/* ============================================================
   SMP EXTRA LATEX — MATHCHA-STYLE MODERN UI
   Document-Centric + Top Ribbon + Left Tool Palette + Export Drawer
   ============================================================ */

body { overflow-x: hidden; }

:root {
    --body-bg: #0b1111;
    --widget-title-color: #fff;
    --exam-paper-bg: rgba(255,255,255,0.025);
    --exam-text-color: #ddd;
    --exam-bold-color: #f4f4f4;
    --exam-title-color: #f0f0f0;
    --accent-cyan: #5ce1e6;
    --accent-gold: #c9a96e;

    /* Workspace Canvas Tokens */
    --el-bg: #101216;
    --el-sheet-bg: #181b22;
    --el-sheet-border: rgba(92, 225, 230, 0.25);
    --el-sheet-shadow: 0 16px 48px rgba(0, 0, 0, 0.6);
    --el-ribbon-bg: #14171e;
    --el-ribbon-border: rgba(92, 225, 230, 0.16);
    --el-palette-bg: #14171e;
    --el-palette-border: rgba(92, 225, 230, 0.16);
    --el-btn-hover: rgba(92, 225, 230, 0.15);
    --el-btn-active: rgba(92, 225, 230, 0.25);
    --el-dot-color: rgba(92, 225, 230, 0.2);
    --el-grid-color: rgba(255, 255, 255, 0.05);

    /* Block Tokens */
    --el-block-bg: rgba(255, 255, 255, 0.03);
    --el-block-border: transparent;
    --el-block-hover-border: rgba(92, 225, 230, 0.35);
    --el-block-selected-border: var(--accent-cyan);
    --el-block-selected-shadow: 0 0 16px rgba(92, 225, 230, 0.3);

    /* Bubble & Popover */
    --el-popover-bg: #0f172a;
    --el-popover-border: #334155;
    --el-popover-text: #f1f5f9;
}

body:not(.dark-mode) {
    --body-bg: #f1f5f9;
    --widget-title-color: #1e293b;
    --exam-paper-bg: #ffffff;
    --exam-text-color: #334155;
    --exam-bold-color: #0f172a;
    --exam-title-color: #1e293b;
    --accent-cyan: #009eb3;
    --accent-gold: #b38600;

    /* Workspace Canvas Tokens in Light Mode */
    --el-bg: #e2e8f0;
    --el-sheet-bg: #ffffff;
    --el-sheet-border: #cbd5e1;
    --el-sheet-shadow: 0 12px 36px rgba(0, 0, 0, 0.08);
    --el-ribbon-bg: #ffffff;
    --el-ribbon-border: #cbd5e1;
    --el-palette-bg: #ffffff;
    --el-palette-border: #cbd5e1;
    --el-btn-hover: rgba(0, 158, 179, 0.1);
    --el-btn-active: rgba(0, 158, 179, 0.2);
    --el-dot-color: rgba(0, 158, 179, 0.25);
    --el-grid-color: rgba(0, 0, 0, 0.06);

    /* Block Tokens in Light Mode */
    --el-block-bg: rgba(0, 0, 0, 0.015);
    --el-block-border: transparent;
    --el-block-hover-border: rgba(0, 158, 179, 0.4);
    --el-block-selected-border: #009eb3;
    --el-block-selected-shadow: 0 0 14px rgba(0, 158, 179, 0.25);

    /* Bubble & Popover in Light Mode */
    --el-popover-bg: #1e293b;
    --el-popover-border: #475569;
    --el-popover-text: #f8fafc;
}

body {
    background-color: var(--body-bg);
    transition: background-color 0.3s ease;
}

/* Master Wrapper */
.main-wrapper {
    max-width: 100% !important;
    width: 100% !important;
    margin: 0 auto !important;
    padding: 0 16px;
    box-sizing: border-box;
}

.main-content-layout {
    display: block !important;
    margin-top: 10px;
    width: 100%;
}

.main-articles-body {
    width: 100%;
    min-width: 0;
}

/* Breadcrumb Bar */
.top-nav-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 8px;
}

