/* --- Global Styles & Variables --- */
        :root {
            --primary-color: #007bff;
            --primary-hover-color: #0056b3;
            --secondary-color: #6c757d;
            --secondary-hover-color: #5a6268;
            --success-color: #28a745;
            --success-bg-color: #d4edda;
            --success-border-color: #c3e6cb;
            --danger-color: #dc3545;
            --danger-bg-color: #f8d7da;
            --danger-border-color: #f5c6cb;
            --warning-color: #ffc107;
            --info-color: #17a2b8;
            --light-gray: #f8f9fa;
            --medium-gray: #e9ecef;
            --dark-gray: #6c757d;
            --text-color: #333;
            --border-color: #dee2e6;
            --sidebar-width: 400px;
            --sidebar-width-mobile: 320px;
            --font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            --base-font-size: 16px;
            /* Base for rem units */
            --border-radius: 0.375rem;
            /* 6px */
            --box-shadow: 0 2px 10px rgba(0, 0, 0, 0.075);
            --transition-speed: 0.2s;
        }

        *,
        *::before,
        *::after {
            box-sizing: border-box;
        }

        html {
            font-size: var(--base-font-size);
            scroll-behavior: smooth;
        }

        body {
            font-family: var(--font-family);
            margin: 0;
            padding: 0;
            background-color: var(--light-gray);
            color: var(--text-color);
            line-height: 1.6;
            position: relative;
            padding-left: 0;
            transition: padding-left var(--transition-speed) ease-in-out;
        }

        body.sidebar-open {
            padding-left: var(--sidebar-width);
        }

        /* --- Container --- */
        .container {
            width: 95%;
            max-width: 900px;
            margin: 2rem auto;
            /* More vertical spacing */
            background-color: #fff;
            padding: 1.5rem;
            /* Increased padding */
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
            box-sizing: border-box;
            transition: margin-left var(--transition-speed) ease-in-out;
        }

        h1 {
            font-size: 1.75rem;
            font-weight: 600;
            margin-top: 0;
            margin-bottom: 1.5rem;
            color: var(--primary-color);
            text-align: center;
        }

        /* --- Sidebar Styles --- */
        .sidebar {
            position: fixed;
            top: 0;
            left: 0;
            width: var(--sidebar-width);
            height: 100vh;
            background-color: #fff;
            /* Changed background */
            border-right: 1px solid var(--border-color);
            padding: 1.5rem;
            box-sizing: border-box;
            overflow-y: auto;
            transform: translateX(-100%);
            transition: transform var(--transition-speed) ease-in-out;
            z-index: 1000;
            box-shadow: var(--box-shadow);
        }

        .sidebar.open {
            transform: translateX(0);
        }

        .sidebar h2 {
            margin-top: 0;
            margin-bottom: 1.5rem;
            font-size: 1.25rem;
            font-weight: 600;
            border-bottom: 1px solid var(--border-color);
            padding-bottom: 0.75rem;
            color: var(--primary-color);
        }

        .sidebar-section {
            margin-bottom: 1.5rem;
        }

        .sidebar-section h3 {
            margin-top: 0;
            margin-bottom: 0.75rem;
            font-size: 1rem;
            font-weight: 600;
            color: var(--dark-gray);
        }

        .sidebar-section label {
            display: block;
            margin-bottom: 0.5rem;
            /* Reduced spacing */
            font-size: 0.9rem;
            cursor: pointer;
            padding: 0.25rem 0;
            /* Add padding for easier clicking */
        }

        .sidebar-section label input[type="checkbox"],
        .sidebar-section label input[type="radio"] {
            margin-right: 0.5rem;
            vertical-align: middle;
            accent-color: var(--primary-color);
            /* Style checkbox/radio */
        }

        .filter-options-list {
            max-height: 180px;
            /* Slightly taller */
            overflow-y: auto;
            border: 1px solid var(--border-color);
            padding: 0.75rem;
            background-color: var(--light-gray);
            border-radius: var(--border-radius);
            margin-top: 0.5rem;
        }

        /* Style scrollbar for filter lists */
        .filter-options-list::-webkit-scrollbar {
            width: 8px;
        }

        .filter-options-list::-webkit-scrollbar-track {
            background: var(--light-gray);
        }

        .filter-options-list::-webkit-scrollbar-thumb {
            background: #ccc;
            border-radius: 4px;
        }

        .filter-options-list::-webkit-scrollbar-thumb:hover {
            background: #aaa;
        }


