html, body {
    height: 100vh;
    margin: 0;
    padding: 0;
}

/* 自定义滚动条 */
.custom-scrollbar::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

.custom-scrollbar::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 4px;
}

.custom-scrollbar::-webkit-scrollbar-thumb {
    background: #c1c1c1;
    border-radius: 4px;
}

.custom-scrollbar::-webkit-scrollbar-thumb:hover {
    background: #a8a8a8;
}

/* 设置面板动画 */
@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

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

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes fadeOut {
    from { opacity: 1; }
    to { opacity: 0; }
}

.settings-panel {
    animation: slideIn 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.settings-panel.hiding {
    animation: slideOut 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.overlay-fade-in {
    animation: fadeIn 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.overlay-fade-out {
    animation: fadeOut 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 颜色选择器样式 */
.color-option {
    width: 24px;
    height: 24px;
    border-radius: 4px;
    cursor: pointer;
    transition: transform 0.2s;
    border: 2px solid transparent;
}

.color-option:hover {
    transform: scale(1.1);
}

.color-option.selected {
    border-color: #3b82f6;
    transform: scale(1.1);
}

/* 按钮选中样式 */
.style-button {
    transition: all 0.2s;
    position: relative;
    overflow: hidden;
}

.style-button.selected {
    background-color: #3b82f6;
    color: white;
    border-color: #3b82f6;
}

.style-button:hover {
    border-color: #3b82f6;
}

.highlight-text, #preview mark {
    background-color: rgba(255, 255, 0, 0.5);
    border-bottom: 2px solid rgba(255, 200, 0, 0.8);
    border-radius: 2px;
    padding: 0 2px;
    margin: 0 1px;
    transition: all 0.2s ease;
}

.tooltip {
    position: relative;
    display: inline-block;
}

.tooltip .tooltiptext {
    visibility: hidden;
    background-color: #333;
    color: #fff;
    text-align: center;
    border-radius: 4px;
    padding: 4px 8px;
    position: absolute;
    z-index: 1;
    top: calc(100% + 5px);
    left: 50%;
    transform: translateX(-50%);
    font-size: 12px;
    white-space: nowrap;
    opacity: 0;
    transition: opacity 0.2s;
}

/* 处理左侧边界问题 */
.tooltip:first-child .tooltiptext {
    left: 0;
    transform: none;
}

/* 添加小箭头 */
.tooltip .tooltiptext::before {
    content: "";
    position: absolute;
    bottom: 100%;
    left: 50%;
    margin-left: -5px;
    border-width: 5px;
    border-style: solid;
    border-color: transparent transparent #333 transparent;
}

/* 第一个 tooltip 的箭头位置调整 */
.tooltip:first-child .tooltiptext::before {
    left: 10px;
    margin-left: 0;
}

/* 工具栏右侧按钮样式 */
.toolbar-group:last-child button {
    width: auto;
    padding: 0 8px;
}

/* 工具栏右侧按钮组中倒数第二个按钮（复制按钮）的tooltip位置调整 */
.toolbar-group:last-child .tooltip:nth-last-child(2) .tooltiptext {
    right: -50%;
    left: auto;
    transform: none;
}

/* 倒数第二个按钮的tooltip箭头位置调整 */
.toolbar-group:last-child .tooltip:nth-last-child(2) .tooltiptext::before {
    right: 45%;
    left: auto;
    margin-left: 0;
}

.tooltip:hover .tooltiptext {
    visibility: visible;
    opacity: 1;
}

/* 工具栏样式（合并后） */
.md-toolbar {
    display: flex;
    justify-content: space-between;
    gap: 0.25rem;
    padding: 0.5rem;
    background-color: #f8f9fa;
    border-radius: 4px;
    margin-bottom: 0.5rem;
    position: relative;
    z-index: 2;
}

.md-toolbar button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    border: 1px solid #e2e8f0;
    background-color: white;
    color: #4a5568;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 14px;
}

.md-toolbar button:hover {
    background-color: #edf2f7;
    border-color: #cbd5e0;
}

.toolbar-group {
    display: flex;
    gap: 0.5rem;
}

.editor-container {
    display: flex;
    flex: 1;
    min-height: 0;
    position: relative;
    border: 1px solid #e2e8f0;
    border-radius: 4px;
}