.exam-back-btn {
    display: inline-flex; align-items: center; gap: 6px;
    color: var(--accent-cyan, #5ce1e6); text-decoration: none;
    font-size: 0.75rem; font-family: 'JetBrains Mono', monospace;
    letter-spacing: 0.6px; text-transform: uppercase;
    opacity: 0.8; transition: opacity 0.2s;
}
.exam-back-btn:hover { opacity: 1; }

.app-title-tag {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.78rem;
    color: var(--accent-cyan);
    font-weight: 600;
    letter-spacing: 0.5px;
    display: flex;
    align-items: center;
    gap: 6px;
}

/* ============================================================
   1. TOP RIBBON TOOLBAR (Mathcha Horizontal Formatting Bar)
   ============================================================ */
.mathcha-top-ribbon {
    background: var(--el-ribbon-bg);
    border: 1px solid var(--el-ribbon-border);
    border-radius: 8px;
    padding: 4px 10px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    margin-bottom: 12px;
    flex-wrap: nowrap;
    overflow-x: auto;
}

.ribbon-section {
    display: inline-flex;
    align-items: center;
    gap: 3px;
    white-space: nowrap;
}

.ribbon-divider {
    width: 1px;
    height: 20px;
    background: var(--el-ribbon-border);
    margin: 0 5px;
    opacity: 0.8;
}

/* Mode Switch Tabs in Ribbon */
.mode-tabs {
    display: inline-flex;
    background: rgba(92, 225, 230, 0.08);
    border: 1px solid rgba(92, 225, 230, 0.2);
    border-radius: 6px;
    padding: 2px;
}

.mode-tab-btn {
    background: transparent;
    border: none;
    color: var(--exam-text-color);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    padding: 3px 9px;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.15s;
    opacity: 0.75;
}

.mode-tab-btn:hover { opacity: 1; color: var(--accent-cyan); }
.mode-tab-btn.active {
    background: var(--accent-cyan);
    color: #0b1111 !important;
    font-weight: 700;
    opacity: 1;
}

/* Ribbon Icon Buttons (Mathcha Style: B, I, U, S, Align, Undo) */
.rb-btn {
    background: transparent;
    border: 1px solid transparent;
    border-radius: 4px;
    color: var(--exam-text-color);
    padding: 4px 6px;
    height: 28px;
    min-width: 28px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 0.88rem;
    font-family: 'JetBrains Mono', monospace;
    transition: all 0.15s;
    user-select: none;
}

.rb-btn:hover {
    background: var(--el-btn-hover);
    color: var(--accent-cyan);
    border-color: rgba(92, 225, 230, 0.3);
}

.rb-btn.active {
    background: var(--el-btn-active);
    color: var(--accent-cyan);
    border-color: var(--accent-cyan);
}

.rb-select {
    background: transparent;
    border: 1px solid rgba(92, 225, 230, 0.2);
    border-radius: 4px;
    color: var(--exam-text-color);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    padding: 3px 6px;
    outline: none;
    cursor: pointer;
    height: 28px;
}

/* Color Tool with Underbar */
.color-tool-wrap {
    position: relative;
    display: inline-flex;
    align-items: center;
}

.color-indicator-btn {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 28px;
    width: 28px;
    background: transparent;
    border: 1px solid transparent;
    border-radius: 4px;
    cursor: pointer;
    color: var(--exam-text-color);
}

.color-indicator-btn:hover {
    background: var(--el-btn-hover);
}

.color-bar {
    width: 14px;
    height: 3px;
    border-radius: 1px;
    background: var(--accent-cyan);
    margin-top: 1px;
}

/* Export CTA Button */
.export-cta-btn {
    background: var(--accent-cyan) !important;
    color: #0b1111 !important;
    font-weight: 700;
    border-radius: 5px;
    padding: 4px 12px;
    font-size: 0.74rem;
    letter-spacing: 0.4px;
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 5px;
    transition: filter 0.2s, transform 0.15s;
}

.export-cta-btn:hover {
    filter: brightness(1.1);
    transform: translateY(-1px);
}

