/* Reader component motion and overflow tokens. */
/* Markdown content, reader controls, search, typography, and custom scrollbar. */
        .markdown-content {
            padding: 0px; line-height: 1.7; 
            font-size: calc(var(--base-font-size) * var(--font-scale)); 
            color: var(--text-color);
            text-align: left; user-select: text;
            max-width: 1000px;
            width: 100%;
            margin: 0 auto;
            overflow-wrap: anywhere; 
            word-break: break-word;
            word-wrap: break-word;
            box-sizing: border-box;
        }

        .markdown-content * {
            overflow-wrap: anywhere;
            word-break: break-word;
            box-sizing: border-box;
        }
        
        .markdown-content h1, .markdown-content h2, .markdown-content h3 { color: var(--text-color); margin-top: 1.5em; margin-bottom: 0.5em; font-weight: 700; line-height: 1.3; }
        .markdown-content h1 { font-size: 1.6em; border-bottom: 1px solid var(--border-color); padding-bottom: 0.3em; }
        .markdown-content h2 { font-size: 1.4em; }
        .markdown-content p { margin-bottom: 1em; white-space: normal; }
        .markdown-content ul, .markdown-content ol { padding-left: 20px; margin-bottom: 1em; }
        .markdown-content li { margin-bottom: 0.5em; white-space: normal; }
        .markdown-content code { background: var(--bg-color); padding: 2px 4px; border-radius: 4px; font-family: monospace; font-size: 0.9em; word-break: break-all;}

        .markdown-content pre { 
            background: var(--bg-color); padding: 10px; border-radius: 8px; 
            overflow-x: auto; margin-bottom: 1em; 
            white-space: pre; 
            max-width: 100%;
        }
        .markdown-content pre code { background: none; padding: 0; word-break: normal; overflow-wrap: normal; white-space: pre; }
        .markdown-content blockquote { border-left: 4px solid var(--primary-color); margin: 0; padding-left: 15px; color: var(--sub-text-color); margin-bottom: 1em; }

        .markdown-content table { 
            border-collapse: collapse; 
            width: 100%; 
            display: block;
            overflow-x: auto;
            -webkit-overflow-scrolling: touch;
            margin-bottom: 1em;
            max-width: 100%;
        }

        .markdown-content th, .markdown-content td { 
            border: 1px solid var(--border-color); padding: 8px; text-align: left; white-space: nowrap; 
            font-size: calc(var(--base-font-size) * var(--font-scale));
        }
        .markdown-content th { background-color: var(--bg-color); font-weight: 600; }

        @media (min-width: 768px) {
             .markdown-content table { display: table; }
             .markdown-content th, .markdown-content td { white-space: normal; }
        }

        .markdown-content img { max-width: 100%; height: auto; border-radius: 8px; margin: 10px 0; }

        .search-bar-overlay {
            position: absolute; top: 0; left: 0; right: 0;
            background: var(--card-bg); padding: 10px;
            border-bottom: 1px solid var(--border-color);
            display: flex; gap: 8px; align-items: center;
            z-index: var(--z-control);

            transform: translateY(-100%);
            opacity: 0;
            pointer-events: none;

            transition: transform 0.3s cubic-bezier(0.25, 0.8, 0.25, 1), opacity 0.3s ease;
            box-shadow: 0 4px 10px rgba(0,0,0,0.05);
        }
        
        .search-bar-overlay.visible { 
            transform: translateY(0); 
            opacity: 1; 
            pointer-events: auto; 
        }
        
        .search-input-group {
            flex: 1; min-width: 0; display: flex; align-items: center; position: relative;
        }
        .search-input {
            width: 100%; min-width: 0; box-sizing: border-box; padding: 8px 64px 8px 12px; border-radius: 6px;
            border: 1px solid var(--border-color); background: var(--bg-color);
            color: var(--text-color); outline: none; font-size: 14px;
        }
        .search-input:focus { border-color: var(--primary-color); }
        .search-count {
            position: absolute; right: 8px; font-size: 12px; color: var(--sub-text-color);
            pointer-events: none;
        }
        
