/* physics-viewer.css - NEON BLUE THEME WITH MOBILE HAMBURGER MENU */

.physics-viewer-container {
    display: flex;
    height: calc(100vh - 80px);
    background: linear-gradient(135deg, #0a0f1a 0%, #0a1525 100%);
    color: #e0e0ff;
    position: relative;
    overflow: hidden;
}

/* ========== SIDEBAR - DESKTOP STYLE ========== */
.viewer-sidebar {
    width: 320px;
    background: linear-gradient(135deg, rgba(10, 25, 47, 0.98), rgba(5, 15, 30, 0.98));
    border-right: 2px solid rgba(0, 255, 255, 0.3);
    display: flex;
    flex-direction: column;
    transition: width 0.3s ease;
    position: relative;
    z-index: 10;
    backdrop-filter: blur(10px);
    box-shadow: 5px 0 30px rgba(0, 0, 0, 0.5);
}

.viewer-sidebar.collapsed {
    width: 70px;
}

.viewer-sidebar.collapsed .sidebar-header h3,
.viewer-sidebar.collapsed .chapter-item .chapter-title,
.viewer-sidebar.collapsed .back-to-course span:last-child {
    display: none;
}

.viewer-sidebar.collapsed .chapter-number {
    margin: 0 auto;
}

.viewer-sidebar.collapsed .back-to-course {
    justify-content: center;
}

.sidebar-header {
    padding: 1.5rem 1rem;
    border-bottom: 1px solid rgba(0, 255, 255, 0.2);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.sidebar-header h3 {
    color: #00ffff;
    margin: 0;
    font-size: 1.2rem;
    text-shadow: 0 0 10px rgba(0, 255, 255, 0.3);
}

.sidebar-toggle {
    background: transparent;
    border: 1px solid #00ffff;
    color: #00ffff;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    font-size: 1rem;
}

.sidebar-toggle:hover {
    background: rgba(0, 255, 255, 0.2);
    transform: scale(1.1);
    box-shadow: 0 0 15px rgba(0, 255, 255, 0.5);
}

/* Chapter List */
.chapter-list {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
}

.chapter-list::-webkit-scrollbar {
    width: 6px;
}

.chapter-list::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
}

.chapter-list::-webkit-scrollbar-thumb {
    background: rgba(0, 255, 255, 0.3);
    border-radius: 3px;
}

.chapter-list::-webkit-scrollbar-thumb:hover {
    background: rgba(0, 255, 255, 0.5);
}

.chapter-item {
    padding: 1rem;
    margin-bottom: 0.5rem;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(0, 255, 255, 0.15);
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 12px;
}

.chapter-item:hover {
    background: rgba(0, 255, 255, 0.1);
    border-color: #00ffff;
    transform: translateX(5px);
    box-shadow: 0 4px 15px rgba(0, 255, 255, 0.2);
}

.chapter-item.active {
    background: linear-gradient(45deg, rgba(0, 255, 255, 0.2), rgba(0, 153, 255, 0.2));
    border-color: #00ffff;
    border-left-width: 4px;
    box-shadow: 0 4px 20px rgba(0, 255, 255, 0.3);
}

.chapter-number {
    background: #00ffff;
    color: #0a0a1a;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: bold;
    flex-shrink: 0;
    box-shadow: 0 0 10px rgba(0, 255, 255, 0.5);
}

.chapter-title {
    flex: 1;
    font-size: 0.95rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    color: #e0e0ff;
}

.sidebar-footer {
    padding: 1rem;
    border-top: 1px solid rgba(0, 255, 255, 0.2);
}

.back-to-course {
    display: flex;
    align-items: center;
    gap: 8px;
    color: #00ffff;
    text-decoration: none;
    padding: 0.75rem;
    border-radius: 8px;
    transition: all 0.3s ease;
}

.back-to-course:hover {
    background: rgba(0, 255, 255, 0.1);
}

/* ========== MAIN DOCUMENT AREA ========== */
.document-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: linear-gradient(135deg, #0f1a2a 0%, #0a1525 100%);
}

/* Toolbar */
.document-toolbar {
    padding: 1rem 2rem;
    background: rgba(10, 25, 47, 0.95);
    border-bottom: 2px solid rgba(0, 255, 255, 0.2);
    display: flex;
    justify-content: space-between;
    align-items: center;
    backdrop-filter: blur(10px);
    min-height: 60px;
}

