.square{display:flex;align-items:center;justify-content:center;border:none;outline:none;position:relative;-webkit-user-select:none;user-select:none;padding:8%;min-width:0;min-height:0;overflow:hidden}.square--light{background:var(--sq-light)}.square--dark{background:var(--sq-dark)}.square.square--visited.square--light{background:var(--sq-visited-light)}.square.square--visited.square--dark{background:var(--sq-visited-dark)}.square.square--current{background:var(--sq-current)}.square.square--valid{cursor:pointer;background:var(--sq-valid-highlight)}.square.square--valid:hover{filter:brightness(1.15)}.square.square--hint{background:var(--sq-hint-highlight)}.square--idle{cursor:pointer}.square--idle:hover{filter:brightness(1.1)}.square__knight{width:100%;height:100%;filter:drop-shadow(0 2px 3px rgba(0,0,0,.4));animation:knight-land .25s ease-out}.square__number{display:flex;align-items:center;justify-content:center;width:clamp(16px,65%,40px);height:clamp(16px,65%,40px);border-radius:50%;background:var(--num-bg);color:var(--num-color);font-size:clamp(.5rem,calc(2.2vmin / var(--board-size) * 4),.9rem);font-weight:700;font-variant-numeric:tabular-nums;letter-spacing:-.02em;line-height:1;opacity:.65;-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px);box-shadow:0 1px 3px #0003}.square__number--recent{opacity:1;box-shadow:0 1px 6px #00000059}@keyframes knight-land{0%{transform:scale(.5);opacity:.3}60%{transform:scale(1.08)}to{transform:scale(1);opacity:1}}.board{display:grid;grid-template-columns:repeat(var(--board-size),1fr);grid-template-rows:repeat(var(--board-size),1fr);width:clamp(260px,60vmin,520px);height:clamp(260px,60vmin,520px);border-radius:var(--radius);overflow:hidden;box-shadow:0 8px 32px #00000080,0 0 0 2px #ffffff0f;flex-shrink:0;background:var(--sq-dark)}.size-selector{display:flex;flex-direction:column;gap:.6rem}.size-selector__label{font-size:.85rem;color:var(--text-dim);text-transform:uppercase;letter-spacing:.1em}.size-selector__options{display:flex;gap:.35rem;flex-wrap:wrap}.size-selector__btn{width:2.4rem;height:2.4rem;border-radius:var(--radius);background:var(--bg-surface);border:1px solid rgba(255,255,255,.08);font-size:.85rem;font-weight:600;transition:background var(--transition),border-color var(--transition),transform var(--transition)}.size-selector__btn:hover{background:var(--bg-elevated);border-color:var(--accent);transform:translateY(-2px)}.size-selector__btn--active{background:var(--accent);color:#fff;border-color:var(--accent)}.size-selector__btn--active:hover{background:var(--accent);filter:brightness(1.15)}.theme-selector{display:flex;flex-direction:column;gap:.6rem}.theme-selector__label{font-size:.75rem;color:var(--text-dim);text-transform:uppercase;letter-spacing:.1em}.theme-selector__options{display:flex;gap:.4rem;flex-wrap:wrap}.theme-swatch{width:2rem;height:2rem;border-radius:6px;border:2px solid transparent;overflow:hidden;display:grid;grid-template-columns:1fr 1fr;grid-template-rows:1fr 1fr;transition:border-color var(--transition),transform var(--transition),box-shadow var(--transition);cursor:pointer}.theme-swatch:hover{transform:scale(1.12);border-color:#ffffff4d}.theme-swatch--active{border-color:var(--accent);box-shadow:0 0 8px var(--accent-glow)}.theme-swatch__quadrant{width:100%;height:100%}.controls{display:flex;gap:.5rem;flex-wrap:wrap}.controls__btn{padding:.6rem 1.2rem;border-radius:var(--radius);font-size:.85rem;font-weight:600;transition:background var(--transition),border-color var(--transition),transform var(--transition);border:1px solid rgba(255,255,255,.08);background:var(--bg-surface)}.controls__btn:hover:not(:disabled){background:var(--bg-elevated);border-color:#ffffff26;transform:translateY(-1px)}.controls__btn:disabled{opacity:.35;cursor:not-allowed}.controls__btn--reset{border-color:var(--danger);color:var(--danger)}.controls__btn--reset:hover:not(:disabled){background:#ef53501a}.controls__btn--quit{border-color:var(--text-dim);color:var(--text-dim)}.controls__btn--quit:hover:not(:disabled){background:#8a8a9a1a}.game-status{display:flex;flex-direction:column;gap:1rem}.game-status__title{font-size:1.6rem;font-weight:800;letter-spacing:-.02em}.game-status__title span{opacity:.4;font-weight:400}.game-status__phase{font-size:.95rem;padding:.5rem .8rem;border-radius:var(--radius);font-weight:600}.game-status__phase--idle{background:#6c8aff1a;color:var(--accent)}.game-status__phase--playing{background:#4caf501a;color:var(--success)}.game-status__phase--won{background:#4caf5026;color:var(--success);animation:won-glow 