        .sidebar button,
        button {
            /* General button styling */
            display: inline-block;
            padding: 0.6rem 1.2rem;
            /* Adjusted padding */
            font-size: 0.95rem;
            /* Slightly larger */
            font-weight: 500;
            color: white;
            background-color: var(--primary-color);
            border: none;
            border-radius: var(--border-radius);
            cursor: pointer;
            margin-right: 0.5rem;
            margin-bottom: 0.5rem;
            /* Space below buttons */
            transition: background-color var(--transition-speed), box-shadow var(--transition-speed);
            text-align: center;
            vertical-align: middle;
            line-height: 1.5;
        }

        .sidebar button {
            width: 100%;
            /* Sidebar buttons take full width */
            margin-top: 1rem;
            margin-right: 0;
            /* Reset margin for full width */
        }

        button:hover:not(:disabled) {
            background-color: var(--primary-hover-color);
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
        }

        button:disabled {
            background-color: #ccc;
            cursor: not-allowed;
            opacity: 0.7;
        }

        .clear-filter-button {
            font-size: 0.8em !important;
            padding: 0.25rem 0.5rem !important;
            width: auto !important;
            margin-top: 0.5rem !important;
            background-color: var(--secondary-color) !important;
        }

        .clear-filter-button:hover:not(:disabled) {
            background-color: var(--secondary-hover-color) !important;
        }

        #show-performance-button {
            background-color: var(--info-color);
        }

        #close-sidebar-button {
            background-color: var(--secondary-color);
        }

        #close-sidebar-button:hover {
            background-color: var(--secondary-hover-color);
        }

        /* --- Sidebar Toggle Button --- */
        #sidebar-toggle-button {
            position: fixed;
            top: 10px;
            left: 10px;
            z-index: 1001;
            padding: 0.5rem 0.75rem;
            /* Adjusted padding */
            background-color: var(--primary-color);
            color: white;
            border: none;
            border-radius: var(--border-radius);
            cursor: pointer;
            font-size: 1.25rem;
            /* Larger icon */
            line-height: 1;
            transition: background-color var(--transition-speed), left var(--transition-speed) ease-in-out, transform var(--transition-speed);
            box-shadow: var(--box-shadow);
        }

        #sidebar-toggle-button:hover {
            background-color: var(--primary-hover-color);
            transform: scale(1.05);
        }

        body.sidebar-open #sidebar-toggle-button {
            left: calc(var(--sidebar-width) + 10px);
            background-color: var(--danger-color);
        }

        body.sidebar-open #sidebar-toggle-button:hover {
            background-color: #c82333;
        }

        /* --- File/Quiz Controls --- */
        .file-controls {
            margin-top: 2rem;
            /* Add space above */
            margin-bottom: 1rem;
            padding-top: 1.5rem;
            border-top: 1px solid var(--border-color);
            /* Use top border */
            display: flex;
            flex-direction: column;
            /* Stack vertically */
            gap: 0.75rem;
            /* Spacing between items */
            align-items: flex-start;
            /* Align items left */
        }

        .file-controls .control-group {
            display: flex;
            align-items: center;
            gap: 0.75rem;
            width: 100%;
        }

        .file-controls label {
            margin: 0;
            font-weight: 500;
            white-space: nowrap;
            /* Prevent label wrapping */
        }

        .file-controls input[type="file"] {
            margin: 0;
            border: 1px solid var(--border-color);
            padding: 0.4rem 0.8rem;
            border-radius: var(--border-radius);
            background-color: #fff;
            cursor: pointer;
            flex-grow: 1;
            /* Allow input to take space */
            /* Limit max width if needed */
            max-width: calc(100% - 150px);
            /* Adjust based on button size */
        }

        .file-controls button {
            width: auto;
            /* Let button size naturally */
            flex-shrink: 0;
            /* Prevent button shrinking */
        }

        .file-controls p.auto-save-info {
            font-size: 0.85rem;
            color: var(--secondary-color);
            margin: 0.5rem 0 0 0;
            width: 100%;
            /* Span full width */
            text-align: center;
            /* Center the text */
        }

        .quiz-controls {
            margin-bottom: 1.5rem;
            /* Added */
            padding-bottom: 0;
            /* Modified */
            border-bottom: none;
            /* No border for bottom controls */
            display: flex;
            /* Added */
            justify-content: flex-end;
            /* Align Next button right */
            gap: 0.75rem;
            /* Added */
        }


        #quiz-area {
            display: none;
            padding-bottom: 1rem;
            border-bottom: 1px solid var(--border-color);
            /* Initially hidden */
        }

        #quiz-progress {
            text-align: right;
            margin-bottom: 1rem;
            font-size: 0.9rem;
            color: var(--dark-gray);
        }

