* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            padding: 10px;
            overflow: auto;
        }

        .game-container {
            background: rgba(255, 255, 255, 0.95);
            border-radius: 16px;
            padding: 30px;
            box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
            text-align: center;
            max-width: 500px;
            width: 100%;
        }

        h1 {
            color: #333;
            margin-bottom: 30px;
            font-size: 32px;
        }

        .length-section {
            margin-bottom: 30px;
        }

        .length-section label {
            display: block;
            font-size: 16px;
            color: #666;
            font-weight: 600;
            margin-bottom: 10px;
        }

        .length-control {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 15px;
            margin-bottom: 10px;
        }

        #lengthSlider {
            flex: 1;
            max-width: 250px;
            height: 8px;
            border-radius: 5px;
            outline: none;
            background: #e0e0e0;
        }

        #lengthSlider::-webkit-slider-runnable-track {
            height: 8px;
            border-radius: 5px;
            background: linear-gradient(to right, #667eea 0%, #764ba2 100%);
        }

        #lengthSlider::-moz-range-track {
            height: 8px;
            border-radius: 5px;
            background: linear-gradient(to right, #667eea 0%, #764ba2 100%);
        }

        #lengthSlider::-webkit-slider-thumb {
            -webkit-appearance: none;
            appearance: none;
            width: 20px;
            height: 20px;
            border-radius: 50%;
            background: #667eea;
            cursor: pointer;
            box-shadow: 0 2px 8px rgba(102, 126, 234, 0.4);
        }

        #lengthSlider::-moz-range-thumb {
            width: 20px;
            height: 20px;
            border-radius: 50%;
            background: #667eea;
            cursor: pointer;
            border: none;
            box-shadow: 0 2px 8px rgba(102, 126, 234, 0.4);
        }

        #lengthValue {
            font-size: 24px;
            font-weight: bold;
            color: #667eea;
            min-width: 40px;
        }

        .options-section {
            margin-bottom: 30px;
            text-align: left;
        }

        .options-section h3 {
            font-size: 18px;
            color: #666;
            margin-bottom: 15px;
            text-align: center;
        }

        .checkbox-group {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .checkbox-item {
            display: flex;
            align-items: center;
            gap: 10px;
            padding: 12px;
            background: #f5f5f5;
            border-radius: 8px;
            transition: background 0.3s ease;
        }

        .checkbox-item:hover {
            background: #e8e8e8;
        }

        .checkbox-item input[type="checkbox"] {
            width: 20px;
            height: 20px;
            cursor: pointer;
            accent-color: #667eea;
        }

        .checkbox-item label {
            cursor: pointer;
            font-size: 16px;
            color: #333;
            flex: 1;
        }

        .password-display {
            background: #f5f5f5;
            border: 3px solid #667eea;
            border-radius: 8px;
            padding: 20px;
            margin-bottom: 20px;
            min-height: 70px;
            display: flex;
            align-items: center;
            justify-content: center;
            word-break: break-all;
            font-family: 'Courier New', monospace;
            font-size: 18px;
            color: #333;
            font-weight: bold;
            position: relative;
        }

        .password-display.empty {
            color: #999;
            font-style: italic;
        }

        .copy-btn {
            position: absolute;
            top: 10px;
            right: 10px;
            background: #667eea;
            color: white;
            border: none;
            border-radius: 6px;
            padding: 6px 12px;
            font-size: 12px;
            cursor: pointer;
            transition: all 0.2s ease;
        }

        .copy-btn:hover {
            background: #764ba2;
            transform: scale(1.05);
        }

        .copy-btn.copied {
            background: #4ECDC4;
        }

        .buttons {
            display: flex;
            gap: 10px;
            justify-content: center;
            flex-wrap: wrap;
            margin-bottom: 20px;
        }

        .btn {
            padding: 15px 35px;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            border: none;
            border-radius: 8px;
            font-size: 18px;
            font-weight: 600;
            cursor: pointer;
            transition: transform 0.2s ease, box-shadow 0.2s ease;
            text-decoration: none;
            display: inline-block;
        }

        .btn:hover:not(:disabled) {
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
        }

        .btn:active:not(:disabled) {
            transform: translateY(0);
        }

        .btn:disabled {
            background: #ccc;
            cursor: not-allowed;
            transform: none;
        }

        .btn.secondary {
            background: #888;
        }

        .btn.secondary:hover {
            box-shadow: 0 6px 20px rgba(136, 136, 136, 0.4);
        }

        .error-message {
            color: #ff6b6b;
            font-size: 14px;
            margin-top: 10px;
            opacity: 0;
            transition: opacity 0.3s ease;
        }

        .error-message.show {
            opacity: 1;
        }

        .strength-meter {
            margin-top: 15px;
            text-align: left;
        }

        .strength-label {
            font-size: 14px;
            color: #666;
            margin-bottom: 8px;
        }

        .strength-bar-container {
            width: 100%;
            height: 10px;
            background: #e0e0e0;
            border-radius: 5px;
            overflow: hidden;
        }

        .strength-bar {
            height: 100%;
            width: 0%;
            transition: width 0.3s ease, background-color 0.3s ease;
            border-radius: 5px;
        }

        .strength-bar.weak {
            width: 33%;
            background: #ff6b6b;
        }

        .strength-bar.medium {
            width: 66%;
            background: #FFA07A;
        }

        .strength-bar.strong {
            width: 100%;
            background: #4ECDC4;
        }

        @media (max-width: 480px) {
            h1 {
                font-size: 26px;
                margin-bottom: 20px;
            }

            .game-container {
                padding: 20px;
            }

            .password-display {
                font-size: 16px;
                padding: 15px;
            }

            .btn {
                padding: 12px 25px;
                font-size: 16px;
            }

            .checkbox-item {
                padding: 10px;
            }
        }