:root {
            --primary-color: #2c7da0;
            --secondary-color: #a9d6e5;
            --accent-color: #01497c;
            --light-gray: #f8f9fa;
            --border-color: #eaeaea;
            --text-color: #333;
            --text-muted: #6c757d;
            --success-color: #28a745;
            --warning-color: #ffc107;
            --danger-color: #dc3545;
            --island-color: #4682b4;
            --bridge-color: #8b4513;
            --double-bridge-color: #654321;
            --grid-line-color: #d3d3d3;
            --completed-island: #28a745;
            --over-connected-island: #dc3545;
        }
         
        .page-header {
            background: linear-gradient(135deg, rgba(169, 214, 229, 0.4) 0%, rgba(44, 125, 160, 0.4) 100%);
            padding: 1.5rem 0;
            margin-bottom: 2rem;
            border-bottom: 1px solid rgba(44, 125, 160, 0.2);
            position: relative;
            overflow: hidden;     color: var(--text-color);
        }
        
        .breadcrumb {
            background-color: transparent;
            padding: 0.5rem 0;
            margin-bottom: 0.5rem;
        }
        
        .breadcrumb-item a {
            color: var(--text-muted);
            text-decoration: none;
        }
        
        .breadcrumb-item.active {
            color: var(--text-color);
        }
         
        .game-area {
            display: flex;
            flex-direction: column;
            align-items: center;
            margin: 2rem 0;
        }
        
        .hashi-game-container {
            width: 100%;
            max-width: 800px;
            height: 600px;
            background-color: #f5f5f5;
            border-radius: 10px;
            position: relative;
            overflow: hidden;
            margin-bottom: 2rem;
            border: 1px solid var(--border-color);
        }
        
        .hashi-grid {
            width: 100%;
            height: 100%;
            display: grid;
            position: relative;
            background-color: white;
        }
        
        .grid-cell {
            border-right: 1px solid var(--grid-line-color);
            border-bottom: 1px solid var(--grid-line-color);
            display: flex;
            align-items: center;
            justify-content: center;
            position: relative;
        }
        
        .island {
            width: 40px;
            height: 40px;
            border-radius: 50%;
            background-color: var(--island-color);
            color: white;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: bold;
            font-size: 1.2rem;
            z-index: 2;
            box-shadow: 0 2px 5px rgba(0,0,0,0.2);
            border: 2px solid white;
            cursor: pointer;
            user-select: none;
            transition: all 0.3s ease;
            position: relative;
        }
        
        .island:hover {
            transform: scale(1.1);
            box-shadow: 0 4px 8px rgba(0,0,0,0.2);
        }
        
        .island.selected {
            box-shadow: 0 0 0 3px var(--warning-color), 0 4px 8px rgba(0,0,0,0.2);
        }
        
        .island.completed {
            background-color: var(--completed-island);
        }
        
        .island.over-connected {
            background-color: var(--over-connected-island);
        }
        
        .island .bridge-count {
            position: absolute;
            bottom: -20px;
            right: -5px;
            background-color: rgba(0,0,0,0.7);
            color: white;
            border-radius: 50%;
            width: 20px;
            height: 20px;
            font-size: 0.7rem;
            display: flex;
            align-items: center;
            justify-content: center;
        }
        
        .bridge {
            position: absolute;
            background-color: var(--bridge-color);
            z-index: 1;
            transition: all 0.3s ease;
        }
        
        .bridge:hover {
            opacity: 0.8;
        }
        
        .bridge.horizontal {
            height: 8px;
            transform: translateY(-4px);
        }
        
        .bridge.vertical {
            width: 8px;
            transform: translateX(-4px);
        }
        
        .bridge.double {
            background-color: var(--double-bridge-color);
        }
        
        .bridge.horizontal.double {
            height: 16px;
            transform: translateY(-8px);
        }
        
        .bridge.vertical.double {
            width: 16px;
            transform: translateX(-8px);
        }
        
        .bridge.preview {
            opacity: 0.6;
            background-color: #aaa;
            pointer-events: none;
        }
        
        .bridge.error {
            background-color: var(--danger-color);
        }
        
        .game-controls {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 1rem;
            margin: 1.5rem 0;
        }
        
        .game-btn {
            padding: 0.75rem 1.5rem;
            border-radius: 6px;
            font-weight: 600;
            transition: all 0.3s;
            border: none;
            display: flex;
            align-items: center;
            justify-content: center;
            min-width: 120px;
        }
        
        .game-btn-primary {
            background-color: var(--primary-color);
            color: white;
        }
        
        .game-btn-primary:hover {
            background-color: var(--accent-color);
            transform: translateY(-2px);
            box-shadow: 0 4px 8px rgba(0,0,0,0.1);
        }
        
        .game-btn-secondary {
            background-color: #6c757d;
            color: white;
        }
        
        .game-btn-secondary:hover {
            background-color: #5a6268;
            transform: translateY(-2px);
            box-shadow: 0 4px 8px rgba(0,0,0,0.1);
        }
        
        .game-btn-success {
            background-color: var(--success-color);
            color: white;
        }
        