        /* --- Question Group Intro --- */
        .question-group-intro {
            background-color: #e9f5ff;
            /* Softer blue */
            padding: 1rem 1.25rem;
            margin-bottom: 1.5rem;
            border-left: 4px solid var(--primary-color);
            border-radius: var(--border-radius);
        }

        .question-group-intro h3 {
            margin-top: 0;
            margin-bottom: 0.5rem;
            font-size: 1.1rem;
            font-weight: 400;
        }

        .question-group-intro p {
            margin-bottom: 0;
            font-size: 0.95rem;
            color: #444;
        }

        /* --- Question Card --- */
        .question-card {
            margin-bottom: 1.5rem;
            padding: 1.5rem;
            border: 1px solid var(--border-color);
            border-radius: var(--border-radius);
            background-color: #fff;
            /* Ensure background */
            box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
        }

        /* --- Tooltip for Question Meta --- */
        .question-meta-container {
            position: relative;
            /* Context for tooltip */
            margin-top: -1.1rem;
            margin-bottom: 0.3rem;
            text-align: right;
            user-select: none;
            /* Position trigger icon */
        }

        .meta-tooltip-trigger {
            display: inline-block;
            cursor: help;
            /* Indicate interactivity */
            font-size: 0.9rem;
            /* Make it circular */
            line-height: 1;
            user-select: none;
            /* Prevent text selection */
            transition: background-color var(--transition-speed), color var(--transition-speed);
        }

        .meta-tooltip-trigger:hover,
        .meta-tooltip-trigger:focus {
            background-color: var(--secondary-color);
            color: white;
            outline: none;
            /* Remove default focus ring if needed */
        }

        .tooltip-text {
            position: absolute;
            bottom: 125%;
            /* Position above the trigger */
            right: 0;
            /* Align to the right of trigger */
            /* left: 50%; */
            /* Use this for centered */
            /* transform: translateX(-50%); */
            /* Use this for centered */
            transform: translateX(10%);
            /* Slightly offset */
            min-width: 250px;
            /* Minimum width */
            max-width: 350px;
            /* Max width */
            background-color: #333;
            /* Dark background */
            color: #fff;
            text-align: left;
            /* Align text left */
            padding: 0.75rem 1rem;
            border-radius: var(--border-radius);
            font-size: 0.85rem;
            line-height: 1.4;
            z-index: 20;
            /* Ensure it's above other content */
            visibility: hidden;
            /* Hidden by default */
            opacity: 0;
            transition: opacity var(--transition-speed) ease-in-out, visibility var(--transition-speed) ease-in-out;
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
            white-space: normal;
            /* Allow text wrapping */
            pointer-events: none;
            /* Tooltip itself isn't interactive */
        }

        /* Triangle/Arrow for Tooltip */
        .tooltip-text::after {
            content: "";
            position: absolute;
            top: 100%;
            /* At the bottom of the tooltip */
            right: 15px;
            /* Position arrow near the trigger */
            /* left: 50%; */
            /* Use this for centered */
            /* margin-left: -5px; */
            /* Use this for centered */
            border-width: 5px;
            border-style: solid;
            border-color: #333 transparent transparent transparent;
            /* Arrow pointing down */
        }

        .meta-tooltip-trigger:hover+.tooltip-text,
        .meta-tooltip-trigger:focus+.tooltip-text {
            visibility: visible;
            opacity: 1;
        }

        /* Question Text Styling */
        #question-text {
            font-size: 1.15rem;
            /* Reduced font size */
            font-weight: 400;
            /* Normal weight */
            margin-top: 0;
            margin-bottom: 1.5rem;
            /* Spacing below question */
            line-height: 1.5;
            /* Improve readability */
            color: #212529;
            /* Slightly darker than default text */
        }

        /* Choices Form */
        .choices-form .choice-item {
            margin-bottom: 0.5rem;
            /* Tighter spacing between choices */
        }

        .choices-form label {
            display: block;
            margin-bottom: 0;
            /* Remove margin handled by choice-item */
            padding: 0.8rem 1rem;
            /* More padding */
            border: 1px solid var(--border-color);
            border-radius: var(--border-radius);
            cursor: pointer;
            transition: background-color var(--transition-speed), border-color var(--transition-speed);
            line-height: 1.4;
            background-color: #fff;
            /* Ensure background */
        }

        .choices-form label:hover {
            background-color: var(--light-gray);
            border-color: #adb5bd;
        }