/* ============================================================
   2. MAIN WORKSPACE WITH LEFT PALETTE & CENTER SHEET
   ============================================================ */
.mathcha-workspace-layout {
    position: relative;
    width: 100%;
    display: flex;
    gap: 12px;
    align-items: flex-start;
}

/* Left Floating Tool Palette (Mathcha Vertical Tool Strip) */
.mathcha-left-palette {
    position: sticky;
    top: 20px;
    background: var(--el-palette-bg);
    border: 1px solid var(--el-palette-border);
    border-radius: 8px;
    padding: 6px 4px;
    display: flex;
    flex-direction: column;
    gap: 6px;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.25);
    z-index: 10;
}

.palette-btn {
    background: transparent;
    border: 1px solid transparent;
    border-radius: 6px;
    color: var(--exam-text-color);
    width: 34px;
    height: 34px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.1rem;
    transition: all 0.15s;
    position: relative;
}

.palette-btn:hover {
    background: var(--el-btn-hover);
    color: var(--accent-cyan);
    border-color: rgba(92, 225, 230, 0.35);
    transform: scale(1.08);
}

.palette-btn.btn-active {
    background: var(--el-btn-active);
    color: var(--accent-cyan);
    border-color: var(--accent-cyan);
}

.palette-btn.del:hover {
    color: #ef4444;
    background: rgba(239, 68, 68, 0.15);
    border-color: #ef4444;
}

/* Tooltip on palette buttons */
.palette-btn[data-tip]:hover:after {
    content: attr(data-tip);
    position: absolute;
    left: 42px;
    top: 50%;
    transform: translateY(-50%);
    background: var(--el-popover-bg);
    color: #fff;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.72rem;
    padding: 3px 8px;
    border-radius: 4px;
    white-space: nowrap;
    border: 1px solid var(--el-popover-border);
    pointer-events: none;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
    z-index: 1000;
}

/* Canvas Viewport (Center Stage - Cuộn mượt mà như cũ, hỗ trợ nhiều trang) */
.mathcha-canvas-viewport {
    flex: 1;
    position: relative;
    height: calc(100vh - 180px);
    min-height: 600px;
    background-color: var(--el-bg);
    border: 1px solid var(--el-ribbon-border);
    border-radius: 10px;
    overflow-y: auto;
    overflow-x: auto;
    cursor: default;
    user-select: none;
    box-sizing: border-box;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    padding: 24px 20px 60px;
}

.mathcha-canvas-viewport.grid-dots {
    background-image: radial-gradient(var(--el-dot-color) 1px, transparent 1px);
    background-size: 20px 20px;
}

.mathcha-canvas-viewport.grid-lines {
    background-image: 
        linear-gradient(to right, var(--el-grid-color) 1px, transparent 1px),
        linear-gradient(to bottom, var(--el-grid-color) 1px, transparent 1px);
    background-size: 20px 20px;
}

.mathcha-canvas-viewport.grid-none {
    background-image: none;
}

/* Page Navigation Strip (Thanh Điều Hướng & Quản Lý Trang) */
.mathcha-page-strip {
    display: flex;
    align-items: center;
    gap: 8px;
    background: var(--el-ribbon-bg);
    border: 1px solid var(--el-ribbon-border);
    border-radius: 8px;
    padding: 6px 14px;
    margin-bottom: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
    flex-wrap: wrap;
}

.page-nav-controls {
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.page-indicator {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--el-text);
    padding: 2px 8px;
    font-family: 'JetBrains Mono', monospace;
}

.page-tabs-container {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    overflow-x: auto;
    max-width: 50vw;
}

.page-tab-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 12px;
    border-radius: 6px;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.08);
    color: var(--el-text-muted);
    cursor: pointer;
    font-size: 0.8rem;
    font-weight: 500;
    transition: all 0.15s ease;
    white-space: nowrap;
}

.page-tab-item:hover {
    color: var(--el-text);
    border-color: var(--accent-cyan);
    background: rgba(92, 225, 230, 0.08);
}

.page-tab-item.active {
    color: var(--accent-cyan);
    border-color: var(--accent-cyan);
    background: rgba(92, 225, 230, 0.16);
    font-weight: 700;
    box-shadow: 0 0 10px rgba(92, 225, 230, 0.2);
}

