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rgba(27,35,64,.22);display:grid;grid-template-columns:repeat(8,1fr);grid-template-rows:repeat(8,1fr);overflow:hidden;transform:rotate(-2deg);transition:transform .2s ease}.cs-hero-board:focus-visible .cs-board,.cs-hero-board:hover .cs-board{transform:rotate(0deg)}.cs-sq{background:var(--cs-sq-light);display:flex;min-height:0;min-width:0}.cs-sq-dark{background:var(--cs-sq-dark)}.cs-sq img{height:100%;width:100%}.cs-board-caption{color:var(--cs-ink-soft);display:flex;flex-direction:column;font-size:1.5rem;margin-top:1.6rem}.cs-board-caption strong{color:var(--cs-ink);font-size:1.7rem}.cs-stages>h2{font-size:3.4rem;font-weight:800;margin-bottom:2.4rem}.cs-book-meta{color:var(--cs-ink-soft);font-size:1.6rem;margin-bottom:2.8rem}.cs-stage-grid{display:grid;gap:3.2rem;grid-template-columns:repeat(3,minmax(0,1fr))}.cs-stage h3{font-size:2.4rem;font-weight:700;margin-bottom:.4rem}.cs-stage-text{color:var(--cs-ink-soft);font-size:1.5rem;line-height:1.45;margin-bottom:1.2rem;min-height:4.4em}.cs-chapter-list{list-style:none;margin:0;padding:0}.cs-chapter-list li{display:flex;margin:0 0 .8rem}.cs-chapter{align-items:center;background:var(--cs-card);border:1px solid var(--cs-line);border-inline-start:5px solid var(--cs-sq-dark);border-radius:6px;color:var(--cs-ink);display:grid;flex:1;gap:.4rem 1.2rem;grid-template-columns:1fr auto;padding:1.2rem 1.4rem;text-decoration:none}.cs-chapter:hover{border-color:var(--cs-ink-soft);border-inline-start-color:var(--cs-sun)}.cs-chapter-complete{border-inline-start-color:var(--cs-solved)}.cs-chapter-name{font-size:1.6rem;font-weight:700;line-height:1.3}.cs-chapter-group{color:var(--cs-ink-soft);display:block;font-size:1.3rem;font-weight:400}.cs-chapter-count{color:var(--cs-ink-soft);font-size:1.4rem;font-variant-numeric:tabular-nums}.cs-meter{background:var(--cs-sq-light);border-radius:3px;grid-column:1/-1;height:.6rem;overflow:hidden}.cs-meter>span{background:var(--cs-solved);display:block;height:100%}.cs-random{align-items:center;background:var(--cs-ink);border-radius:12px;color:var(--cs-paper);display:grid;gap:2.4rem;grid-template-columns:minmax(0,1fr) minmax(0,1.4fr);margin-bottom:5.6rem;padding:2.4rem}[data-theme=dark] .cs-random{background:#0e0e1c;border:1px solid var(--cs-line)}.cs-random h2{color:#fff;font-size:3rem;font-weight:800;margin-bottom:.6rem}.cs-random p{color:#c9d2e6;font-size:1.6rem;margin:0}.cs-random-buttons{display:grid;gap:1rem;grid-template-columns:repeat(3,minmax(0,1fr))}.cs-random-button{background:var(--cs-sun);border-radius:10px;box-shadow:0 3px 0 var(--cs-sun-deep);color:#1b2340;display:flex;flex-direction:column;gap:.2rem;padding:1.4rem 1.2rem;text-decoration:none}.cs-random-button:hover{background:var(--cs-sun-deep);color:#1b2340}.cs-random-level{font-family:var(--cs-display);font-size:2.2rem;font-weight:800}.cs-random-name{font-size:1.5rem;font-weight:700}.cs-random-range{font-size:1.3rem;font-variant-numeric:tabular-nums}.cs-puzzle-meta{display:flex;flex-wrap:wrap;gap:.8rem;margin:-.4rem 0 