        .choices-form label:has(input[type="radio"]:checked) {
            background-color: #e6f2ff;
            /* Slightly softer blue */
            border-color: var(--primary-color);
        }

        .choices-form label.correct-answer {
            background-color: var(--success-bg-color);
            border-color: var(--success-color);
            color: var(--success-color);
            /* Darker text for contrast */
            font-weight: 600;
        }

        .choices-form label.selected-incorrect {
            background-color: var(--danger-bg-color);
            border-color: var(--danger-color);
            color: var(--danger-color);
            /* Darker text for contrast */
        }

        /* Ensure correct/incorrect styles override hover/checked */
        .choices-form label.correct-answer:hover,
        .choices-form label.selected-incorrect:hover {
            background-color: inherit;
            /* Keep the feedback color */
        }


        .choices-form input[type="radio"] {
            margin-right: 0.75rem;
            /* More space */
            vertical-align: middle;
            width: 1em;
            /* Control size */
            height: 1em;
            accent-color: var(--primary-color);
        }

        /* Hide actual radio button, style the label */
        /* Optional: More advanced custom radio styling can go here */

        .choices-form label span {
            vertical-align: middle;
        }

        /* Feedback Area */
        .feedback-area {
            margin-top: 1.5rem;
            padding: 1rem 1.25rem;
            border-radius: var(--border-radius);
            border: 1px solid transparent;
            font-size: 0.95rem;
        }

        .feedback-area.correct {
            background-color: var(--success-bg-color);
            color: #0f5132;
            /* Darker green text */
            border-color: var(--success-border-color);
        }

        .feedback-area.incorrect {
            background-color: var(--danger-bg-color);
            color: #842029;
            /* Darker red text */
            border-color: var(--danger-border-color);
        }

        .feedback-area p {
            margin-bottom: 0.5rem;
        }

        /* Space between result and explanation */
        .feedback-area strong {
            font-weight: 600;
        }

        .explanation {
            margin-top: 0.75rem;
            padding-top: 0.75rem;
            border-top: 1px dashed var(--border-color);
            white-space: pre-wrap;
            word-wrap: break-word;
            font-size: 0.9rem;
            color: #495057;
            /* Slightly muted color */
        }

        .explanation strong {
            font-weight: 600;
            color: var(--text-color);
            /* Make 'Explanation:' stand out */
        }

        .ai-generated-flag {
            background: grey;
            color: white;
        }


        /* User Notes */
        .user-notes {
            margin-top: 1.5rem;
        }

        .user-notes label {
            display: block;
            margin-bottom: 0.5rem;
            font-weight: 500;
            font-size: 0.9rem;
        }

        .user-notes textarea {
            width: 100%;
            max-width: 100%;
            margin-top: 0;
            padding: 0.75rem 1rem;
            border-radius: var(--border-radius);
            border: 1px solid var(--border-color);
            box-sizing: border-box;
            transition: background-color var(--transition-speed), border-color var(--transition-speed);
            font-family: inherit;
            /* Use body font */
            font-size: 0.95rem;
            line-height: 1.5;
        }

        .user-notes textarea:focus {
            border-color: var(--primary-color);
            outline: none;
            box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
        }

        .user-notes textarea:disabled {
            background-color: var(--medium-gray);
            cursor: not-allowed;
            opacity: 0.8;
        }

        /* Past Attempts */
        .past-attempts {
            margin-top: 1.5rem;
            padding-top: 1.5rem;
            border-top: 1px solid var(--border-color);
        }

        .past-attempts h4 {
            margin-top: 0;
            margin-bottom: 1rem;
            font-size: 1rem;
            font-weight: 600;
        }

        .past-attempts ul {
            list-style-type: none;
            padding-left: 0;
            margin: 0;
        }

        .past-attempts li {
            background-color: var(--light-gray);
            padding: 0.8rem 1rem;
            margin-bottom: 0.5rem;
            border-radius: var(--border-radius);
            font-size: 0.85rem;
            /* Slightly smaller */
            word-wrap: break-word;
            border: 1px solid var(--border-color);
            line-height: 1.5;
        }

        .past-attempts li strong {
            font-weight: 600;
        }

        .past-attempts li em {
            font-style: normal;
            color: #555;
        }

        /* Notes styling */

        .past-attempts .attempt-correct {
            color: var(--success-color);
        }

        .past-attempts .attempt-incorrect {
            color: var(--danger-color);
        }