        .game-btn-success:hover {
            background-color: #218838;
            transform: translateY(-2px);
            box-shadow: 0 4px 8px rgba(0,0,0,0.1);
        }
        
        .game-btn-warning {
            background-color: var(--warning-color);
            color: black;
        }
        
        .game-btn-warning:hover {
            background-color: #e0a800;
            transform: translateY(-2px);
            box-shadow: 0 4px 8px rgba(0,0,0,0.1);
        }
        
        .game-stats {
            display: flex;
            justify-content: space-around;
            background-color: var(--light-gray);
            border-radius: 8px;
            padding: 1.5rem;
            margin: 1.5rem 0;
            border: 1px solid var(--border-color);
        }
        
        .stat-item {
            text-align: center;
        }
        
        .stat-value {
            font-size: 2rem;
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 0.25rem;
        }
        
        .stat-label {
            color: var(--text-muted);
            font-size: 0.9rem;
        }
        
        .game-info-box {
            background-color: rgba(44, 125, 160, 0.05);
            border-left: 3px solid var(--primary-color);
            padding: 1rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        
        .game-tip-box {
            background-color: rgba(255, 193, 7, 0.05);
            border-left: 3px solid var(--warning-color);
            padding: 1rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        
        .level-selection {
            display: flex;
            flex-wrap: wrap;
            gap: 0.75rem;
            margin: 1.5rem 0;
        }
        
        .level-btn {
            padding: 0.75rem 1.5rem;
            border-radius: 6px;
            font-weight: 600;
            background-color: white;
            border: 2px solid var(--border-color);
            transition: all 0.3s;
        }
        
        .level-btn:hover {
            background-color: var(--light-gray);
        }
        
        .level-btn.active {
            background-color: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }
        
        .victory-message {
            background: linear-gradient(135deg, rgba(40, 167, 69, 0.1) 0%, rgba(40, 167, 69, 0.3) 100%);
            border: 2px solid var(--success-color);
            border-radius: 8px;
            padding: 2rem;
            text-align: center;
            margin: 2rem 0;
            display: none;
        }
        
        .victory-title {
            font-size: 2rem;
            font-weight: 700;
            color: var(--success-color);
            margin-bottom: 1rem;
        }
         
        .bridge-type-selection {
            display: flex;
            background-color: var(--light-gray);
            border-radius: 6px;
            padding: 4px;
            margin-bottom: 1.5rem;
        }
        
        .bridge-type-btn {
            flex: 1;
            text-align: center;
            padding: 0.75rem;
            border-radius: 4px;
            cursor: pointer;
            transition: all 0.3s;
            font-weight: 600;
            background-color: white;
            border: 1px solid var(--border-color);
            margin: 0 4px;
        }
        
        .bridge-type-btn.active {
            background-color: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }
        
        .tool-settings {
            display: flex;
            flex-wrap: wrap;
            gap: 1rem;
            margin: 1.5rem 0;
        }
        
        .setting-group {
            flex: 1;
            min-width: 200px;
        }
        
        .setting-label {
            font-weight: 600;
            margin-bottom: 0.5rem;
            display: block;
        }
        
        .move-history {
            background-color: var(--light-gray);
            border-radius: 8px;
            padding: 1.5rem;
            margin: 1.5rem 0;
            max-height: 300px;
            overflow-y: auto;
            border: 1px solid var(--border-color);
        }
        
        .move-history-title {
            font-weight: 600;
            margin-bottom: 1rem;
            color: var(--primary-color);
        }
        
        .move-list {
            display: flex;
            flex-direction: column;
            gap: 0.5rem;
        }
        
        .move-item {
            padding: 0.5rem;
            background-color: white;
            border-radius: 4px;
            border-left: 3px solid var(--primary-color);
            font-family: monospace;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        
        .hashi-rules {
            margin: 1.5rem 0;
        }
        
        .rule-item {
            display: flex;
            align-items: flex-start;
            margin-bottom: 1rem;
        }
        
        .rule-number {
            width: 24px;
            height: 24px;
            background-color: var(--primary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 1rem;
            flex-shrink: 0;
            font-weight: 600;
            font-size: 0.9rem;
        }
        
        .table {
            width: 100%;
            margin-bottom: 1rem;
            color: var(--text-color);
        }
        
        .table th {
            background-color: var(--light-gray);
            font-weight: 600;
        }
        
        .table-striped tbody tr:nth-of-type(odd) {
            background-color: rgba(0, 0, 0, 0.02);
        }
        
        .table-bordered {
            border: 1px solid var(--border-color);
        }
        
        .table-bordered th,
        .table-bordered td {
            border: 1px solid var(--border-color);
        }
         
        @media (max-width: 768px) { 
            .hashi-game-container {
                height: 500px;
            }
            
            .game-controls {
                flex-direction: column;
                align-items: center;
            }
            
            .game-btn {
                width: 100%;
                max-width: 300px;
            }
            
            .game-stats {
                flex-direction: column;
                gap: 1rem;
            }
            
            .island {
                width: 30px;
                height: 30px;
                font-size: 1rem;
            }
        }
        
        @media (max-width: 480px) {
            .hashi-game-container {
                height: 400px;
            }
            