2s ease-in-out infinite}.game-status__phase--stuck{background:#ef53501f;color:var(--danger)}.game-status__timer{font-size:1.8rem;font-weight:700;font-variant-numeric:tabular-nums;letter-spacing:.04em;color:var(--accent)}.game-status__progress{display:flex;flex-direction:column;gap:.4rem}.game-status__progress-label{display:flex;justify-content:space-between;font-size:.8rem;color:var(--text-dim)}.game-status__progress-bar{height:6px;border-radius:3px;background:var(--bg-elevated);overflow:hidden}.game-status__progress-fill{height:100%;border-radius:3px;background:var(--accent);transition:width .3s ease}.game-status__progress-fill--won{background:var(--success)}.game-status__rules{font-size:.8rem;color:var(--text-dim);line-height:1.6}.game-status__rules p{margin-bottom:.3rem}@keyframes won-glow{0%,to{box-shadow:0 0 8px #4caf5033}50%{box-shadow:0 0 20px #4caf5066}}.leaderboard{width:100%}.leaderboard__title{font-size:1rem;font-weight:700;margin-bottom:.75rem;color:var(--text)}.leaderboard__table{width:100%;border-collapse:collapse;font-size:.85rem;font-variant-numeric:tabular-nums}.leaderboard__table th{text-align:left;color:var(--text-dim);font-weight:600;padding:.4rem .6rem;border-bottom:1px solid rgba(255,255,255,.08)}.leaderboard__table th:first-child{width:2rem;text-align:center}.leaderboard__table th:last-child{text-align:right}.leaderboard__table td{padding:.4rem .6rem;border-bottom:1px solid rgba(255,255,255,.04)}.leaderboard__table td:first-child{text-align:center;color:var(--text-dim)}.leaderboard__table td:last-child{text-align:right;font-weight:600}.leaderboard__row--highlight{background:#6c8aff1f}.leaderboard__row--highlight td{color:var(--accent)}.win-modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#000000b3;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);display:flex;align-items:center;justify-content:center;z-index:100;padding:1rem}.win-modal{background:var(--bg-surface);border:1px solid rgba(255,255,255,.08);border-radius:12px;padding:2rem;max-width:380px;width:100%;position:relative;animation:modal-enter .25s ease-out}.win-modal__close{position:absolute;top:.75rem;right:.75rem;font-size:1.4rem;color:var(--text-dim);line-height:1;padding:.25rem}.win-modal__close:hover{color:var(--text)}.win-modal__title{font-size:1.4rem;font-weight:800;color:var(--success);margin-bottom:.5rem}.win-modal__time{font-size:2.2rem;font-weight:700;font-variant-numeric:tabular-nums;letter-spacing:.04em;color:var(--accent);margin-bottom:.25rem}.win-modal__board{font-size:.85rem;color:var(--text-dim);margin-bottom:1.5rem}.win-modal__form{display:flex;flex-direction:column;gap:.75rem}.win-modal__input{padding:.7rem 1rem;border-radius:var(--radius);border:1px solid rgba(255,255,255,.1);background:var(--bg-elevated);color:var(--text);font-size:.95rem;font-family:inherit;outline:none;transition:border-color var(--transition)}.win-modal__input:focus{border-color:var(--accent)}.win-modal__input::placeholder{color:var(--text-dim)}.win-modal__submit{padding:.7rem 1.2rem;border-radius:var(--radius);font-size:.9rem;font-weight:600;background:var(--accent);color:#fff;transition:background var(--transition),transform var(--transition)}.win-modal__submit:hover:not(:disabled){background:#5a78ee;transform:translateY(-1px)}.win-modal__submit:disabled{opacity:.4;cursor:not-allowed}@keyframes modal-enter{0%{opacity:0;transform:scale(.95) translateY(8px)}to{opacity:1;transform:scale(1) translateY(0)}}.app{display:flex;gap:2.5rem;align-items:flex-start;max-width:900px;width:100%}.app__sidebar{display:flex;flex-direction:column;gap:1.5rem;min-width:200px;flex:1}@media(max-width:640px){.app{flex-direction:column;align-items:center;gap:1.5rem}.app__sidebar{width:100%;align-items:center;text-align:center}.controls{justify-content:center}}*,*:before,*:after{margin:0;padding:0;box-sizing:border-box}:root{--bg: #0f0f14;--bg-surface: #1a1a24;--bg-elevated: #24243a;--text: #e8e6e3;--text-dim: #8a8a9a;--accent: #6c8aff;--accent-glow: rgba(108, 138, 255, .25);--success: #4caf50;--warning: #ff9800;--danger: #ef5350;--board-size: 8;--radius: 8px;--transition: .15s ease;color-scheme:dark}html,body{height:100%}body{font-family:Inter,system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text);-webkit-font-smoothing:antialiased}#root{min-height:100%;display:flex;align-items:center;justify-content:center;padding:1.5rem}button{font-family:inherit;cursor:pointer;border:none;background:none;color:inherit}