.page-add-btn, .page-nav-btn {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 4px 10px;
    border-radius: 6px;
    background: rgba(92, 225, 230, 0.1);
    border: 1px solid rgba(92, 225, 230, 0.3);
    color: var(--accent-cyan);
    font-size: 0.78rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
    white-space: nowrap;
}

.page-add-btn:hover, .page-nav-btn:hover {
    background: rgba(92, 225, 230, 0.22);
    border-color: var(--accent-cyan);
    transform: translateY(-1px);
}

.page-del-btn {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 4px 10px;
    border-radius: 6px;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #f87171;
    font-size: 0.76rem;
    cursor: pointer;
    transition: all 0.15s ease;
    margin-left: auto;
}

.page-del-btn:hover {
    background: rgba(239, 68, 68, 0.22);
    border-color: #ef4444;
}

.page-bottom-add-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-top: 14px;
    margin-bottom: 24px;
    padding: 10px 28px;
    border-radius: 24px;
    background: rgba(92, 225, 230, 0.06);
    border: 1.5px dashed rgba(92, 225, 230, 0.45);
    color: var(--accent-cyan);
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    flex-shrink: 0;
}

.page-bottom-add-btn:hover {
    background: rgba(92, 225, 230, 0.16);
    border-color: var(--accent-cyan);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(92, 225, 230, 0.25);
}

/* Artboard Sheet Container */
.artboard {
    position: relative;
    transition: width 0.25s cubic-bezier(0.4, 0, 0.2, 1), height 0.25s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.2s;
    box-sizing: border-box;
}

/* 1. Bảng Vẽ (Drawing Box Frame) */
.artboard.mode-canvas {
    width: 960px;
    max-width: 95%;
    min-height: 560px;
    background: var(--el-sheet-bg);
    border: 2px dashed var(--accent-cyan);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
    border-radius: 10px;
    margin: 0 auto 24px;
    flex-shrink: 0;
}

/* 2. Khổ Giấy A4 (Chuẩn Tờ Giấy Tự Nhiên Như Cũ) */
.artboard.mode-a4 {
    width: 820px;
    max-width: 95%;
    min-height: 1140px;
    background: var(--el-sheet-bg);
    border: 1px solid var(--el-sheet-border);
    box-shadow: var(--el-sheet-shadow);
    border-radius: 6px;
    margin: 0 auto 24px;
    flex-shrink: 0;
}

/* 3. Slide Beamer (16:9 Presentation Frame) */
.artboard.mode-beamer {
    width: 960px;
    max-width: 95%;
    height: 540px;
    min-height: 540px;
    background: var(--el-sheet-bg);
    border: 2px solid var(--accent-cyan);
    box-shadow: var(--el-sheet-shadow);
    border-radius: 8px;
    margin: 0 auto 24px;
    flex-shrink: 0;
}

.sheet-badge {
    position: absolute;
    top: 8px;
    right: 12px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.65rem;
    color: var(--accent-cyan);
    opacity: 0.45;
    pointer-events: none;
    letter-spacing: 0.5px;
    text-transform: uppercase;
}

.canvas-empty-hint {
    position: absolute;
    top: 45%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: var(--exam-text-color);
    opacity: 0.4;
    pointer-events: none;
    font-size: 0.88rem;
    font-family: 'JetBrains Mono', monospace;
    line-height: 1.6;
}

/* ============================================================
   3. MOVABLE BLOCKS (Minimalist, No Clunky Headers)
   ============================================================ */
.movable-block {
    position: absolute;
    background: var(--el-block-bg);
    border: 1px solid var(--el-block-border);
    border-radius: 6px;
    min-width: 90px;
    min-height: 42px;
    display: flex;
    flex-direction: column;
    user-select: text;
    transition: box-shadow 0.15s, border-color 0.15s;
    touch-action: none;
}

.movable-block:hover {
    border-color: var(--el-block-hover-border);
}

.movable-block.selected {
    border-color: var(--el-block-selected-border) !important;
    box-shadow: var(--el-block-selected-shadow);
    z-index: 50 !important;
}