.chapter-title-display {
    color: #00ffff;
    font-size: 1.4rem;
    font-weight: 600;
    text-shadow: 0 0 10px rgba(0, 255, 255, 0.3);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 70%;
}

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

.tool-btn {
    background: transparent;
    border: 1px solid rgba(0, 255, 255, 0.3);
    color: #00ffff;
    width: 40px;
    height: 40px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.2rem;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.tool-btn:hover {
    background: rgba(0, 255, 255, 0.1);
    border-color: #00ffff;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 255, 255, 0.3);
}

/* Document Content Area */
.document-content {
    flex: 1;
    overflow-y: auto;
    padding: 2rem;
    line-height: 1.8;
    font-size: 1.1rem;
    scroll-behavior: smooth;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
    box-sizing: border-box;
}

.document-content > *:first-child {
    margin-top: 0;
}

.document-content > *:last-child {
    margin-bottom: 0;
}

.document-content::-webkit-scrollbar {
    width: 8px;
}

.document-content::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
}

.document-content::-webkit-scrollbar-thumb {
    background: rgba(0, 255, 255, 0.3);
    border-radius: 4px;
}

.document-content::-webkit-scrollbar-thumb:hover {
    background: rgba(0, 255, 255, 0.5);
}

/* Document content styling */
.document-content h1 {
    color: #00ffff;
    font-size: 2.5rem;
    margin: 0 0 1.5rem 0;
    border-bottom: 2px solid rgba(0, 255, 255, 0.3);
    padding-bottom: 0.75rem;
    line-height: 1.2;
}

.document-content h2 {
    color: #00bfff;
    font-size: 2rem;
    margin: 2rem 0 1rem 0;
    line-height: 1.3;
}

.document-content h3 {
    color: #88ddff;
    font-size: 1.5rem;
    margin: 1.5rem 0 0.75rem 0;
    line-height: 1.4;
}

.document-content p {
    margin: 0 0 1.2rem 0;
    color: #e0e0ff;
    line-height: 1.8;
}

.document-content ul, 
.document-content ol {
    margin: 1rem 0 1.5rem 0;
    padding-left: 2rem;
}

.document-content li {
    margin-bottom: 0.5rem;
    color: #d0d0ff;
    line-height: 1.7;
}

.document-content code {
    background: rgba(0, 255, 255, 0.1);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    color: #00ffff;
    font-family: 'Courier New', monospace;
}

.document-content pre {
    background: rgba(0, 0, 0, 0.3);
    padding: 1.2rem;
    border-radius: 8px;
    border: 1px solid rgba(0, 255, 255, 0.2);
    overflow-x: auto;
    margin: 1.5rem 0;
}

.document-content img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    border: 1px solid rgba(0, 255, 255, 0.2);
    margin: 1.5rem 0;
    display: block;
}

.document-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
    background: rgba(255, 255, 255, 0.02);
    border-radius: 8px;
    overflow: hidden;
}

.document-content th {
    background: rgba(0, 255, 255, 0.1);
    color: #00ffff;
    font-weight: 600;
    padding: 0.75rem 1rem;
    text-align: left;
}

.document-content td {
    padding: 0.75rem 1rem;
    border-bottom: 1px solid rgba(0, 255, 255, 0.1);
    color: #d0d0ff;
}

/* Physics equation styling */
.physics-equation {
    background: rgba(0, 191, 255, 0.15);
    padding: 1.5rem;
    border-radius: 12px;
    border-left: 6px solid #00ffff;
    margin: 2rem 0;
    font-family: 'Courier New', monospace;
    font-size: 1.2rem;
    box-shadow: 0 4px 20px rgba(0, 255, 255, 0.1);
    overflow-x: auto;
    text-align: center;
}

.diagram-container {
    background: rgba(0, 255, 255, 0.05);
    padding: 2rem;
    border-radius: 15px;
    border: 1px solid rgba(0, 255, 255, 0.3);
    margin: 2rem 0;
    text-align: center;
}

/* Loading states */
.loading-spinner {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 300px;
    color: #00ffff;
    font-size: 1.2rem;
    gap: 15px;
}