1.2rem}.cs-rating,.cs-timer{background:var(--cs-card);border:1px solid var(--cs-line);border-radius:999px;color:var(--cs-ink);font-size:1.5rem;font-variant-numeric:tabular-nums;padding:.3rem 1rem}.cs-timer{direction:ltr;min-width:6em;text-align:center}.cs-timer-stopped{border-color:var(--cs-solved);color:var(--cs-solved);font-weight:700}.cs-catalogue>h2{font-size:3.4rem;font-weight:800;margin-bottom:1.2rem}.cs-family-nav{display:flex;flex-wrap:wrap;font-variant:normal;gap:.8rem;margin-bottom:3.2rem}.cs-family-nav a{background:var(--cs-card);border:1px solid var(--cs-line);border-radius:999px;color:var(--cs-ink);font-size:1.5rem;padding:.6rem 1.4rem;text-decoration:none}.cs-family-nav a:hover{border-color:var(--cs-ink-soft)}.cs-family{margin-bottom:4.8rem;scroll-margin-top:2rem}.cs-family>h3{font-size:2.8rem;font-weight:800;margin-bottom:.4rem}.cs-family-intro{color:var(--cs-ink-soft);font-size:1.6rem;margin-bottom:1.6rem;max-width:44em}.cs-topic-grid{display:grid;gap:1.2rem;grid-template-columns:repeat(3,minmax(0,1fr));list-style:none;margin:0;padding:0}.cs-topic{background:var(--cs-card);border:1px solid var(--cs-line);border-radius:8px;display:flex;flex-direction:column;margin:0;padding:1.6rem}.cs-topic h4{font-size:1.9rem;font-weight:700;line-height:1.25;margin:0 0 .4rem}.cs-topic h4 a{color:var(--cs-ink);text-decoration:none}.cs-topic h4 a:hover{text-decoration:underline}.cs-topic-summary{color:var(--cs-ink-soft);flex:1;font-size:1.45rem;line-height:1.4;margin-bottom:1.2rem}.cs-levels{display:grid;gap:.6rem;grid-template-columns:repeat(3,minmax(0,1fr))}.cs-level{border:1px solid var(--cs-line);border-inline-start:4px solid var(--cs-sq-dark);border-radius:6px;color:var(--cs-ink);display:flex;flex-direction:column;font-size:1.35rem;gap:.2rem;padding:.6rem .8rem;text-decoration:none}.cs-level:hover{border-color:var(--cs-ink-soft);border-inline-start-color:var(--cs-sun)}.cs-level-complete{border-inline-start-color:var(--cs-solved)}.cs-level-name{font-weight:700}.cs-level-count{color:var(--cs-ink-soft);font-variant-numeric:tabular-nums}.cs-level .cs-meter{height:.4rem}.cs-level-tabs{display:flex;flex-wrap:wrap;font-variant:normal;gap:.8rem;margin:.8rem 0 2rem}.cs-level-tab{background:var(--cs-card);border:1px solid var(--cs-line);border-radius:8px;color:var(--cs-ink);font-size:1.5rem;font-weight:700;padding:.8rem 1.4rem;text-decoration:none}.cs-level-tab span{color:var(--cs-ink-soft);font-weight:400;margin-inline-start:.6rem}.cs-level-tab-current{background:var(--cs-ink);border-color:var(--cs-ink);color:var(--cs-paper)}.cs-level-tab-current span{color:var(--cs-paper)}.cs-lesson{background:var(--cs-card);border:1px solid var(--cs-line);border-inline-start:5px solid var(--cs-sun);border-radius:8px;margin-bottom:1.6rem;max-width:46em;padding:1.6rem 2rem}.cs-lesson h2{font-size:1.8rem;font-weight:700;margin-bottom:.6rem}.cs-lesson p{font-size:1.7rem;line-height:1.55;margin:0}.cs-chapter-page h1{font-size:4.4rem;font-weight:800;margin-bottom:.8rem}.cs-crumbs{color:var(--cs-ink-soft);display:flex;font-size:1.5rem;font-variant:normal;gap:.8rem;margin-bottom:1.2rem}.cs-grid-heading{font-size:2.2rem;font-weight:700;margin:3.2rem 