        /* Accordion Styles for Past Attempts */
        .accordion-toggle {
            background-color: var(--medium-gray);
            color: var(--text-color);
            cursor: pointer;
            padding: 0.75rem 1.25rem;
            width: 100%;
            border: none;
            text-align: left;
            outline: none;
            font-size: 0.95rem;
            font-weight: 600;
            border-radius: var(--border-radius);
            transition: background-color var(--transition-speed);
            margin-bottom: 0; /* Remove margin if content is directly below */
        }

        .accordion-toggle:hover {
            background-color: #d3d9df; /* Slightly darker medium-gray */
        }

        .accordion-toggle::after {
            content: '\25BC'; /* Right-pointing triangle (Play icon) */
            font-size: 0.8rem;
            color: var(--secondary-color);
            float: right;
            margin-left: 5px;
            transition: transform var(--transition-speed);
        }

        .accordion-toggle[aria-expanded="true"]::after {
            transform: rotate(90deg); /* Down-pointing triangle */
        }

        .accordion-content {
            padding: 0; /* Remove padding if items inside have their own */
            background-color: white;
            overflow: hidden;
            transition: max-height 0.3s ease-out, padding 0.3s ease-out;
            max-height: 0; /* Hidden by default */
            border: 1px solid var(--border-color);
            border-top: none; /* Avoid double border with toggle */
            border-radius: 0 0 var(--border-radius) var(--border-radius); /* Match toggle */
        }

        .accordion-content.open {
            padding: 1rem; /* Add padding when open */
            /* max-height will be set by JS to fit content */
        }

        /* Ensure the h4 and ul inside accordion-content are styled appropriately */
        .accordion-content h4 {
            margin-top: 0; /* Reset margin if accordion-content has padding */
            margin-bottom: 0.75rem;
            font-size: 0.9rem; /* Slightly smaller than original */
            font-weight: 600;
            color: var(--dark-gray);
        }

        .accordion-content ul {
            padding-left: 0; /* Align with accordion padding */
            margin-bottom: 0; /* Reset margin */
        }
        /* Past Attempts list items remain styled as before by .past-attempts li */


        /* End of Quiz Message */
        #end-of-quiz-message {
            display: none;
            padding: 1.5rem;
            text-align: center;
            background-color: #d1ecf1;
            /* Info background */
            color: #0c5460;
            /* Darker info text */
            border: 1px solid #bee5eb;
            border-radius: var(--border-radius);
            margin-top: 2rem;
        }

        #end-of-quiz-message h2 {
            margin-top: 0;
            font-size: 1.5rem;
        }

        /* Annotation Styles */
        #annotation-area {
            position: relative;
            padding-bottom: 1px;
            margin-bottom: 1rem;
            min-height: 150px;
        }

        /* Space below canvas area */
        #annotation-spacer {
            height: 100px;
        }

        /* Keep spacer */
        #annotationCanvas {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            z-index: 10;
            cursor: crosshair;
            display: none;
            touch-action: none;
            border-radius: var(--border-radius);
            background: transparent;
        }

        #annotationCanvas.annotation-active {
            pointer-events: auto;
        }

        #annotation-controls {
            margin-top: 1rem;
            margin-bottom: 1rem;
            padding: 0.75rem;
            background-color: var(--medium-gray);
            border-radius: var(--border-radius);
            display: none;
            border: 1px solid var(--border-color);
            text-align: center;
            /* Center controls */
        }

        #annotation-controls span {
            font-weight: 600;
            margin-right: 1rem;
            display: inline-block;
            margin-bottom: 0.5rem;
            font-size: 0.9rem;
        }

        #annotation-controls button {
            background-color: var(--secondary-color);
            margin-right: 0.5rem;
            padding: 0.4rem 0.8rem;
            font-size: 0.85rem;
            margin-bottom: 0;
            /* Reset margin */
            color: white;
            opacity: 0.8;
        }

        #annotation-controls button:hover:not(:disabled) {
            background-color: var(--secondary-hover-color);
            opacity: 1;
        }

        #annotation-controls button.active-tool {
            background-color: var(--primary-color);
            border: 1px solid var(--primary-hover-color);
            color: white;
            opacity: 1;
            box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.2);
        }

        #annotation-controls button#clearAnnotationButton {
            background-color: var(--danger-color);
        }

        #annotation-controls button#clearAnnotationButton:hover {
            background-color: #c82333;
        }

        #toggleAnnotationButton {
            margin-bottom: 1rem;
            background-color: var(--info-color);
        }

        #toggleAnnotationButton:hover {
            background-color: #117a8b;
        }

        #toggleAnnotationButton.annotation-active {
            background-color: var(--warning-color);
            color: #333;
        }

        #toggleAnnotationButton.annotation-active:hover {
            background-color: #e0a800;
        }