.line-numbers {
    width: 40px;
    padding: 8px 0;
    background-color: #f8f9fa;
    border-right: 1px solid #e2e8f0;
    font-family: monospace;
    font-size: 14px;
    line-height: 1.5;
    text-align: center;
    white-space: pre;
    color: #94a3b8;
    user-select: none;
    overflow-y: hidden;
}

#editor {
    flex: 1;
    padding: 8px;
    border: none;
    font-family: monospace;
    font-size: 14px;
    line-height: 1.5;
    resize: none;
    overflow-y: auto;
}

#editor.drag-over {
    background-color: #e0f2fe;
}

.dark #editor.drag-over,
body.dark #editor.drag-over {
    background-color: #1e3a5f;
}

/* 最后一个tooltip（清空按钮）的位置调整 */
.tooltip:last-child .tooltiptext {
    right: 0;
    left: auto;
    transform: none;
}

/* 最后一个tooltip的箭头位置调整 */
.tooltip:last-child .tooltiptext::before {
    right: 10px;
    left: auto;
    margin-left: 0;
}

/* 预览区样式 */
#preview {
    padding: 1rem;
    line-height: 1.6;
    color: #24292e;
    overflow-y: auto;
}

/* PDF 打印样式 */
@media print {
    /* 打印时强制使用浅色主题 */
    body, body.dark, .dark {
        background-color: white !important;
    }

    /* 隐藏除预览区外的所有元素 */
    body * {
        visibility: hidden;
    }

    #preview, #preview * {
        visibility: visible;
    }

    #preview {
        position: absolute;
        left: 0;
        top: 0;
        width: 100%;
        padding: 20px;
        overflow: visible;
        border: none;
        background-color: white !important;
        color: #24292e !important;
    }

    /* 打印时表格使用浅色样式 */
    #preview th {
        background-color: #f6f8fa !important;
        color: #24292e !important;
    }

    #preview td {
        color: #24292e !important;
    }

    /* 打印时代码块使用浅色样式 */
    #preview pre {
        background-color: #f6f8fa !important;
    }

    #preview code {
        background-color: rgba(175, 184, 193, 0.2) !important;
        color: #24292e !important;
    }

    /* 分页控制 - 避免元素内部分页 */
    #preview p,
    #preview h1,
    #preview h2,
    #preview h3,
    #preview h4,
    #preview h5,
    #preview h6,
    #preview li,
    #preview img,
    #preview pre,
    #preview code,
    #preview blockquote,
    #preview figure,
    #preview tr {
        break-inside: avoid;
        page-break-inside: avoid;
    }

    /* 标题后不分页，保持与下文连贯 */
    #preview h1,
    #preview h2,
    #preview h3,
    #preview h4,
    #preview h5,
    #preview h6 {
        break-after: avoid;
        page-break-after: avoid;
    }

    /* 段落孤行/寡行控制 */
    #preview p {
        orphans: 3;
        widows: 3;
    }

    /* 表格尽量不分页 */
    #preview table {
        break-inside: avoid;
        page-break-inside: avoid;
    }
}

/* 状态栏样式 */
.status-bar {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 4px 8px;
    font-size: 12px;
    color: #6b7280;
    background-color: #f9fafb;
    border-top: 1px solid #e5e7eb;
    border-radius: 0 0 4px 4px;
}

.status-divider {
    color: #d1d5db;
}

/* 深色模式 */
.dark {
    --bg-primary: #1f2937;
    --bg-secondary: #111827;
    --bg-tertiary: #374151;
    --text-primary: #f9fafb;
    --text-secondary: #d1d5db;
    --text-muted: #9ca3af;
    --border-color: #4b5563;
}

.dark body,
body.dark {
    background-color: var(--bg-secondary);
}

.dark nav,
body.dark nav {
    background-color: var(--bg-primary);
    border-color: var(--border-color);
}

.dark nav .text-gray-800,
body.dark nav .text-gray-800 {
    color: var(--text-primary);
}

.dark nav a,
.dark nav button,
body.dark nav a,
body.dark nav button {
    background-color: var(--bg-tertiary);
    color: var(--text-secondary);
}

.dark nav a:hover,
.dark nav button:hover,
body.dark nav a:hover,
body.dark nav button:hover {
    background-color: var(--border-color);
}