0 1.2rem}.cs-puzzles{display:grid;gap:.6rem;grid-template-columns:repeat(auto-fill,minmax(5.6rem,1fr));list-style:none;margin:0;padding:0}.cs-puzzles li{margin:0}.cs-puzzle{align-items:center;aspect-ratio:1;background:var(--cs-card);border:2px solid var(--cs-line);border-radius:6px;color:var(--cs-ink);display:flex;font-size:1.5rem;font-variant-numeric:tabular-nums;font-weight:700;justify-content:center;text-decoration:none}.cs-puzzle:hover{border-color:var(--cs-ink)}.cs-puzzle-solved{background:var(--cs-solved);border-color:var(--cs-solved);color:#fff}.cs-puzzle-tried{border-color:var(--cs-tried);box-shadow:inset 0 0 0 2px var(--cs-tried)}.cs-chapter-page .cs-progress-note{margin-top:2rem}.cs-legend{color:var(--cs-ink-soft);display:flex;flex-wrap:wrap;font-size:1.4rem;gap:.8rem 2.4rem;list-style:none;margin:2rem 0 0;padding:0}.cs-legend li{align-items:center;display:flex;gap:.8rem;margin:0}.cs-legend .cs-puzzle{aspect-ratio:auto;height:2rem;width:2rem}.cs-footer{border-top:1px solid var(--cs-line);box-sizing:border-box;color:var(--cs-ink-soft);font-size:1.4rem;margin:6.4rem auto 0;max-width:87rem;padding:2.4rem 0 3.2rem;width:calc(100% - 3rem)}#chessground,.cg-wrap,.cs-board{direction:ltr}[dir=rtl] .cs-board{transform:rotate(2deg)}[dir=rtl] body{text-align:right}.cs-auth{max-width:42rem}.cs-auth h1{font-size:4rem;font-weight:800;margin-bottom:1.2rem}.cs-auth h2{font-size:2.2rem;margin-top:4rem}.cs-auth-intro{color:var(--cs-ink-soft);font-size:1.7rem}.cs-auth label{font-weight:700;margin-top:1.6rem}.cs-auth input[type=email],.cs-auth input[type=password],.cs-auth input[type=text]{background:var(--cs-card);border:1px solid var(--cs-line);border-radius:8px;color:var(--cs-ink);font-size:1.7rem;height:4.6rem;margin-bottom:.4rem;width:100%}.cs-auth .cs-button{border:none;cursor:pointer;height:auto;margin-top:2.4rem}.cs-check{align-items:center;display:flex;font-weight:400!important;gap:.8rem}.cs-check input{margin:0}.cs-hint{color:var(--cs-ink-soft);display:block;font-size:1.4rem}.cs-auth .invalid-feedback,.cs-form-error{color:#b3261e;display:block;font-weight:700}[data-theme=dark] .cs-auth .invalid-feedback,[data-theme=dark] .cs-form-error{color:#ff8a80}.cs-auth-switch{font-size:1.6rem;margin-top:2.4rem}.cs-auth-switch a,.cs-danger{color:var(--cs-link);font-weight:700}.cs-danger{color:#b3261e}.cs-puzzle-chapter{color:var(--cs-ink-soft)}.cs-puzzle-chapter a{color:var(--cs-link);font-weight:700}[dir=rtl] .sidebar{margin-left:0;margin-right:2em}button.continue_button{background:var(--cs-sun);border:none;border-radius:10px;box-shadow:0 3px 0 var(--cs-sun-deep);color:#1b2340;font-family:var(--cs-display);font-size:1.8rem;font-weight:700;height:auto;padding:1.2rem 2rem}button.continue_button:focus,button.continue_button:hover{background:var(--cs-sun-deep);color:#1b2340}.cs-puzzle-note{color:var(--cs-ink-soft)}#chessground coords.files{left:0}#chessground coords.files coord{padding-right:4px;text-align:right}@media (max-width:900px){.cs-hero{gap:3rem;grid-template-columns:minmax(0,1fr) minmax(0,28rem)}.cs-hero h1{font-size:4.4rem}.cs-stage-grid{gap:4rem;grid-template-columns:minmax(0,1fr)}.cs-stage-text{min-height:0}.cs-chapter-list{display:grid;gap:0 1.2rem}.cs-chapter-list,.cs-topic-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.cs-random{grid-template-columns:minmax(0,1fr)}}@media (max-width:600px){main.container{padding:0 1.6rem}[dir=rtl] .sidebar{margin-right:0}.cs-header{margin-bottom:2.4rem}.cs-nav{gap:.8rem;padding:.8rem 1rem}.cs-brand{font-size:1.7rem;gap:.5rem}.cs-menu-icon{display:inline;font-size:1.8rem;line-height:1}.cs-menu>summary:after{display:none}.cs-menu-label{height:1px;overflow:hidden;position:absolute;width:1px;clip:rect(0 0 0 0);white-space:nowrap}.cs-brand-mark{height:2.4rem;width:2.4rem}.cs-nav-links{flex-shrink:0;gap:.2rem}.cs-menu>summary,.cs-nav-links>a{font-size:1.4rem}.cs-nav-hide-small{display:none}.cs-menu>summary,.cs-nav-links>a{padding:.8rem}.cs-hero{gap:2.4rem;grid-template-columns:minmax(0,1fr);margin-bottom:4rem}.cs-hero h1{font-size:3.6rem}.cs-lead{font-size:1.7rem}.cs-hero-board{margin:0 auto;max-width:34rem;width:100%}.cs-board{transform:none}.cs-button{text-align:center;width:100%}.cs-chapter-list{display:block}.cs-topic-grid{grid-template-columns:minmax(0,1fr)}.cs-random{padding:1.6rem}.cs-random-button{padding:1rem .8rem}.cs-random-level{font-size:1.8rem}.cs-family>h3{font-size:2.4rem}.cs-chapter{padding:1.4rem}.cs-chapter-page h1{font-size:3.4rem}}@media (prefers-reduced-motion:reduce){.cs-board,.cs-board:hover,[dir=rtl] .cs-board{transform:none;transition:none}}.cs-level-progress{margin:1.6rem 0 .4rem;max-width:48rem}.cs-level-progress .cs-meter{border-radius:999px;display:block;height:1rem}.cs-level-progress .cs-progress-note{font-size:1.5rem;font-variant-numeric:tabular-nums;font-weight:700;margin:.8rem 0 0}.cs-button-sub{display:block;font-size:1.3rem;font-weight:400;opacity:.85}.cs-hero-actions .cs-button:has(.cs-button-sub){flex-direction:column;line-height:1.3}.cs-puzzles{grid-template-columns:repeat(10,minmax(0,1fr));max-width:64rem}@media (max-width:600px){.cs-puzzles{grid-template-columns:repeat(5,minmax(0,1fr))}}.cs-puzzle-place{color:var(--cs-ink-soft);font-size:1.7rem;font-variant-numeric:tabular-nums;font-weight:700;margin:-.6rem 0 1rem}.cs-drill-line{font-size:1.6rem;font-weight:700;margin:.8rem 0;min-height:2.4rem;text-align:start;unicode-bidi:isolate}.cs-hint-button{background:var(--cs-card);border:2px solid var(--cs-ink);border-radius:999px;color:var(--cs-ink);cursor:pointer;font:inherit;font-size:1.5rem;font-weight:700;padding:.6rem 1.8rem}.cs-hint-button:focus-visible,.cs-hint-button:hover{background:var(--cs-sun,#f4c430)}.cs-opening-lesson{background:var(--cs-card);border:2px solid var(--cs-line);border-radius:12px;margin:2.4rem 0;padding:2rem}.cs-opening-lesson h2{font-size:2.2rem;margin:0 0 1.4rem}.cs-opening-lesson-body{align-items:start;display:grid;gap:2.4rem;grid-template-columns:minmax(0,36rem) minmax(0,1fr)}.cs-lesson-board-wrap{aspect-ratio:1;direction:ltr;width:100%}.cs-lesson-board{height:100%;width:100%}.cs-lesson-note{font-size:1.8rem;line-height:1.5;margin:0 