            .island {
                width: 26px;
                height: 26px;
                font-size: 0.9rem;
            }
        }
    
        .difficulty-indicator {
            display: inline-block;
            padding: 0.25rem 0.75rem;
            border-radius: 20px;
            font-size: 0.85rem;
            font-weight: 500;
            margin-right: 0.5rem;
        }
        
        .difficulty-easy {
            background-color: rgba(40, 167, 69, 0.1);
            color: #28a745;
        }
        
        .difficulty-medium {
            background-color: rgba(255, 193, 7, 0.1);
            color: #ffc107;
        }
        
        .difficulty-hard {
            background-color: rgba(220, 53, 69, 0.1);
            color: #dc3545;
        }
        
        .faq-section {
            margin-top: 2rem;
        }
        
        .accordion-button:not(.collapsed) {
            background-color: rgba(44, 125, 160, 0.1);
            color: var(--primary-color);
            font-weight: 600;
        }
        
        .accordion-button:focus {
            box-shadow: 0 0 0 3px rgba(44, 125, 160, 0.25);
            border-color: var(--primary-color);
        }
        
        .btn {
            border-radius: 6px;
            padding: 0.75rem 1.5rem;
            font-weight: 600;
            transition: all 0.3s;
        }
        
        .btn-primary {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
        }
        
        .btn-primary:hover {
            background-color: var(--accent-color);
            border-color: var(--accent-color);
            transform: translateY(-1px);
            box-shadow: 0 4px 8px rgba(0,0,0,0.1);
        }
        
        .btn-outline-primary {
            color: var(--primary-color);
            border-color: var(--primary-color);
        }
        
        .btn-outline-primary:hover {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            color: white;
        }
        
        .alert {
            border-radius: 6px;
            border: 1px solid transparent;
            padding: 1rem;
            margin-bottom: 1rem;
        }
        
        .alert-success {
            background-color: rgba(40, 167, 69, 0.1);
            border-color: rgba(40, 167, 69, 0.2);
            color: #155724;
        }
        
        .alert-info {
            background-color: rgba(23, 162, 184, 0.1);
            border-color: rgba(23, 162, 184, 0.2);
            color: #0c5460;
        }
        
        .alert-warning {
            background-color: rgba(255, 193, 7, 0.1);
            border-color: rgba(255, 193, 7, 0.2);
            color: #856404;
        }
        
        .alert-danger {
            background-color: rgba(220, 53, 69, 0.1);
            border-color: rgba(220, 53, 69, 0.2);
            color: #721c24;
        }
        
        hr {
            border: 0;
            border-top: 1px solid var(--border-color);
            margin: 1.5rem 0;
        }
        
        .keyboard-shortcuts {
            background-color: var(--light-gray);
            border-radius: 8px;
            padding: 1.5rem;
            margin: 1.5rem 0;
        }
        
        .shortcut-item {
            display: flex;
            justify-content: space-between;
            padding: 0.5rem 0;
            border-bottom: 1px solid rgba(0,0,0,0.05);
        }
        
        .shortcut-key {
            background-color: white;
            border: 1px solid #ddd;
            border-radius: 4px;
            padding: 0.25rem 0.5rem;
            font-family: monospace;
            font-weight: bold;
        }
        
        .game-instructions {
            background-color: var(--light-gray);
            border-radius: 8px;
            padding: 1.5rem;
            margin: 1.5rem 0;
        }
        
        .instruction-step {
            display: flex;
            align-items: center;
            margin-bottom: 1rem;
        }
        
        .instruction-icon {
            width: 40px;
            height: 40px;
            background-color: var(--primary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 1rem;
            flex-shrink: 0;
        }
        
        .island-tooltip {
            position: absolute;
            background-color: rgba(0,0,0,0.8);
            color: white;
            padding: 0.5rem;
            border-radius: 4px;
            font-size: 0.8rem;
            z-index: 100;
            pointer-events: none;
            opacity: 0;
            transition: opacity 0.3s;
            white-space: nowrap;
        }
        
        .hint-highlight {
            animation: pulse 1s infinite;
        }
        
        @keyframes pulse {
            0% { box-shadow: 0 0 0 0 rgba(255, 193, 7, 0.7); }
            70% { box-shadow: 0 0 0 10px rgba(255, 193, 7, 0); }
            100% { box-shadow: 0 0 0 0 rgba(255, 193, 7, 0); }
        }
        
        .bridge-count-display {
            display: inline-block;
            margin-left: 0.5rem;
            padding: 0.25rem 0.5rem;
            background-color: var(--light-gray);
            border-radius: 4px;
            font-weight: bold;
        }
        
        .puzzle-complexity {
            display: flex;
            align-items: center;
            justify-content: space-between;
            margin: 1rem 0;
        }
        
        .complexity-bar {
            flex: 1;
            height: 8px;
            background-color: #e9ecef;
            border-radius: 4px;
            overflow: hidden;
            margin: 0 1rem;
        }
        
        .complexity-fill {
            height: 100%;
            background-color: var(--primary-color);
            border-radius: 4px;
            width: 0%;
            transition: width 1s ease;
        }