/* Floating Action Bar on top of block (Rõ ràng, dễ nhìn, dễ bấm) */
.block-handle-bar {
    position: absolute;
    top: -36px;
    left: 0;
    height: 30px;
    background: #182234;
    border: 1.5px solid var(--accent-cyan);
    border-radius: 6px;
    display: none;
    align-items: center;
    gap: 6px;
    padding: 0 8px;
    cursor: default;
    user-select: none;
    z-index: 60;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.55), 0 0 10px rgba(92, 225, 230, 0.2);
    animation: fadeInBar 0.15s ease-out;
    white-space: nowrap;
}

@keyframes fadeInBar {
    from { opacity: 0; transform: translateY(4px); }
    to { opacity: 1; transform: translateY(0); }
}

.movable-block:hover .block-handle-bar,
.movable-block.selected .block-handle-bar {
    display: flex;
}

.block-handle-drag {
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--accent-cyan);
    cursor: grab;
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding-right: 6px;
    border-right: 1px solid rgba(255, 255, 255, 0.15);
}

.block-handle-drag:active {
    cursor: grabbing;
}

.block-bar-btn {
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: #e2e8f0;
    cursor: pointer;
    font-size: 0.76rem;
    font-weight: 500;
    padding: 3px 8px;
    border-radius: 4px;
    display: inline-flex;
    align-items: center;
    gap: 4px;
    line-height: 1.2;
    transition: all 0.15s ease;
}

.block-bar-btn:hover {
    background: rgba(255, 255, 255, 0.15);
    color: #ffffff;
    border-color: rgba(255, 255, 255, 0.3);
}

.block-bar-btn.btn-suggest-pill {
    background: rgba(92, 225, 230, 0.18);
    border: 1px solid var(--accent-cyan);
    color: var(--accent-cyan);
    font-weight: 700;
    font-size: 0.78rem;
}

.block-bar-btn.btn-suggest-pill:hover {
    background: var(--accent-cyan);
    color: #0b1120;
    box-shadow: 0 0 10px rgba(92, 225, 230, 0.4);
}

.block-bar-btn.btn-del {
    color: #f87171;
    border-color: rgba(239, 68, 68, 0.3);
}

.block-bar-btn.btn-del:hover {
    background: #ef4444;
    color: #ffffff;
    border-color: #ef4444;
}

.block-body {
    padding: 4px 8px;
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

math-field {
    border: none !important;
    outline: none !important;
    font-size: 1.35rem;
    color: var(--exam-text-color);
    background: transparent !important;
    width: 100%;
    min-height: 32px;
    padding: 2px;
    --caret-color: var(--accent-cyan);
    --selection-background-color: rgba(92,225,230,0.2);
    --selection-color: var(--accent-cyan);
}

.text-editor-area {
    outline: none;
    min-height: 24px;
    font-size: 0.95rem;
    line-height: 1.5;
    color: var(--exam-text-color);
    word-break: break-word;
}

.text-editor-area:empty:before {
    content: attr(placeholder);
    color: var(--exam-text-color);
    opacity: 0.35;
    pointer-events: none;
}

.movable-block.block-box {
    border: 2px dashed var(--accent-gold);
    background: rgba(201, 169, 110, 0.05);
}

.resize-handle {
    position: absolute;
    right: 2px;
    bottom: 2px;
    width: 10px;
    height: 10px;
    cursor: se-resize;
    opacity: 0;
    transition: opacity 0.2s;
    background: linear-gradient(135deg, transparent 50%, var(--accent-cyan) 50%);
    border-radius: 0 0 3px 0;
}

.movable-block:hover .resize-handle,
.movable-block.selected .resize-handle {
    opacity: 0.8;
}

/* ============================================================
   4. FLOATING SELECTION BUBBLE (On Highlight Text)
   ============================================================ */
.floating-bubble-toolbar {
    position: fixed;
    z-index: 99999;
    background: var(--el-popover-bg);
    border: 1px solid var(--el-popover-border);
    border-radius: 6px;
    padding: 3px 6px;
    display: none;
    align-items: center;
    gap: 4px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    transform: translateX(-50%);
    animation: bubbleFadeIn 0.15s ease-out;
}