0 1.4rem;min-height:6.4rem}.cs-lesson-note b{unicode-bidi:isolate}.cs-lesson-controls{align-items:center;display:flex;flex-wrap:wrap;gap:.8rem}.cs-lesson-controls button:disabled{cursor:default;opacity:.4}.cs-lesson-moves{display:flex;flex-wrap:wrap;gap:.4rem;list-style:none;margin:1.6rem 0 0;padding:0}.cs-lesson-moves li{margin:0}.cs-lesson-moves button{background:var(--cs-paper);border:1px solid var(--cs-line);border-radius:6px;color:var(--cs-ink);cursor:pointer;font:inherit;font-size:1.4rem;font-variant-numeric:tabular-nums;padding:.2rem .8rem}.cs-lesson-moves button.cs-lesson-played{background:var(--cs-sq-light)}.cs-lesson-moves button.cs-lesson-current{background:var(--cs-sun);border-color:var(--cs-sun-deep);font-weight:700}@media (max-width:760px){.cs-opening-lesson{padding:1.4rem}.cs-opening-lesson-body{grid-template-columns:minmax(0,1fr)}}.cs-hint-button,.cs-opening-lesson button{letter-spacing:normal;text-transform:none}.cs-lesson-note b{margin:0 .5rem}.cs-drill-goal{font-weight:700;margin:0 0 .6rem}.cs-drill-count{color:var(--cs-ink-soft);font-variant-numeric:tabular-nums;margin:0 0 1rem}#again{display:inline-block;margin:.8rem 0;text-decoration:none}#again.hidden{display:none}.cs-lines{display:grid;gap:.6rem;list-style:none;margin:0;max-width:64rem;padding:0}.cs-lines li{margin:0}.cs-line{align-items:center;background:var(--cs-card);border:2px solid var(--cs-line);border-radius:8px;color:var(--cs-ink);display:grid;gap:1.2rem;grid-template-columns:3.2rem minmax(0,1fr) auto;padding:1rem 1.4rem;text-decoration:none}.cs-line:hover{border-color:var(--cs-ink)}.cs-line-number{color:var(--cs-ink-soft);font-variant-numeric:tabular-nums;font-weight:700}.cs-line-name{font-weight:700}.cs-line-state{color:var(--cs-ink-soft);font-size:1.3rem}.cs-line-solved{border-color:var(--cs-solved)}.cs-line-solved .cs-line-state{color:var(--cs-solved);font-weight:700}.cs-line-tried{border-color:var(--cs-tried)}.cs-solution{margin:1rem 0}.cs-solution.hidden{display:none}.cs-solution-controls{align-items:center;display:flex;flex-wrap:wrap;gap:.8rem}.cs-solution-controls[hidden]{display:none}.cs-solution-controls button:disabled{cursor:default;opacity:.4}.cs-solution-step{color:var(--cs-ink-soft);font-variant-numeric:tabular-nums}#puzzle_hint{margin:0 0 1rem}#puzzle_hint.hidden{display:none}.cs-try{margin:3.2rem 0}.cs-try h2{font-size:2.6rem;margin:0 0 .6rem}.cs-try>p{color:var(--cs-ink-soft);margin:0 0 1.6rem}.cs-try-grid{display:grid;gap:1rem;grid-template-columns:repeat(auto-fill,minmax(18rem,1fr));list-style:none;margin:0;padding:0}.cs-try-grid li{display:flex;margin:0}.cs-try-card{background:var(--cs-card);border:2px solid var(--cs-line);border-inline-start:8px solid var(--cs-sun);border-radius:10px;color:var(--cs-ink);display:flex;flex:1;flex-direction:column;gap:.4rem;padding:1.4rem 1.6rem;text-decoration:none}.cs-try-card:focus-visible,.cs-try-card:hover{border-color:var(--cs-ink)}.cs-try-name{font-size:1.8rem;font-weight:700}.cs-try-left{color:var(--cs-ink-soft);font-size:1.4rem}.cs-try-done{border-inline-start-color:var(--cs-line)}.cs-guest-note{background:var(--cs-paper);border:1px