body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}code{font-family:source-code-pro,Menlo,Monaco,Consolas,Courier New,monospace}:root{--bg-page: #f4f7f6;--bg-surface: #ffffff;--bg-subtle: #f8fafc;--text-primary: #0f172a;--text-secondary: #475569;--text-muted: #94a3b8;--border: #e2e8f0;--shadow-sm: rgba(0, 0, 0, .08);--shadow-md: rgba(0, 0, 0, .12);--overlay: rgba(0, 0, 0, .5)}:root[data-theme=dark]{--bg-page: #0f1720;--bg-surface: #182230;--bg-subtle: #212d3d;--text-primary: #e6edf3;--text-secondary: #a3b1c2;--text-muted: #7d8ea1;--border: #2d3b4c;--shadow-sm: rgba(0, 0, 0, .45);--shadow-md: rgba(0, 0, 0, .6);--overlay: rgba(0, 0, 0, .7)}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background-color:var(--bg-page);color:var(--text-primary)}.App{display:flex;flex-direction:column;min-height:100vh}header{background-color:var(--bg-surface);padding:10px 40px;box-shadow:0 2px 4px var(--shadow-sm);text-align:center;margin-bottom:20px}header h1{margin:0;color:var(--text-primary)}.main-container{display:flex;flex-wrap:wrap;justify-content:center;gap:30px;padding:0 20px;flex-grow:1}.column-card{background-color:var(--bg-surface);padding:20px;border-radius:8px;box-shadow:0 1px 3px var(--shadow-md),0 1px 2px #0000003d;display:flex;flex-direction:column;align-items:center;flex:1;min-width:400px;max-width:500px}.left-column h2,.right-column h2{text-align:center;margin-top:0;margin-bottom:20px;color:var(--text-secondary)}.image-display-area{width:100%;min-height:350px;display:flex;justify-content:center;align-items:center;margin-bottom:20px;background-color:var(--border);border-radius:4px}.image-display-area img{max-width:100%;max-height:350px;display:block}.placeholder-text{color:#888;font-style:italic}.controls{display:flex;justify-content:center;gap:15px;margin-bottom:15px;width:100%}.btn,.button{padding:8px 18px;border:none;border-radius:5px;color:#fff;font-size:.95rem;font-weight:600;cursor:pointer;transition:all .2s 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var(--shadow-sm)!important;background:#fee2e2!important}.calc-inactive{opacity:.6;border-color:var(--border)!important;color:var(--text-muted)!important;background:var(--bg-subtle)!important}.calc-inactive:hover{opacity:.85}.movetime-select{appearance:none;-webkit-appearance:none;-moz-appearance:none;background:var(--bg-surface);border:1px solid var(--border);border-radius:8px;padding:6px 24px 6px 8px;font-size:13px;font-weight:600;color:var(--text-secondary);cursor:pointer;height:38px;min-width:52px;box-shadow:0 2px 4px var(--shadow-sm);transition:all .2s cubic-bezier(.4,0,.2,1);background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='10' viewBox='0 0 12 12'%3E%3Cpath d='M3 5l3 3 3-3' fill='none' stroke='%23475569' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 8px 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5px!important}.board-controls-container{gap:8px;max-width:100%!important}.board-controls-subrow,.board-controls-group{gap:4px}.board-direction-btn{width:34px!important;height:34px!important;padding:4px!important}.movetime-select{height:34px!important;min-width:46px!important;padding:4px 18px 4px 6px!important;font-size:11px!important}.navigation-buttons{padding:6px!important;gap:4px!important}.nav-btn{padding:6px 10px!important;font-size:.95rem!important;min-width:32px!important;height:32px!important}.nav-move-counter{min-width:60px!important;font-size:.8rem!important;padding:0 4px!important}}.notation-toggle{display:flex;align-items:center;justify-content:center;gap:8px;margin-bottom:15px;font-size:.9rem;cursor:pointer;-webkit-user-select:none;user-select:none}.notation-toggle input{cursor:pointer;width:16px;height:16px;margin:0}.notation-toggle input:disabled,.notation-toggle input:disabled+span{cursor:not-allowed;opacity:.6}:root[data-theme=dark] .section{background-color:var(--bg-surface)}:root[data-theme=dark] .invalid-moves-info{background-color:#3a2417;border-color:#6b4423;color:#f0c07a}:root[data-theme=dark] .cancel-add-button{background-color:#3a1d20;border-color:#7a3a40;color:#f5a3aa}:root[data-theme=dark] .cancel-add-button:hover{background-color:#4a262a}:root[data-theme=dark] .calc-active-white{background-color:#16351f;border-color:#2f6b3f}:root[data-theme=dark] .calc-active-black{background-color:#3a1d20;border-color:#7a3a40}:root[data-theme=dark] .calc-active-black:hover{background-color:#4a262a}.theme-toggle{width:40px;height:28px;padding:2px;border:1px solid var(--border);border-radius:4px;background-color:transparent;color:var(--text-primary);cursor:pointer;display:flex;justify-content:center;align-items:center;font-size:1rem;line-height:1}.theme-toggle:hover{background-color:var(--bg-subtle)}.extra-board{width:100%;margin-top:20px;padding-top:16px;border-top:2px dashed var(--border);display:flex;flex-direction:column;align-items:center}.extra-board-title{margin:0 0 10px;color:var(--text-secondary);font-size:1rem}.extra-board-moves{margin:8px 0 0;font-size:.9rem;color:var(--text-primary)}