        /* --- Responsive Design --- */

        /* Tablet and Smaller */
        @media (max-width: 992px) {
            .container {
                width: 95%;
                padding: 1.25rem;
            }

            h1 {
                font-size: 1.6rem;
            }

            #question-text {
                font-size: 1.1rem;
            }

            /* Ensure container aligns correctly with open sidebar on tablets */
            body.sidebar-open .container {
                margin-left: 0; /* Align to the new "left edge" created by body's padding-left */
                                /* The 'width: 95%' from this media query will apply. */
                                /* The 'margin-right: auto' from the default 'margin: 2rem auto' will handle the right side. */
            }
        }

        /* Mobile Devices */
        @media (max-width: 767px) {
            body.sidebar-open {
                padding-left: 0;
                /* Disable body padding shift */
            }

            .sidebar {
                width: var(--sidebar-width-mobile);
                /* Slightly narrower */
                box-shadow: 0 0 15px rgba(0, 0, 0, 0.2);
                /* More prominent shadow when open */
            }

            body.sidebar-open #sidebar-toggle-button {
                left: calc(var(--sidebar-width-mobile) + 10px);
                /* Adjust toggle button position */
            }

            .container {
                width: 100%;
                margin: 1rem 0;
                /* Edge-to-edge basically */
                padding: 1rem;
                border-radius: 0;
                /* Remove radius for full width */
                box-shadow: none;
                /* Remove shadow for full width */
                border-top: 1px solid var(--border-color);
                /* Add separation */
                border-bottom: 1px solid var(--border-color);
            }

            h1 {
                font-size: 1.4rem;
                margin-bottom: 1rem;
            }

            .file-controls {
                align-items: stretch;
                /* Stretch items like input */
            }

            .file-controls .control-group {
                flex-direction: column;
                /* Stack label/input/button */
                align-items: stretch;
                gap: 0.5rem;
            }

            .file-controls input[type="file"] {
                width: 100%;
                max-width: 100%;
                /* Override desktop max-width */
                margin-bottom: 0.5rem;
                /* Space before button */
            }

            .file-controls button {
                width: 100%;
                /* Full width buttons */
                margin-right: 0;
            }

            .file-controls p.auto-save-info {
                text-align: left;
                /* Align left on mobile */
                margin-top: 0.75rem;
            }


            #quiz-progress {
                margin-bottom: 0.75rem;
            }

            .question-card {
                padding: 1rem;
            }

            #question-text {
                font-size: 1.05rem;
            }

            /* Slightly smaller on mobile */
            .choices-form label {
                padding: 0.75rem 0.9rem;
            }

            /* Adjust padding */

            .feedback-area,
            .user-notes,
            .past-attempts {
                margin-top: 1rem;
                padding-top: 1rem;
            }

            .past-attempts li {
                padding: 0.6rem 0.8rem;
                font-size: 0.8rem;
            }

            button {
                padding: 0.7rem 1rem;
                font-size: 0.9rem;
            }

            /* Ensure buttons are tappable */
            .quiz-controls {
                margin-top: 1rem;
            }

            .tooltip-text {
                /* Adjust tooltip positioning/size for mobile if needed */
                max-width: 80vw;
                /* Limit width more strictly */
                bottom: auto;
                /* Position below trigger */
                top: 115%;
                right: auto;
                /* Let it position left/center */
                left: 50%;
                transform: translateX(-50%);
            }

            .tooltip-text::after {
                top: -10px;
                /* Position arrow at the top */
                bottom: auto;
                border-color: transparent transparent #333 transparent;
                /* Arrow pointing up */
            }

            #annotation-controls {
                text-align: left;
            }

            /* Left align on mobile */
            #annotation-controls button {
                margin-bottom: 0.5rem;
            }

            /* Stack buttons slightly */
        }

        #current-group-intro.drawn-on-canvas,
        #question-text.drawn-on-canvas {
            /* Text remains visible behind transparent canvas for annotation */
        }

        /* When annotation mode is active, text should remain visible behind canvas */
        #question-text.drawn-on-canvas {
            /* Text remains visible for annotation */
        }

        /* When annotation mode is active, hide the original text */
        #question-text.drawn-on-canvas {
            /* Text should remain visible behind transparent canvas */
        }

        /* Ensure the canvas is interactive when annotation mode is active */
        #annotationCanvas.annotation-active {
            pointer-events: auto;
        }

        /* Force text visibility in annotation mode only for elements with drawn-on-canvas class */
        #current-group-intro.drawn-on-canvas,
        #question-text.drawn-on-canvas {
            visibility: visible;
            display: block;
            opacity: 1 !important;
        }