solid var(--cs-line);border-radius:8px;margin-top:1.6rem;padding:1.2rem 1.4rem}.cs-footer-links{display:flex;flex-wrap:wrap;gap:.8rem 2.4rem}.cs-footer-links a{font-size:1.6rem;font-weight:400;text-decoration:none}.cs-footer-links a:focus-visible,.cs-footer-links a:hover{text-decoration:underline}.cs-text-page{max-width:72rem}.cs-text-page h1{margin-bottom:1.2rem}.cs-text-page h2{font-size:2.2rem;margin:3.2rem 0 1.2rem}.cs-text-page ul{padding-inline-start:2rem}.cs-text-page li{line-height:1.6;margin-bottom:.8rem}.cs-stats{display:grid;gap:1rem;grid-template-columns:repeat(auto-fill,minmax(14rem,1fr));list-style:none;margin:2.4rem 0 0;padding:0!important}.cs-stats li{background:var(--cs-card);border:2px solid var(--cs-line);border-radius:10px;color:var(--cs-ink-soft);display:flex;flex-direction:column;gap:.2rem;margin:0;padding:1.4rem 1.6rem}.cs-stat-num{color:var(--cs-ink);font-size:3rem;font-variant-numeric:tabular-nums;font-weight:700}.cs-account-family{background:var(--cs-card);border:2px solid var(--cs-line);border-radius:10px;margin-bottom:1rem}.cs-account-family summary{align-items:center;cursor:pointer;display:grid;gap:.6rem 1.6rem;grid-template-columns:minmax(0,1fr) auto;padding:1.2rem 1.6rem}.cs-account-name{font-size:1.8rem;font-weight:700}.cs-account-count{color:var(--cs-ink-soft);font-variant-numeric:tabular-nums}.cs-account-table{border-collapse:collapse;margin:0;width:100%}.cs-account-table td,.cs-account-table th{border-top:1px solid var(--cs-line);font-variant-numeric:tabular-nums;padding:.8rem 1.6rem;text-align:start}.cs-account-table th{color:var(--cs-ink-soft);font-weight:400}.cs-account-table .cs-link{font-size:inherit;font-weight:400}.cs-account-table .cs-account-done{color:var(--cs-solved);font-weight:700}ul.breadcrumb{list-style:none}ul.breadcrumb li{display:inline}ul.breadcrumb li+li:before{content:"/\00a0";padding:8px}ul.breadcrumb li a{text-decoration:none}ul.breadcrumb li a:hover{text-decoration:underline}.modal{background-color:#000;background-color:rgba(0,0,0,.4);display:none;height:100%;left:0;position:fixed;top:0;width:100%;z-index:1}.modal-content{border:1px solid var(--font-color);border-radius:var(--small-border-radius);box-shadow:var(--xl-shadow);margin:10% auto;padding:20px;width:75%}.modal-content,.modal_close{background-color:var(--bg-highlight-color)}.modal_close{float:right;font-size:28px;font-weight:700}.modal_close:focus,.modal_close:hover{color:var(--font-highlight-color);cursor:pointer;text-decoration:none}.modal_open{cursor:pointer}.popup{background:var(--bg-highlight-color);border:1px solid var(--font-color);border-radius:var(--small-border-radius);bottom:0;box-shadow:var(--m-shadow);display:inline-block;margin:20px;max-width:70vw;padding:20px;position:fixed;right:0;vertical-align:top;width:30em}.popup>span{background-color:var(--bg-highlight-color);float:right;font-size:28px;font-weight:700;margin-left:10px}.popup>span:hover{color:var(--font-highlight-color);cursor:pointer;text-decoration:none}.TextOverlay{border:1px