        .search-actions { display: flex; gap: 4px; }
        .search-btn {
            background: none; border: none; cursor: pointer; display: flex; align-items: center; justify-content: center;
            color: var(--sub-text-color); padding: 6px; border-radius: 4px; transition: background 0.2s;
            width: 44px; height: 44px; flex: none;
        }
        .search-btn:hover { background: var(--bg-color); color: var(--text-color); }
        .search-btn:active { background: var(--border-color); }
        .search-btn:disabled { opacity: 0.3; cursor: default; }
        
        mark.search-match { background-color: var(--search-match-bg); color: var(--search-match-text); padding: 2px 0; border-radius: 2px; }
        mark.search-match.active { background-color: var(--search-active-bg); color: var(--search-active-text); }

        .font-settings-overlay {
            position: absolute; 
            bottom: 60px;
            right: 5px; 
            background: var(--card-bg);
            padding: 15px; border-radius: 12px;
            box-shadow: 0 5px 20px rgba(0,0,0,0.15);
            border: 1px solid var(--border-color);
            display: flex; align-items: center; gap: 10px;
            z-index: var(--z-toast);
            width: 240px;

            transform: translateY(5px) scale(1);
            opacity: 0;
            pointer-events: none;

            transition: transform 0.25s cubic-bezier(0.25, 0.8, 0.25, 1), opacity 0.25s ease;
        }
        
        .font-settings-overlay.visible { 
            transform: translateY(0) scale(1);
            opacity: 1; 
            pointer-events: auto; 
            right: 5px;
            bottom: 60px;

        }

        .font-settings-overlay::after {
            content: ''; position: absolute; bottom: -6px; right: 25px;
            width: 10px; height: 10px; background: var(--card-bg);
            border-bottom: 1px solid var(--border-color); border-right: 1px solid var(--border-color);
            transform: rotate(45deg);
        }

        .font-slider-container { flex: 1; display: flex; align-items: center; gap: 8px; position: relative; }
        .font-icon-small, .font-icon-large { display: inline-flex; flex: none; align-items: center; color: var(--sub-text-color); }
        .font-icon-large { color: var(--text-color); }
        .font-range-track { position: relative; flex: 1; min-width: 0; }
        .font-range-input:focus-visible { outline: 2px solid var(--icon-focus-color); outline-offset: 6px; }
        
        .font-range-input {
            -webkit-appearance: none; display: block; margin: 0; width: 100%; height: 4px; border-radius: 2px; background: var(--border-color);
            outline: none; position: relative; z-index: 2;
        }
        .font-range-input::-webkit-slider-thumb {
            -webkit-appearance: none; width: 18px; height: 18px; border-radius: 50%;
            background: var(--card-bg); border: 2px solid var(--primary-color);
            cursor: pointer; box-shadow: 0 1px 3px rgba(0,0,0,0.2);
            transition: transform 0.1s;
        }
        .font-range-input::-webkit-slider-thumb:active { transform: scale(1.1); }

        .slider-mark-center {
            position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%);
            width: 2px; height: 10px; background-color: var(--sub-text-color);
            opacity: 0.3; z-index: 1; pointer-events: none;
        }

        .custom-scrollbar-container {
            position: absolute; right: 4px; top: 10px; bottom: 10px; width: 14px;
            z-index: var(--z-scrollbar); display: none; flex-direction: column; align-items: center;
        }
        .reader-mode .custom-scrollbar-container { display: flex; }
        
        .custom-scrollbar-track {
            position: relative; width: 2px; height: 100%; background: var(--border-color); border-radius: 2px;
        }
        
