748b;--board-bg:#e2e8f0}*{box-sizing:border-box}body{background:var(--bg-gradient);background-color:var(--bg-color);color:var(--text-main);justify-content:center;align-items:center;min-height:100vh;margin:0;padding:0;font-family:Inter,system-ui,sans-serif;transition:background .3s,color .3s;display:flex;overflow:hidden auto}#app{flex-direction:row;justify-content:center;align-items:flex-start;gap:3rem;width:100%;max-width:1400px;height:auto;min-height:90vh;padding:2rem;display:flex;position:relative}#game-container{border:1px solid var(--panel-border);background:var(--board-bg);aspect-ratio:1;border-radius:12px;flex-shrink:0;width:100%;max-width:720px;height:auto;position:relative;box-shadow:0 10px 30px #0000004d}#ui-panel{background:var(--panel-bg);border:1px solid var(--panel-border);border-radius:12px;flex-direction:column;gap:1rem;width:400px;height:720px;padding:1.5rem;transition:background .3s,border .3s;display:flex;overflow:hidden;box-shadow:0 10px 30px #0000001a}@media (width<=1200px){#app{flex-direction:column;align-items:center;gap:1.5rem;padding:1rem}#ui-panel{width:100%;max-width:720px;height:auto;min-height:500px}body{align-items:flex-start}}.panel-header{border-bottom:1px solid var(--panel-border);justify-content:space-between;align-items:center;padding-bottom:1rem;display:flex}h1{letter-spacing:-.02em;margin:0;font-size:2.2rem;font-weight:800}#turn-indicator{text-transform:uppercase;letter-spacing:.05em;border-radius:6px;padding:.4rem .8rem;font-size:.9rem;font-weight:700;transition:all .3s}#turn-indicator[data-turn=white]{color:var(--text-main);border:1px solid var(--panel-border);background:#64748b1a}#turn-indicator[data-turn=black]{color:var(--text-muted);border:1px solid var(--panel-border);background:#64748b1a}.timers{justify-content:space-between;gap:1rem;display:flex}.clock{text-align:center;border:1px solid var(--panel-border);color:var(--text-main);background:#64748b1a;border-radius:6px;flex:1;padding:.5rem;font-family:monospace;font-size:1.5rem;font-weight:700}.clock.active{background:var(--accent-primary);color:#fff;border-color:var(--accent-secondary)}.panel-section{flex-direction:column;flex-grow:1;min-height:0;display:flex;overflow:hidden}.panel-section.elo-section{flex-grow:0;flex-shrink:0;min-height:auto;overflow:visible}h2{color:var(--text-muted);text-transform:uppercase;letter-spacing:.05em;white-space:nowrap;margin:0 0 .6rem;font-size:.85rem;font-weight:700}#xtra-rules-panel{flex-direction:column;gap:.8rem;padding-right:.5rem;display:flex;overflow-y:auto}#xtra-rules-panel::-webkit-scrollbar{width:6px}#xtra-rules-panel::-webkit-scrollbar-track{background:#64748b1a;border-radius:3px}#xtra-rules-panel::-webkit-scrollbar-thumb{background:#64748b4d;border-radius:3px}.rule-card{border:1px solid var(--panel-border);background-color:#64748b0d;border-radius:8px;align-items:flex-start;gap:1rem;padding:1rem;transition:all .2s;display:flex}.rule-card.rule-active{border-color:var(--accent-primary);background-color:#3b82f60d}.switch{flex-shrink:0;width:44px;height:24px;margin-top:.2rem;display:inline-block;position:relative}.switch input{opacity:0;width:0;height:0}.slider{cursor:pointer;background-color:#64748b4d;border-radius:34px;transition:all .3s;position:absolute;inset:0}.slider:before{content:"";background-color:#fff;border-radius:50%;width:18px;height:18px;transition:all .3s;position:absolute;bottom:3px;left:3px;box-shadow:0 2px 4px #0003}input:checked+.slider{background-color:var(--accent-primary)}input:checked+.slider:before{transform:translate(20px)}.rule-info{flex-direction:column;gap:.3rem;display:flex}.rule-name{color:var(--text-main);align-items:center;gap:.4rem;font-size:1.05rem;font-weight:600;display:flex}.rule-emoji{font-size:1.2rem;line-height:1}.rule-desc{color:var(--text-muted);font-size:.85rem;line-height:1.4}.rule-flavour{color:var(--accent-primary);margin-top:.2rem;font-size:.75rem;font-style:italic}button{background:var(--accent-primary);color:#fff;cursor:pointer;text-transform:uppercase;letter-spacing:.05em;border:none;border-radius:8px;margin-top:auto;padding:1rem;font-size:1rem;font-weight:600;transition:background .2s}button:hover{background:var(--accent-hover)}#start-overlay{-webkit-backdrop-filter:blur(16px);z-index:1000;text-align:center;background:#0f172abf;border-radius:12px;flex-direction:column;justify-content:center;align-items:center;display:flex;position:absolute;inset:0}#start-overlay