        /* Ensure group intro with content is always visible */
        #current-group-intro.has-content {
            display: block !important;
        }

        /* Ensure group intro without drawn-on-canvas class stays hidden when empty */
        #current-group-intro:not(.drawn-on-canvas) {
            /* display: none !important; */
        }

        /* Timer Container Styles */
        #timer-container {
            display: flex;
            justify-content: flex-end;
            gap: 1rem;
            margin-bottom: 1rem;
            font-size: 0.9rem;
            color: var(--dark-gray);
        }

        .timer {
            display: flex;
            align-items: center;
            gap: 0.3rem;
            background-color: var(--light-gray);
            padding: 0.4rem 0.6rem;
            border-radius: var(--border-radius);
            border: 1px solid var(--border-color);
        }

        .timer-label {
            font-weight: 600;
        }

        .timer-value {
            font-family: monospace;
            font-size: 1.1em;
        }

        .timer.warning .timer-value {
            color: var(--warning-color);
            font-weight: bold;
        }

        .timer.danger .timer-value {
            color: var(--danger-color);
            font-weight: bold;
            animation: pulse 1s infinite;
        }

        @keyframes pulse {
            0% {
                opacity: 1;
            }

            50% {
                opacity: 0.5;
            }

            100% {
                opacity: 1;
            }
        }

        /* Timer Settings Styles */
        .setting-item {
            margin-bottom: 0.8rem;
        }

        .setting-item label {
            display: block;
            margin-bottom: 0.3rem;
        }

        .setting-item input[type="number"] {
            width: 100%;
            padding: 0.4rem;
            border: 1px solid var(--border-color);
            border-radius: var(--border-radius);
            font-size: 0.9rem;
        }

        /* Keep checkboxes on same line with label */
        .setting-item label input[type="checkbox"] {
            margin-right: 0.4rem;
            vertical-align: middle;
        }

        @keyframes flash {
            0% {
                opacity: 1;
            }

            50% {
                opacity: 0.5;
            }

            100% {
                opacity: 1;
            }
        }

        .timer.flashing {
            animation: flash 0.8s infinite;
            color: var(--danger-color) !important;
            font-weight: bold !important;
        }

        .timer.flashing .timer-value {
            color: var(--danger-color) !important;
        }

        /* --- Modal Styles --- */
        .modal {
            display: none;
            /* Hidden by default */
            position: fixed;
            /* Stay in place */
            z-index: 1002;
            /* Sit on top (above sidebar overlay) */
            left: 0;
            top: 0;
            width: 100%;
            /* Full width */
            height: 100%;
            /* Full height */
            overflow: auto;
            /* Enable scroll if needed */
            background-color: rgba(0, 0, 0, 0.5);
            /* Black w/ opacity */
            animation: fadeIn 0.3s ease-in-out;
            /* Simple fade-in */
        }

        @keyframes fadeIn {
            from {
                opacity: 0;
            }

            to {
                opacity: 1;
            }
        }

        .modal-content {
            background-color: #fefefe;
            margin: 10% auto;
            /* 10% from the top and centered */
            padding: 25px 30px;
            /* More padding */
            border: 1px solid #888;
            width: 85%;
            /* Responsive width */
            max-width: 700px;
            /* Max width */
            border-radius: var(--border-radius);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
            position: relative;
            animation: slideIn 0.3s ease-in-out;
            /* Simple slide-in */
        }

        @keyframes slideIn {
            from {
                transform: translateY(-30px);
                opacity: 0;
            }

            to {
                transform: translateY(0);
                opacity: 1;
            }
        }


        .modal-content h2 {
            margin-top: 0;
            color: var(--primary-color);
            border-bottom: 1px solid var(--border-color);
            padding-bottom: 0.75rem;
            margin-bottom: 1.5rem;
            font-size: 1.5rem;
            /* Larger title */
        }

        .close-button {
            color: #aaa;
            position: absolute;
            /* Position relative to modal-content */
            top: 10px;
            right: 15px;
            font-size: 28px;
            font-weight: bold;
            line-height: 1;
            /* Ensure tight spacing */
        }

        .close-button:hover,
        .close-button:focus {
            color: black;
            text-decoration: none;
            cursor: pointer;
        }

        #performance-stats-content ul {
            list-style: none;
            padding: 0;
            margin: 0;
        }

        #performance-stats-content li {
            padding: 0.6rem 0;
            /* Vertical spacing */
            border-bottom: 1px solid var(--medium-gray);
            /* Separator lines */
            font-size: 0.95rem;
        }