.floating-bubble-toolbar.active {
    display: flex;
}

@keyframes bubbleFadeIn {
    from { opacity: 0; transform: translate(-50%, 6px); }
    to { opacity: 1; transform: translate(-50%, 0); }
}

.bubble-btn {
    background: transparent;
    border: none;
    color: var(--el-popover-text);
    padding: 4px 6px;
    border-radius: 3px;
    cursor: pointer;
    font-size: 0.82rem;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s, color 0.15s;
    height: 24px;
    min-width: 24px;
}

.bubble-btn:hover {
    background: var(--el-btn-hover);
    color: var(--accent-cyan);
}

.bubble-divider {
    width: 1px;
    height: 16px;
    background: rgba(255, 255, 255, 0.15);
    margin: 0 2px;
}

.bubble-color-picker {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 0 2px;
}

.color-dot {
    width: 13px;
    height: 13px;
    border-radius: 50%;
    cursor: pointer;
    border: 1px solid rgba(255, 255, 255, 0.3);
    transition: transform 0.15s;
}

.color-dot:hover {
    transform: scale(1.3);
}

/* ============================================================
   5. SLIDE-UP EXPORT DRAWER (Modern Bottom Sheet)
   ============================================================ */
.export-drawer-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 100000;
    display: none;
    align-items: flex-end;
    justify-content: center;
}

.export-drawer-overlay.active {
    display: flex;
}

.export-drawer-sheet {
    background: var(--el-sheet-bg);
    border: 1px solid var(--el-sheet-border);
    border-radius: 14px 14px 0 0;
    width: 100%;
    max-width: 980px;
    max-height: 85vh;
    display: flex;
    flex-direction: column;
    box-shadow: 0 -10px 40px rgba(0, 0, 0, 0.6);
    animation: drawerUp 0.25s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes drawerUp {
    from { transform: translateY(100%); }
    to { transform: translateY(0); }
}

.drawer-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 18px;
    border-bottom: 1px solid var(--el-ribbon-border);
}

.drawer-title {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.88rem;
    font-weight: 600;
    color: var(--accent-cyan);
    display: flex;
    align-items: center;
    gap: 8px;
}

.drawer-close-btn {
    background: transparent;
    border: none;
    color: var(--exam-text-color);
    font-size: 1.3rem;
    cursor: pointer;
    line-height: 1;
    opacity: 0.6;
}
.drawer-close-btn:hover { opacity: 1; color: var(--accent-cyan); }

.drawer-body {
    padding: 16px 18px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    overflow-y: auto;
}

.drawer-action-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 8px;
}

.drawer-action-btn {
    background: rgba(92, 225, 230, 0.1);
    border: 1px solid rgba(92, 225, 230, 0.25);
    border-radius: 5px;
    padding: 6px 12px;
    color: var(--accent-cyan);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.74rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s;
}

.drawer-action-btn:hover {
    background: rgba(92, 225, 230, 0.22);
    border-color: var(--accent-cyan);
}

.drawer-action-btn.btn-primary {
    background: var(--accent-cyan);
    color: #0b1111;
}

#latex-output {
    width: 100%;
    height: 240px;
    background: rgba(0, 0, 0, 0.25);
    border: 1px solid var(--el-ribbon-border);
    border-radius: 8px;
    padding: 12px;
    color: var(--exam-text-color);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.84rem;
    line-height: 1.5;
    resize: vertical;
    outline: none;
    box-sizing: border-box;
}

body:not(.dark-mode) #latex-output {
    background: #f8fafc;
}

/* Toast */
.el-toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(20px);
    background: #0f172a;
    color: #fff;
    padding: 8px 18px;
    border-radius: 6px;
    font-size: 0.80rem;
    font-family: 'JetBrains Mono', monospace;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    opacity: 0;
    pointer-events: none;
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 1000000;
    display: flex;
    align-items: center;
    gap: 8px;
    border-left: 3px solid var(--accent-cyan);
}