        .scroll-marker {
            --marker-size: 4px; --marker-emphasis-size: 6px;
            position: absolute; left: 50%; transform: translateX(-50%) translateY(-50%);
            width: var(--marker-size); height: var(--marker-size); border-radius: 50%;
            background-color: var(--border-color); border: 0;
            padding: 0; appearance: none;
            cursor: pointer; z-index: 2; transition: width 0.2s, height 0.2s, background-color 0.2s;
        }
        .scroll-marker:hover { width: var(--marker-emphasis-size); height: var(--marker-emphasis-size); background-color: var(--icon-accent-color); }
        .scroll-marker.active { background-color: var(--icon-accent-color); width: var(--marker-emphasis-size); height: var(--marker-emphasis-size); }
        .scroll-marker:focus-visible { outline: 2px solid var(--icon-accent-color); outline-offset: 2px; }
        
        .scroll-thumb {
            position: absolute; left: 50%; transform: translateX(-50%);
            width: 6px; height: 30px; background-color: var(--sub-text-color);
            border-radius: 4px; cursor: grab; z-index: 3; opacity: 0.5;
            transition: opacity 0.2s, background-color 0.2s;
        }
        .scroll-thumb:hover, .scroll-thumb.dragging { opacity: 0.9; width: 10px; }
        .scroll-thumb:active { cursor: grabbing; }

        .scroll-preview-box {
            position: absolute; 
            right: 25px; top: 0;
            width: 200px; height: 60px;
            pointer-events: none;
            opacity: 0; transform: scale(0.9);
            transition: opacity 0.2s, transform 0.2s;
            display: flex; align-items: center; justify-content: flex-end;
            z-index: var(--z-preview);
            perspective: 500px;
        }
        .scroll-preview-box.visible { opacity: 1; transform: scale(1); }
        
        .scroll-preview-wheel {
            position: relative; width: 100%; height: 100%;
            transform-style: preserve-3d;
        }
        
        .preview-item {
            position: absolute; right: 0; width: 100%; height: 20px;
            text-align: right;
            font-size: 12px; color: var(--sub-text-color);
            white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
            transform-origin: center right;
            backface-visibility: hidden;
            transition: transform 0.2s ease-out, opacity 0.2s ease-out;
            display: flex; align-items: center; justify-content: flex-end;
        }
        
        .preview-item.prev { top: 0; opacity: 0.4; transform: translateY(-5px) rotateX(25deg) scale(0.9); }
        .preview-item.curr { top: 20px; opacity: 1; color: var(--text-color); font-weight: bold; transform: translateY(0) rotateX(0) scale(1.05); text-shadow: 0 1px 5px var(--card-bg); }
        .preview-item.next { top: 40px; opacity: 0.4; transform: translateY(5px) rotateX(-25deg) scale(0.9); }
        
        .preview-text-bg { background: var(--card-bg); padding: 2px 6px; border-radius: 4px; box-shadow: 0 2px 8px rgba(0,0,0,0.1); border: 1px solid var(--border-color); max-width: 100%; overflow: hidden; text-overflow: ellipsis; }

        body.reader-mode .card {
            max-width: 96%;
            width: 96%;
            height: 94%;
            max-height: 94vh;
            padding-right: 0px; 
        }
        @media (min-width: 1600px) {
            body.reader-mode .card {
                max-width: 1500px;
            }
        }

        @media (max-width: 600px) {
            body.reader-mode .card { 
                width: 92%; max-width: 92%; 
                padding-right: 0; padding-bottom: 20px; 
                overflow: hidden;
            }
            .card-body-scroll {
            overflow-x: hidden;
            scroll-behavior: auto !important;
        }
            .markdown-content { 
                font-size: calc(14px * var(--font-scale)); 
                padding: 0 4px; 
            }
            .custom-scrollbar-container { width: 8px; right: 2px; }
            .scroll-marker { --marker-size: 3px; --marker-emphasis-size: 4px; }
            .scroll-thumb { width: 4px; }
            .scroll-preview-box { width: 160px; right: 15px; }
        }

        body.reader-mode .quiz-only {
            display: none !important;
        }
.search-bar-overlay,
.font-settings-overlay,
.scroll-preview-box {
  transition-duration: var(--duration-normal);
}

.markdown-content table,
.table-responsive-wrapper {
  max-width: 100%;
}