        #performance-stats-content li:last-child {
            border-bottom: none;
            /* Remove border from last item */
        }

        #performance-stats-content strong {
            display: inline-block;
            min-width: 200px;
            /* Align values */
            font-weight: 600;
            color: var(--dark-gray);
        }

        #performance-stats-content .category-stats {
            margin-top: 1.5rem;
            padding-top: 1rem;
            border-top: 2px solid var(--primary-color);
        }

        #performance-stats-content .category-stats h3 {
            margin-top: 0;
            margin-bottom: 0.75rem;
            font-size: 1.1rem;
            color: var(--primary-color);
        }

        /* Responsive Modal */
        @media (max-width: 767px) {
            .modal-content {
                width: 95%;
                margin: 15% auto;
                /* Adjust margin for mobile */
                padding: 20px;
            }

            #performance-stats-content strong {
                min-width: 150px;
                /* Adjust alignment for mobile */
            }

            .modal-content h2 {
                font-size: 1.3rem;
            }
        }

/* Styles for new category/subcategory filter in sidebar */
.category-filter-item {
    margin-bottom: 0.5rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.category-filter-item:last-child {
    border-bottom: none;
}

.main-category-line {
    display: flex;
    align-items: center;
    padding: 0.25rem 0;
}

.main-category-line label {
    flex-grow: 1;
    margin-bottom: 0;
}

.subcategory-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    line-height: 1;
    transition: all 0.2s ease;
}

.subcategory-list {
    margin-top: 0.25rem;
    margin-bottom: 0.5rem;
    padding-left: 1.5rem;
}

.subcategory-list li {
    margin-bottom: 0.25rem;
}

.subcategory-list label {
    display: flex;
    align-items: center;
}

.subcategory-list input[type="checkbox"] {
    margin-right: 0.5rem;
}

/* Additional styling for main category line */
.main-category-line input[type="checkbox"] {
    margin-right: 6px;
}

/* Additional styling for subcategory toggle - these will be overridden by inline styles */
.subcategory-toggle {
    user-select: none; /* Prevent text selection on click */
}

.subcategory-toggle:hover {
    background-color: #e0e0e0;
}

.subcategory-list {
    list-style-type: none;
    padding-left: 25px; /* Indentation for subcategories */
    margin-top: 4px;
    border-left: 1px dashed #ddd; /* Optional: visual guide for nesting */
}

.subcategory-list li {
    padding: 3px 0;
}

.subcategory-list label { /* Label for subcategory checkbox */
    display: flex;
    align-items: center;
    font-size: 0.95em;
}

.subcategory-list input[type="checkbox"] {
    margin-right: 6px;
}

/* Hide subcategory list by default if JS adds 'display: none;' */
/* No specific CSS needed for hiding if inline style is used, */
/* but a class-based approach would be: */
/* .subcategory-list.hidden { display: none; } */


/* Sidebar button styles */
.sidebar-button {
    display: inline-block;
    padding: 0.5rem 0.75rem;
    margin-bottom: 0.5rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: background-color 0.2s ease;
}

.sidebar-button:hover {
    background-color: var(--primary-hover-color);
}

/* Notification animations */
@keyframes slide-in {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes slide-out {
    from {
        transform: translateX(0);
        opacity: 1;
    }
    to {
        transform: translateX(100%);
        opacity: 0;
    }
}

/* Styles for subcategory performance display in modal */
.subcategory-performance-toggle {
    background-color: #e7f1ff; /* Light blue background */
    border: 1px solid #cce0ff;
    color: #0056b3; /* Darker blue text */
    padding: 4px 8px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9em;
    margin-left: 10px; /* Space from main category stats */
    margin-top: 5px; /* Space from main category line if it wraps */
    display: inline-block; /* Allow margin-top */
}

.subcategory-performance-toggle:hover {
    background-color: #d0e0f8;
}

.subcategory-performance-details {
    background-color: #fdfdfd; /* Slightly off-white background for details */
    border: 1px solid #eee;
    padding: 10px;
    margin-top: 5px;
    margin-left: 20px; /* Indent subcategory details */
    border-radius: 4px;
}

.subcategory-performance-details ul {
    list-style-type: none;
    padding-left: 10px; /* Further indent list items if needed */
    margin: 0;
}

.subcategory-performance-details li {
    padding: 4px 0;
    font-size: 0.95em;
    border-bottom: 1px dotted #f0f0f0; /* Separator for subcategory items */
}
.subcategory-performance-details li:last-child {
    border-bottom: none;
}