.el-toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* Zen Mode */
body.zen-mode #sidebar-placeholder,
body.zen-mode #topbar-placeholder,
body.zen-mode .top-nav-bar {
    display: none !important;
}

body.zen-mode .mathcha-canvas-viewport {
    height: calc(100vh - 80px) !important;
}

/* ============================================================
   6. LATEX AUTOCOMPLETE SUGGESTION POPUP (Mathcha Style List)
   ============================================================ */
.latex-suggest-popup {
    position: fixed;
    z-index: 999999;
    background: #141c2e;
    border: 1.5px solid var(--accent-cyan);
    border-radius: 10px;
    box-shadow: 0 16px 45px rgba(0, 0, 0, 0.75), 0 0 20px rgba(92, 225, 230, 0.25);
    display: none;
    flex-direction: column;
    width: 360px;
    max-width: 95vw;
    backdrop-filter: blur(16px);
    overflow: hidden;
    animation: popupSlideDown 0.15s ease-out;
}

@keyframes popupSlideDown {
    from { opacity: 0; transform: translateY(-6px); }
    to { opacity: 1; transform: translateY(0); }
}

.latex-suggest-popup.active {
    display: flex;
}

.suggest-search-bar {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    background: rgba(0, 0, 0, 0.4);
    border-bottom: 1px solid rgba(92, 225, 230, 0.25);
}

.suggest-search-icon {
    font-size: 0.9rem;
    opacity: 0.8;
}

.suggest-search-input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    color: #ffffff;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.84rem;
}

.suggest-search-input::placeholder {
    color: #64748b;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    font-size: 0.78rem;
}

.suggest-close-btn {
    background: transparent;
    border: none;
    color: #94a3b8;
    cursor: pointer;
    font-size: 0.85rem;
    padding: 2px 6px;
    border-radius: 4px;
    transition: all 0.15s;
}

.suggest-close-btn:hover {
    color: #ef4444;
    background: rgba(239, 68, 68, 0.15);
}

.suggest-list-container {
    overflow-y: auto;
    max-height: 280px;
    padding: 6px;
    display: flex;
    flex-direction: column;
    gap: 3px;
}

.suggest-list-container::-webkit-scrollbar {
    width: 5px;
}
.suggest-list-container::-webkit-scrollbar-thumb {
    background: rgba(92, 225, 230, 0.3);
    border-radius: 4px;
}

.suggest-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 7px 10px;
    border-radius: 6px;
    cursor: pointer;
    color: #cbd5e1;
    border: 1px solid transparent;
    transition: all 0.12s ease;
    user-select: none;
}

.suggest-item:hover,
.suggest-item.highlighted {
    background: rgba(92, 225, 230, 0.18);
    border-color: var(--accent-cyan);
    color: #ffffff !important;
    transform: translateX(2px);
}

.suggest-item-left {
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 0;
}

.suggest-badge-preview {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 32px;
    height: 28px;
    padding: 0 6px;
    border-radius: 4px;
    background: rgba(92, 225, 230, 0.12);
    color: var(--accent-cyan);
    font-weight: 700;
    font-size: 0.95rem;
    font-family: 'JetBrains Mono', serif;
    flex-shrink: 0;
}

.suggest-item.highlighted .suggest-badge-preview {
    background: var(--accent-cyan);
    color: #0b1120;
}

.suggest-item-text {
    display: flex;
    flex-direction: column;
    min-width: 0;
}

.suggest-cmd-name {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.82rem;
    font-weight: 600;
    color: #f8fafc;
}

.suggest-tag-desc {
    font-size: 0.72rem;
    color: #94a3b8;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.suggest-enter-hint {
    font-size: 0.7rem;
    color: var(--accent-cyan);
    opacity: 0;
    transition: opacity 0.15s;
    font-weight: 600;
    flex-shrink: 0;
}

.suggest-item.highlighted .suggest-enter-hint {
    opacity: 1;
}

.suggest-footer-hint {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 6px 12px;
    background: rgba(0, 0, 0, 0.45);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    font-size: 0.72rem;
    color: #64748b;
}

.suggest-footer-hint b {
    color: var(--accent-cyan);
}