:root{color-scheme:light;--brand-from: #667eea;--brand-to: #764ba2;--brand-gradient: linear-gradient(135deg, var(--brand-from) 0%, var(--brand-to) 100%);--app-bg: linear-gradient(160deg, #f0f2ff 0%, #e8ecf8 55%, #dde3f5 100%);--surface: #ffffff;--surface-muted: #f8fafc;--surface-hover: #f1f5f9;--surface-active: #e8e8e8;--border-subtle: #e2e8f0;--border-strong: #cbd5e1;--nav-hover-bg: rgba(255, 255, 255, .7);--modal-backdrop: rgba(0, 0, 0, .55);--text-primary: #1a2332;--text-secondary: #4a5568;--text-muted: #94a3b8;--font-sans: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;--accent: #1976d2;--accent-hover: #1565c0;--board-border: #333;--board-bg: #f5f5f5;--bank-border: #ddd;--bank-bg: #fafafa;--cell-dashed-border: #ccc;--cell-occupied-border: #4CAF50;--cell-occupied-bg: #e8f5e8;--cell-completed-border: #888;--cell-completed-bg: #e0e0e0;--cell-disabled-border: #666;--cell-disabled-bg: #333;--cell-disabled-spot: #444;--cell-disabled-dot: #666;--center-indicator-bg: #666;--center-indicator-border: #888;--preview-corner-border: #666;--select-color: #FF9800;--select-bg: #fff3e0;--drag-color: #2196F3;--drag-bg: #e3f2fd;--drop-target-bg: rgba(227, 242, 253, .5);--error-accent: #f44336;--error-text: #c62828;--error-bg: #ffebee;--error-border: #ef9a9a;--success-text: #2e7d32;--success-border: #c8e6c9;--info-bg: #e3f2fd;--info-text: #1565c0;--info-border: #90caf9;--tag-bg: #eceff1;--tag-text: #455a64;--tag-success-bg: #dcedc8;--tag-success-text: #33691e;--btn-secondary-bg: #f0f0f0;--btn-secondary-hover: #e0e0e0;--track-bg: #eee;--toast-bg: #37474f;--toast-text: #fff;--streak-border: #ffcc80;--streak-bg: #fff8e1;--streak-text: #e65100;--streak-hover-bg: #fff3e0;--shimmer-a: #e8edf2;--shimmer-b: #f8fafc;--skeleton-strong: #e0e0e0;--difficulty-1-color: #F9A825;--difficulty-1-bg: #FFF9C4;--difficulty-1-accent: #F57F17;--difficulty-1-glow: 249, 168, 37;--difficulty-2-color: #2E7D32;--difficulty-2-bg: #C8E6C9;--difficulty-2-accent: #4CAF50;--difficulty-2-glow: 76, 175, 80;--difficulty-3-color: #1565C0;--difficulty-3-bg: #BBDEFB;--difficulty-3-accent: #42A5F5;--difficulty-3-glow: 21, 101, 192;--difficulty-4-color: #6A1B9A;--difficulty-4-bg: #E1BEE7;--difficulty-4-accent: #AB47BC;--difficulty-4-glow: 106, 27, 154;--difficulty-easy-color: var(--difficulty-2-color);--difficulty-medium-color: var(--difficulty-3-color);--difficulty-hard-color: var(--difficulty-4-color)}:root[data-theme=dark]{color-scheme:dark;--app-bg: linear-gradient(160deg, #10141f 0%, #131828 55%, #171d30 100%);--surface: #1e2536;--surface-muted: #252e44;--surface-hover: #2b3550;--surface-active: #333e5c;--border-subtle: #36415c;--border-strong: #47536e;--nav-hover-bg: rgba(255, 255, 255, .08);--modal-backdrop: rgba(0, 0, 0, .7);--text-primary: #e8ecf5;--text-secondary: #aeb9cc;--text-muted: #7b869e;--board-border: #4a5570;--board-bg: #1a2132;--bank-border: #36415c;--bank-bg: #1a2132;--cell-dashed-border: #3e4a66;--cell-occupied-bg: #1d3323;--cell-completed-border: #5a657f;--cell-completed-bg: #2c3650;--cell-disabled-border: #2a3348;--cell-disabled-bg: #141a29;--cell-disabled-spot: #1c2338;--cell-disabled-dot: #333e58;--center-indicator-bg: #57627e;--center-indicator-border: #727e9c;--preview-corner-border: #8090ad;--select-bg: #3d2c10;--drag-bg: #14304d;--drop-target-bg: rgba(33, 101, 181, .25);--error-accent: #ef5350;--error-text: #ef9a9a;--error-bg: #3a1f22;--error-border: #6e3038;--success-text: #81c784;--success-border: #2e5233;--info-bg: #14304d;--info-text: #90caf9;--info-border: #1e4976;--tag-bg: #2b3550;--tag-text: #aeb9cc;--tag-success-bg: #234527;--tag-success-text: #a5d6a7;--btn-secondary-bg: #2b3550;--btn-secondary-hover: #333e5c;--track-bg: #2b3550;--toast-bg: #3a4560;--streak-border: #6e4a1a;--streak-bg: #33260e;--streak-text: #ffb74d;--streak-hover-bg: #3d2e12;--shimmer-a: #232c42;--shimmer-b: #2c374f;--skeleton-strong: #2c3650;--difficulty-1-color: #FBC02D;--difficulty-1-bg: #4a3f10;--difficulty-2-color: #43A047;--difficulty-2-bg: #1d3b20;--difficulty-3-color: #1E88E5;--difficulty-3-bg: #12325a;--difficulty-4-color: #8E24AA;--difficulty-4-bg: #3a1b52}@media (prefers-color-scheme: dark){:root:not([data-theme=light]){color-scheme:dark;--app-bg: linear-gradient(160deg, #10141f 0%, #131828 55%, #171d30 100%);--surface: #1e2536;--surface-muted: #252e44;--surface-hover: #2b3550;--surface-active: #333e5c;--border-subtle: #36415c;--border-strong: #47536e;--nav-hover-bg: rgba(255, 255, 255, .08);--modal-backdrop: rgba(0, 0, 0, .7);--text-primary: #e8ecf5;--text-secondary: #aeb9cc;--text-muted: #7b869e;--board-border: #4a5570;--board-bg: #1a2132;--bank-border: #36415c;--bank-bg: #1a2132;--cell-dashed-border: #3e4a66;--cell-occupied-bg: #1d3323;--cell-completed-border: #5a657f;--cell-completed-bg: #2c3650;--cell-disabled-border: #2a3348;--cell-disabled-bg: #141a29;--cell-disabled-spot: #1c2338;--cell-disabled-dot: #333e58;--center-indicator-bg: #57627e;--center-indicator-border: #727e9c;--preview-corner-border: #8090ad;--select-bg: #3d2c10;--drag-bg: #14304d;--drop-target-bg: rgba(33, 101, 181, .25);--error-accent: #ef5350;--error-text: #ef9a9a;--error-bg: #3a1f22;--error-border: #6e3038;--success-text: #81c784;--success-border: #2e5233;--info-bg: #14304d;--info-text: #90caf9;--info-border: #1e4976;--tag-bg: #2b3550;--tag-text: #aeb9cc;--tag-success-bg: #234527;--tag-success-text: #a5d6a7;--btn-secondary-bg: #2b3550;--btn-secondary-hover: #333e5c;--track-bg: #2b3550;--toast-bg: #3a4560;--streak-border: #6e4a1a;--streak-bg: #33260e;--streak-text: #ffb74d;--streak-hover-bg: #3d2e12;--shimmer-a: #232c42;--shimmer-b: #2c374f;--skeleton-strong: #2c3650;--difficulty-1-color: #FBC02D;--difficulty-1-bg: #4a3f10;--difficulty-2-color: #43A047;--difficulty-2-bg: #1d3b20;--difficulty-3-color: #1E88E5;--difficulty-3-bg: #12325a;--difficulty-4-color: #8E24AA;--difficulty-4-bg: #3a1b52}}*,*:before,*:after{box-sizing:border-box}html,body{height:100%;margin:0;padding:0;overflow:hidden;font-family:var(--font-sans);color:var(--text-primary);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}button{font-family:inherit;transition:transform .12s ease,opacity .15s ease,background-color .15s ease,border-color .15s ease,box-shadow .15s ease}button:not(:disabled):active{transform:scale(.96)}button:focus-visible,a:focus-visible,select:focus-visible,input:focus-visible,textarea:focus-visible,[role=button]:focus-visible{outline:2px solid var(--brand-from);outline-offset:2px}@keyframes route-enter{0%{opacity:0;transform:translateY(6px)}to{opacity:1;transform:translateY(0)}}app-game-board,app-library,app-submit-puzzle{display:block;animation:route-enter .22s ease}@media (prefers-reduced-motion: reduce){*,*:before,*:after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}