.dark .bg-white,
body.dark .bg-white {
    background-color: var(--bg-primary);
}

.dark .bg-gray-100,
body.dark .bg-gray-100 {
    background-color: var(--bg-secondary);
}

.dark #editor,
body.dark #editor {
    background-color: var(--bg-primary);
    color: var(--text-primary);
}

.dark #editor::placeholder,
body.dark #editor::placeholder {
    color: var(--text-muted);
}

.dark .line-numbers,
body.dark .line-numbers {
    background-color: var(--bg-tertiary);
    border-color: var(--border-color);
    color: var(--text-muted);
}

.dark .editor-container,
body.dark .editor-container {
    border-color: var(--border-color);
}

.dark #preview,
body.dark #preview {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    border-color: var(--border-color);
}

.dark .md-toolbar,
body.dark .md-toolbar {
    background-color: var(--bg-tertiary);
}

.dark .md-toolbar button,
body.dark .md-toolbar button {
    background-color: var(--bg-primary);
    color: var(--text-secondary);
    border-color: var(--border-color);
}

.dark .md-toolbar button:hover,
body.dark .md-toolbar button:hover {
    background-color: var(--bg-tertiary);
}

.dark .md-toolbar h2,
body.dark .md-toolbar h2 {
    color: var(--text-primary);
}

.dark .status-bar,
body.dark .status-bar {
    background-color: var(--bg-tertiary);
    border-color: var(--border-color);
    color: var(--text-muted);
}

.dark .status-divider,
body.dark .status-divider {
    color: var(--border-color);
}

.dark .shadow-lg,
body.dark .shadow-lg {
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -2px rgba(0, 0, 0, 0.2);
}

.dark #settingsPanel,
body.dark #settingsPanel {
    background-color: var(--bg-primary);
}

.dark #settingsPanel h3,
.dark #settingsPanel label,
body.dark #settingsPanel h3,
body.dark #settingsPanel label {
    color: var(--text-primary);
}

.dark #settingsPanel input,
body.dark #settingsPanel input {
    background-color: var(--bg-tertiary);
    border-color: var(--border-color);
    color: var(--text-primary);
}

.dark #settingsPanel .style-button,
body.dark #settingsPanel .style-button {
    background-color: var(--bg-tertiary);
    border-color: var(--border-color);
    color: var(--text-secondary);
}

.dark #settingsPanel .border-b,
.dark #settingsPanel .border-t,
body.dark #settingsPanel .border-b,
body.dark #settingsPanel .border-t {
    border-color: var(--border-color);
}

.dark #resetSettings,
body.dark #resetSettings {
    background-color: var(--bg-tertiary);
    color: var(--text-secondary);
}

.dark .custom-scrollbar::-webkit-scrollbar-track,
body.dark .custom-scrollbar::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
}

.dark .custom-scrollbar::-webkit-scrollbar-thumb,
body.dark .custom-scrollbar::-webkit-scrollbar-thumb {
    background: var(--border-color);
}

/* 代码高亮样式 */
#preview pre {
    background-color: #f6f8fa;
    border-radius: 6px;
    padding: 16px;
    margin: 1em 0;
    white-space: pre-wrap;
    word-wrap: break-word;
    overflow-wrap: break-word;
}

#preview pre code {
    background: none;
    padding: 0;
    font-size: 14px;
    line-height: 1.5;
    white-space: pre-wrap;
    word-wrap: break-word;
}

#preview code {
    background-color: rgba(175, 184, 193, 0.2);
    padding: 0.2em 0.4em;
    border-radius: 3px;
    font-size: 85%;
    font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
}

.dark #preview pre,
body.dark #preview pre {
    background-color: #161b22;
}

.dark #preview code,
body.dark #preview code {
    background-color: rgba(110, 118, 129, 0.4);
}

/* 侧边栏折叠 */
.sidebar-collapsed {
    width: 0 !important;
    min-width: 0 !important;
    padding: 0 !important;
    overflow: hidden !important;
    border: none !important;
}