solid #000;border-radius:50%;font-size:.8em;max-width:25ch;padding:13px;position:absolute;text-align:center;-webkit-transform:translate(-50%,-110%);-moz-transform:translate(-50%,-110%);-ms-transform:translate(-50%,-110%);-o-transform:translate(-50%,-110%);transform:translate(-50%,-110%);-webkit-user-select:none;-ms-user-select:none;user-select:none;width:max-content;z-index:10}.TextOverlayInfo{background:hsla(0,0%,100%,.85);color:#4e3030}#cookieConsent{background-color:var(--bg-color);border-top:1px solid var(--font-color);bottom:0;left:0;margin-left:auto;margin-right:auto;position:fixed;right:0;text-align:center}body{margin:0}.alert{border:1px solid transparent;border-radius:4px;margin-bottom:20px;padding:15px}.alert-info{background-color:#d9edf7;border-color:#bce8f1;color:#31708f}.alert-warning{background-color:#fcf8e3;border-color:#faebcc;color:#8a6d3b}.alert-danger{background-color:#f2dede;border-color:#ebccd1;color:#a94442}.alert p{margin-bottom:0}.alert:empty{display:none}.success{background-color:var(--success-bg);color:var(--success-color)}.info{background-color:var(--info-bg);color:var(--info-color)}.error{background-color:var(--error-bg);color:var(--error-color)}.infoBox{margin:10px 0;padding:12px;position:relative}.close_button{cursor:pointer;display:inline-block;position:absolute;right:1px;top:-5px;-webkit-user-select:none;-ms-user-select:none;user-select:none}.hidden{display:none}.box_shadow_hover:hover{box-shadow:2px 8px 8px 2px var(--drop-shadow-color)}#comments{white-space:pre-line}.big_search{margin-left:auto;margin-right:auto;width:80%}.big_input{width:100%}.deep_input{height:30em}textarea:invalid{border:2px solid red}input:invalid{border:2px solid red}blockquote:before{color:var(--font-color);content:"&";display:block;font-family:listudy;font-size:32px;left:0;position:absolute;top:-15px;transform:scaleX(-1)}blockquote{font-size:1.1em;margin:0 0 27px;padding-left:48px;position:relative}body{background-color:var(--bg-color);color:var(--font-color);font-family:Verdana,Geneva,sans-serif}.hover_warn:hover{background-color:var(--warn-color)!important}.with_sidebar{display:flex}@media only screen and (max-width:600px){.with_sidebar{display:block}.sidebar{margin-left:0!important}}.sidebar_main{flex:2;z-index:0}.sidebar{flex:1;margin-left:2em;position:relative}.continue_button{background-color:var(--primary-color);color:var(--primary-font-offset);font-size:16px;height:auto;padding:.5em 30px;width:100%}.features-header{margin:4em;text-align:center}.highlight-button{background-color:var(--primary-color);border-color:var(--primary-color);color:var(--primary-font-offset)}.opening_svg,img{max-width:100%}.opening_svg{float:right;padding-bottom:1em;padding-left:1em}.highlight{background:var(--bg-highlight-color);border-radius:var(--small-border-radius);margin-bottom:1em;padding:1em}iframe{max-width:100%}.float_right{float:right}.chessground_piece{background-size:45px;display:block;height:45px;width:45px}.settings_piece_container{display:flex}