h1{margin-bottom:.5rem;font-size:3rem}#start-overlay p{color:var(--text-muted);margin-bottom:2rem}.start-buttons{gap:1rem;display:flex}.start-buttons button{min-width:150px}#game-toast{z-index:9999;-webkit-backdrop-filter:blur(24px);pointer-events:all;background:linear-gradient(135deg,#0f172af5 0%,#1e143cf5 100%);border:1px solid #8b5cf68c;border-radius:18px;align-items:center;gap:1rem;min-width:300px;max-width:420px;padding:1.1rem 1.5rem;transition:top .52s cubic-bezier(.175,.885,.32,1.275);display:flex;position:fixed;top:-140px;left:50%;transform:translate(-50%);box-shadow:0 24px 64px #0000008c,0 0 40px #8b5cf62e,inset 0 1px #ffffff14}#game-toast.toast-visible{top:1.5rem}.toast-icon{filter:drop-shadow(0 2px 8px #00000080);font-size:2.2rem;line-height:1;animation:none}#game-toast.toast-visible .toast-icon{animation:.5s cubic-bezier(.175,.885,.32,1.275) .35s both toast-pop}.toast-content{flex:1;min-width:0}.toast-title{text-transform:uppercase;letter-spacing:.18em;opacity:.9;margin-bottom:.15rem;font-size:.72rem;font-weight:700}.toast-subtitle{color:#f8fafc;letter-spacing:-.01em;white-space:nowrap;font-size:1.45rem;font-weight:800;line-height:1.1}.toast-close{color:#ffffff8c;cursor:pointer;text-transform:none;letter-spacing:0;background:#ffffff14;border:1px solid #ffffff2e;border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:30px;min-width:30px;height:30px;margin:0;padding:0;font-size:.78rem;font-weight:400;transition:background .2s,color .2s,border-color .2s;display:flex}.toast-close:hover{color:#fff;background:#ffffff2e;border-color:#fff6}@keyframes toast-pop{0%{opacity:0;transform:scale(.4)rotate(-15deg)}70%{transform:scale(1.25)rotate(5deg)}to{opacity:1;transform:scale(1)rotate(0)}}.header-controls{align-items:center;gap:1rem;display:flex}.icon-btn{border:1px solid var(--panel-border);width:36px;height:36px;color:var(--text-main);background:0 0;border-radius:6px;justify-content:center;align-items:center;margin:0;padding:0;font-size:1.1rem;display:flex}.icon-btn:hover{background:#64748b1a}.elo-header{flex-wrap:nowrap;justify-content:space-between;align-items:center;gap:.5rem;margin-bottom:.5rem;display:flex}.elo-header h2{white-space:nowrap;flex-shrink:0;margin:0}#elo-display{color:var(--accent-primary);white-space:nowrap;background:#64748b1f;border-radius:4px;padding:.2rem .6rem;font-size:1rem;font-weight:800}#elo-tier{white-space:nowrap;flex-shrink:0}.elo-slider{-webkit-appearance:none;cursor:pointer;background:#64748b33;border-radius:4px;outline:none;width:100%;height:8px;margin:0;transition:height .15s}.elo-slider:hover{height:10px}.elo-slider::-webkit-slider-thumb{appearance:none;background:var(--accent-primary);cursor:pointer;border:2px solid #fff3;border-radius:50%;width:20px;height:20px;transition:transform .15s;box-shadow:0 2px 8px #0000004d}.elo-slider::-webkit-slider-thumb:hover{transform:scale(1.2)}.promotion-modal{z-index:8000;-webkit-backdrop-filter:blur(12px);opacity:0;pointer-events:none;background:#000000b8;justify-content:center;align-items:center;transition:opacity .25s;display:flex;position:fixed;inset:0}.promotion-modal.modal-visible{opacity:1;pointer-events:all}.promotion-modal-inner{text-align:center;background:linear-gradient(145deg,#141423f7 0%,#1e1937f7 100%);border:1px solid #8b5cf680;border-radius:20px;padding:2rem 2.5rem;transition:transform .28s cubic-bezier(.175,.885,.32,1.275);transform:scale(.88);box-shadow:0 30px 80px #0009,0 0 60px #8b5cf626,inset 0 1px #ffffff14}.promotion-modal.modal-visible .promotion-modal-inner{transform:scale(1)}.promo-title{text-transform:uppercase;letter-spacing:.14em;color:#a78bfad9;margin:0 0 1.4rem;font-size:.75rem;font-weight:700}.promo-options{gap:1rem;display:flex}.promo-option{cursor:pointer;text-transform:none;letter-spacing:0;background:#ffffff0a;border:1px solid #ffffff1f;border-radius:14px;flex-direction:column;align-items:center;gap:.4rem;min-width:80px;margin:0;padding:1.2rem 1rem;transition:background .18s,border-color .18s,transform .14s,box-shadow .18s;display:flex}.promo-option:hover{background:#8b5cf633;border-color:#8b5cf6b3;transform:translateY(-3px)scale(1.04);box-shadow:0 8px 24px #8b5cf64d}.promo-icon{font-size:2.6rem;line-height:1}.promo-label{text-transform:uppercase;letter-spacing:.06em;color:var(--text-muted);font-size:.72rem;font-weight:600}