/* 分栏拖拽 */
#splitDivider {
    position: relative;
    z-index: 5;
}
#splitDivider::after {
    content: '';
    position: absolute;
    left: 2px;
    top: 50%;
    width: 4px;
    height: 32px;
    background: #cbd5e1;
    border-radius: 2px;
    transform: translateY(-50%);
    opacity: 0;
    transition: opacity 0.2s;
}
#splitDivider:hover::after,
#splitDivider.active::after {
    opacity: 1;
}
body.dark #splitDivider::after {
    background: #475569;
}

/* 预览隐藏模式 */
#editorPanel.panel-hidden {
    display: none !important;
}
#previewPanel.panel-hidden {
    display: none !important;
}

/* 全屏预览浮层 */
#previewFullscreen {
    animation: fadeIn 0.2s ease;
}
body.dark #previewFullscreen {
    background-color: var(--bg-primary);
    color: var(--text-primary);
}
body.dark #previewFullscreen .border-b {
    border-color: var(--border-color);
}

/* 书签样式 */
#bookmarkList div:hover {
    background-color: #f3f4f6;
}
body.dark #bookmarkList div:hover {
    background-color: var(--bg-tertiary);
}
#bookmarkSection .border-t {
    border-color: #e5e7eb;
}

/* Mermaid 流程图兼容 */
.mermaid {
    text-align: center;
    margin: 1em 0;
    overflow-x: auto;
}
.mermaid svg {
    max-width: 100%;
    height: auto;
}

/* 只读模式 */
body.readonly #editor {
    background-color: #f9fafb;
    cursor: default;
}
body.dark.readonly #editor {
    background-color: #1a1f2e;
}
body.readonly #editor:focus {
    outline: none;
    ring: none;
}
body.readonly .md-toolbar button:not(#previewToggle):not(#fullscreenPreviewBtn):not(#copyHtmlBtn):not(#generatePdfBtn):not(#generateImageBtn) {
    display: none;
}
body.readonly #addChapterBtn,
body.readonly #addChapterSideBtn,
body.readonly #importMdBtn,
body.readonly #openFolderBtn,
body.readonly #saveMdBtn,
body.readonly #copyBtn {
    display: none !important;
}
body.readonly .chapter-move,
body.readonly .chapter-actions {
    display: none !important;
}
body.readonly #settingsBtn,
body.readonly [onclick*="showSettings"] {
    display: none !important;
}

/* 深色模式表格样式 */
.dark #preview table,
body.dark #preview table {
    border-color: var(--border-color);
}

.dark #preview th,
body.dark #preview th {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    border-color: var(--border-color);
}

.dark #preview td,
body.dark #preview td {
    border-color: var(--border-color);
    color: var(--text-primary);
}

.dark #preview tr:nth-child(even),
body.dark #preview tr:nth-child(even) {
    background-color: var(--bg-tertiary);
}

/* ── 快捷键面板 ── */
#shortcutsModal table tr:last-child { border: none; }

/* ── 高亮标记 ── */
.mark-highlight { border-radius: 2px; padding: 0 2px; cursor: pointer; }
.mark-highlight:hover { filter: brightness(0.9); }
.highlight-toolbar-btn { width: 20px; height: 20px; border-radius: 3px; cursor: pointer; border: 1px solid #d1d5db; }
.highlight-toolbar-btn:hover { transform: scale(1.15); }
#highlightToolbar { box-shadow: 0 4px 12px rgba(0,0,0,0.15); }

/* ── 批注标记 ── */
.annotation-indicator { display: inline-block; width: 8px; height: 8px; background: #3b82f6; border-radius: 50%; cursor: pointer; vertical-align: super; font-size: 8px; margin: 0 2px; }
.annotation-indicator:hover { transform: scale(1.5); }
.annotation-popup-note { font-size: 12px; line-height: 1.4; }

/* ── 聚焦模式 ── */
body.focus-mode #editor {
    background: transparent;
    transition: background 0.3s;
}
body.focus-mode #editor::selection { background: #93c5fd; }
body.focus-mode .line-numbers { opacity: 0.3; }
body.focus-mode #editor {
    --focus-bg: rgba(255,255,255,0.03);
    background-image: linear-gradient(transparent calc(100% - 1.5em), rgba(59,130,246,0.06) calc(100% - 1.5em));
    background-size: 100% 1.5em;
}
body.dark.focus-mode #editor {
    background-image: linear-gradient(transparent calc(100% - 1.5em), rgba(96,165,250,0.08) calc(100% - 1.5em));
    background-size: 100% 1.5em;
}

/* ── 打字机模式 ── */
body.typewriter-mode .editor-container {
    scroll-behavior: smooth;
}

/* ── 演示模式 ── */
#presentOverlay { background: #111827; color: #f3f4f6; }
#presentSlide { font-size: 1.2em; line-height: 1.8; }
#presentSlide h1 { font-size: 2.5em; text-align: center; margin: 1em 0 0.5em; color: #f9fafb; border: none; }
#presentSlide h2 { font-size: 1.8em; margin: 1.5em 0 0.5em; color: #e5e7eb; border-bottom-color: #374151; }
#presentSlide h3 { font-size: 1.4em; color: #d1d5db; }
#presentSlide p { color: #d1d5db; text-indent: 2em; }
#presentSlide pre { background: #1f2937; border: 1px solid #374151; }
#presentSlide code { background: #1f2937; color: #93c5fd; }
#presentSlide blockquote { border-left-color: #3b82f6; color: #9ca3af; }
#presentSlide table { border-color: #374151; }
#presentSlide th, #presentSlide td { border-color: #374151; color: #d1d5db; }
#presentSlide th { background: #1f2937; }
#presentSlide li { color: #d1d5db; }

/* ── TTS 朗读 ── */
#ttsBar { flex-shrink: 0; }
#ttsBar button:active { transform: scale(0.95); }
body.dark #ttsBar { background-color: var(--bg-tertiary); border-color: var(--border-color); }
body.dark #ttsBar span { color: var(--text-muted); }

/* ── 代码沙盒 ── */
.sandbox-wrapper { margin: 0.5em 0; }
.sandbox-btn { display: inline-flex; align-items: center; gap: 0.25rem; margin-bottom: 0.5rem; }
.sandbox-btn:active { transform: scale(0.95); }
.sandbox-output {
    background: #1e293b;
    color: #e2e8f0;
    padding: 0.75em 1em;
    border-radius: 4px;
    font-family: monospace;
    font-size: 13px;
    line-height: 1.5;
    overflow-x: auto;
    white-space: pre-wrap;
    min-height: 2em;
    max-height: 300px;
    overflow-y: auto;
}
body.dark .sandbox-output { background: #0f172a; }

/* ── 标题锚点 ── */
.heading-anchor { opacity: 0; transition: opacity 0.15s; text-decoration: none !important; margin-left: 0.3em; }
h1:hover .heading-anchor, h2:hover .heading-anchor, h3:hover .heading-anchor, h4:hover .heading-anchor { opacity: 1; }
body.dark .heading-anchor { color: #4b5563; }
body.dark .heading-anchor:hover { color: #60a5fa; }

/* ── 侧边栏右键菜单 ── */
#sidebarContextMenu { min-width: 140px; z-index: 100; }
body.dark #sidebarContextMenu { background-color: var(--bg-primary); border-color: var(--border-color); color: var(--text-primary); }
body.dark #sidebarContextMenu div:hover { background-color: var(--bg-tertiary); }

/* ── AI 对话面板 ── */
#aiChatPanel { animation: slideIn 0.2s ease; }
#aiChatPanel textarea { min-height: 2.5em; max-height: 6em; }
#aiChatMessages .bg-purple-500 { white-space: pre-wrap; word-break: break-word; }
#aiChatMessages .bg-gray-100 { white-space: pre-wrap; word-break: break-word; }
body.dark #aiChatPanel { background-color: var(--bg-primary); color: var(--text-primary); }
body.dark #aiChatPanel .border-b, body.dark #aiChatPanel .border-t { border-color: var(--border-color); }
body.dark #aiChatMessages .bg-gray-100 { background-color: var(--bg-tertiary); color: var(--text-primary); }
body.dark #aiChatInput { background-color: var(--bg-tertiary); color: var(--text-primary); border-color: var(--border-color); }
body.dark #aiChatContext { background-color: var(--bg-tertiary); color: var(--text-muted); }
body.dark .ai-prompt-btn { background-color: var(--bg-tertiary); color: var(--text-secondary); }
body.dark .ai-prompt-btn:hover { background-color: var(--border-color); }

/* ── 讲解录制面板 ── */
#lecturePanel { animation: fadeIn 0.2s ease; box-shadow: 0 4px 20px rgba(0,0,0,0.15); }
body.dark #lecturePanel { background-color: var(--bg-primary); border-color: var(--border-color); }
body.dark #lecturePanel .text-gray-500 { color: var(--text-muted); }
body.dark #lecturePanel .text-gray-600 { color: var(--text-secondary); }

/* ══════════════════════════════════════════════════
   移动端适配 — 响应式布局
   ══════════════════════════════════════════════════ */

/* 小屏/平板：隐藏桌面提示、调整边距 */
@media (max-width: 1024px) {
    #bookTitleDisplay { max-width: 120px; }
}

/* 平板竖屏 & 大屏手机 */
@media (max-width: 768px) {
    /* 顶部导航栏：按钮折叠，只留图标 */
    nav .gap-1\.5 { gap: 0.25rem; }
    nav .px-3 { padding-left: 0.5rem; padding-right: 0.5rem; }
    nav .py-1\.5 { padding-top: 0.375rem; padding-bottom: 0.375rem; }
    nav button { font-size: 11px; }
    nav .hidden\:sm\:inline { display: none; }

    /* 侧边栏：改为滑出式抽屉 */
    #sidebar {
        position: fixed !important;
        top: 0 !important;
        left: 0 !important;
        bottom: 0 !important;
        width: 280px !important;
        max-width: 80vw !important;
        z-index: 30 !important;
        transform: translateX(-100%) !important;
        transition: transform 0.25s cubic-bezier(0.4, 0, 0.2, 1) !important;
        border-right: 1px solid #e5e7eb;
        box-shadow: 4px 0 20px rgba(0,0,0,0.15);
    }
    #sidebar.sidebar-open {
        transform: translateX(0) !important;
    }
    /* 桌面折叠类名在移动端无效 */
    #sidebar.sidebar-collapsed {
        width: 280px !important;
        min-width: 280px !important;
        padding: inherit !important;
        overflow: auto !important;
        border: inherit !important;
        transform: translateX(-100%) !important;
    }
    #sidebar.sidebar-collapsed.sidebar-open {
        transform: translateX(0) !important;
    }

    /* 侧边栏遮罩 */
    #sidebarOverlay {
        display: none !important;
    }
    #sidebarOverlay.sidebar-open {
        display: block !important;
    }

    /* 内容区域在移动端全宽 */
    #mainContent { padding: 0.375rem; }

    /* 图表设置面板全屏 */
    #settingsPanel { width: 100vw !important; }
}

/* 手机 */
@media (max-width: 640px) {
    /* 分栏堆叠：编辑器在上，预览在下 */
    #splitContainer {
        flex-direction: column !important;
    }
    #splitDivider {
        display: none !important;
    }
    #editorPanel, #previewPanel {
        flex: 1 1 50% !important;
        min-width: 0 !important;
        min-height: 0 !important;
        max-height: 50%;
    }
    #editorPanel.panel-hidden { display: none !important; }
    #previewPanel.panel-hidden { display: none !important; }
    #previewPanel.panel-hidden + #editorPanel { max-height: 100%; }

    /* 顶部栏：紧凑 */
    nav .gap-1\.5 { gap: 0.125rem; }
    nav .px-3 { padding-left: 0.25rem; padding-right: 0.25rem; }
    #bookTitleDisplay { max-width: 80px; font-size: 12px; }

    /* 编辑器工具栏：横向滚动 */
    .md-toolbar {
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        gap: 0;
    }
    .md-toolbar .toolbar-group {
        flex-shrink: 0;
    }
    .md-toolbar button { font-size: 12px; padding: 0.2rem 0.35rem; }

    /* 预览区工具栏折叠 */
    #previewPanel .md-toolbar .toolbar-group:last-child {
        flex-wrap: nowrap;
    }
    #previewPanel .md-toolbar .toolbar-group:last-child button {
        font-size: 11px;
        padding: 0.15rem 0.3rem;
    }
    #previewPanel .md-toolbar .toolbar-group:last-child button span {
        display: none;
    }
    #previewPanel .md-toolbar h2 { font-size: 13px; }

    /* AI 对话面板全屏 */
    #aiChatPanel { width: 100vw !important; }

    /* 快捷键面板全屏 */
    #shortcutsModal > div { width: 100vw !important; max-width: 100vw !important; height: 100vh; border-radius: 0; }
    #shortcutsModal table { font-size: 13px; }

    /* 书籍信息弹窗全屏 */
    #bookMetaModal > div { width: 100vw !important; max-width: 100vw !important; height: 100vh; border-radius: 0; overflow-y: auto; }
    #bookMetaModal > div .mt-4 { margin-bottom: 2rem; }

    /* 讲解面板：底部全宽 */
    #lecturePanel { left: 0; right: 0; bottom: 0; width: 100% !important; border-radius: 0 !important; }

    /* 状态栏精简 */
    .status-bar { font-size: 10px; gap: 4px; flex-wrap: wrap; }
    .status-bar .truncate { max-width: 100px; }
    .status-bar .status-divider + span { display: none; }
    .status-bar .status-divider:nth-child(4) { display: none; }
    .status-bar .status-divider:nth-child(5) ~ .status-divider { display: none; }

    /* 预览全屏 */
    #previewFullscreen > div:first-child span { font-size: 12px; }
    #previewFullscreen #previewFullscreenContent { padding: 1rem; }

    /* 演示模式 */
    #presentContent { padding: 1rem; }
    #presentSlide h1 { font-size: 1.8em; }
    #presentSlide h2 { font-size: 1.4em; }
    #presentSlide { font-size: 1em; }
}

/* 小手机 */
@media (max-width: 480px) {
    nav .gap-1\.5 { gap: 0; }
    #bookTitleDisplay { max-width: 60px; font-size: 11px; }
    nav button { font-size: 10px; padding: 0.2rem 0.25rem; }
    #editor { font-size: 13px; }
    #preview { padding: 0.5rem; font-size: 14px; }
    .custom-scrollbar::-webkit-scrollbar { width: 4px; height: 4px; }
    #previewPanel .md-toolbar .toolbar-group:last-child button {
        padding: 0.1rem 0.2rem;
        font-size: 10px;
    }
    #ttsBar { flex-wrap: wrap; }
    #ttsBar input[type="range"] { width: 48px; }
}

/* ── 深色模式移动端 ── */
body.dark #sidebar { border-right-color: var(--border-color); }
body.dark #sidebarOverlay { background-color: rgba(0,0,0,0.6); }

/* ── 触摸优化 ── */
@media (hover: none) and (pointer: coarse) {
    /* 增大导航栏按钮点击区域 */
    nav button, .md-toolbar button, #previewPanel .md-toolbar button {
        min-height: 32px;
        min-width: 32px;
    }
    /* 侧边栏按钮更大 */
    .sidebar-actions button {
        padding-top: 0.5rem !important;
        padding-bottom: 0.5rem !important;
    }
    /* 侧边栏章节项更高 */
    .chapter-item {
        padding-top: 0.5rem !important;
        padding-bottom: 0.5rem !important;
    }
    /* 隐藏 hover-only 效果（hover 在触摸设备上粘滞） */
    .chapter-actions { opacity: 1 !important; }
    .chapter-move { opacity: 1 !important; }
    .heading-anchor { opacity: 1 !important; }
    .group-hover\:opacity-100 { opacity: 1 !important; }
    /* 拖拽排序按钮在触屏上显示，但视觉弱化 */
    .chapter-move { color: #d1d5db; }
    /* 预览区工具栏文字总是显示 */
    #previewPanel .md-toolbar .toolbar-group:last-child button span { display: inline !important; }
    #previewPanel .md-toolbar .toolbar-group:last-child button { font-size: 11px; }
    /* 移除 hover 缩放效果 */
    .color-option:hover { transform: none; }
    .highlight-toolbar-btn:hover { transform: none; }
    .chapter-item:hover { background-color: inherit; }
    .chapter-item:active { opacity: 0.7; }
    /* 高亮工具栏：增大触控区域 */
    #highlightToolbar button { min-width: 28px; min-height: 28px; }
    #highlightToolbar [data-color] { width: 24px; height: 24px; }
}

/* ── 窗口 resize 联动 ── */
@media (max-width: 640px) {
    .sidebar-actions .btn-label { display: inline !important; }
}