.loading-spinner::after {
    content: '';
    width: 30px;
    height: 30px;
    border: 3px solid rgba(0, 255, 255, 0.3);
    border-top-color: #00ffff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.error-message {
    text-align: center;
    padding: 4rem 2rem;
    color: #ff6b6b;
}

.error-message h3 {
    color: #ff6b6b;
    font-size: 2rem;
    margin-bottom: 1rem;
}

.retry-btn {
    background: linear-gradient(45deg, #00ffff, #0099ff);
    color: #0a0a1a;
    border: none;
    padding: 1rem 2rem;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: bold;
    cursor: pointer;
    margin: 2rem 0;
    transition: all 0.3s ease;
}

.retry-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 255, 255, 0.4);
}

/* Navigation between chapters */
.document-navigation {
    padding: 1rem 2rem;
    background: rgba(10, 25, 47, 0.95);
    border-top: 2px solid rgba(0, 255, 255, 0.2);
    display: flex;
    justify-content: space-between;
    gap: 1rem;
}

.nav-btn {
    background: linear-gradient(45deg, rgba(0, 255, 255, 0.1), rgba(0, 153, 255, 0.1));
    border: 1px solid rgba(0, 255, 255, 0.3);
    color: #00ffff;
    padding: 0.75rem 2rem;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: bold;
    transition: all 0.3s ease;
    flex: 1;
    max-width: 200px;
}

.nav-btn:hover:not(:disabled) {
    background: linear-gradient(45deg, rgba(0, 255, 255, 0.2), rgba(0, 153, 255, 0.2));
    border-color: #00ffff;
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0, 255, 255, 0.3);
}

.nav-btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

/* File download section */
.document-file-section {
    margin: 3rem 0 2rem 0;
    padding: 2rem;
    background: rgba(0, 255, 255, 0.05);
    border-radius: 15px;
    border: 1px solid rgba(0, 255, 255, 0.3);
}

.document-file-info {
    display: flex;
    align-items: center;
    gap: 2rem;
    padding: 1.5rem;
    background: rgba(255, 255, 255, 0.02);
    border-radius: 12px;
    flex-wrap: wrap;
}

.file-icon-large {
    font-size: 3rem;
    color: #00ffff;
}

.file-details {
    flex: 1;
}

.file-details h4 {
    color: #00ffff;
    margin: 0 0 0.5rem 0;
    font-size: 1.2rem;
}

.file-meta {
    color: #a0a0c0;
    font-size: 0.9rem;
}

.download-btn-large {
    background: linear-gradient(45deg, #00ffff, #0099ff);
    color: #0a0a1a;
    border: none;
    padding: 0.75rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: bold;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.download-btn-large:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 255, 255, 0.4);
}

/* Questions section */
.document-questions {
    margin: 3rem 0 1rem 0;
    padding: 2rem;
    background: rgba(0, 191, 255, 0.05);
    border-radius: 15px;
}

.document-questions h3 {
    color: #00bfff;
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
}

.document-questions ul {
    list-style: none;
    padding: 0;
}

.document-questions li {
    background: rgba(255, 255, 255, 0.02);
    margin: 1rem 0;
    padding: 1.2rem 1.5rem;
    border-radius: 10px;
    border-left: 4px solid #00bfff;
    transition: all 0.3s ease;
    color: #d0d0ff;
}

.document-questions li:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateX(5px);
}

/* ========== MOBILE STYLES - HAMBURGER MENU ========== */
@media (max-width: 768px) {
    .physics-viewer-container {
        flex-direction: column;
        height: calc(100vh - 60px);
        position: relative;
    }
    
    /* Sidebar becomes a slide-out menu */
    .viewer-sidebar {
        position: fixed;
        top: 60px;
        left: -320px;
        width: 280px;
        height: calc(100vh - 60px);
        z-index: 1000;
        transition: left 0.3s ease;
        border-right: 2px solid rgba(0, 255, 255, 0.3);
        box-shadow: 5px 0 30px rgba(0, 0, 0, 0.8);
    }
    
    .viewer-sidebar.mobile-open {
        left: 0;
    }
    
    .viewer-sidebar.collapsed {
        width: 280px;
        left: -280px;
    }
    
    .viewer-sidebar.collapsed.mobile-open {
        left: 0;
    }
    
    .viewer-sidebar.collapsed .sidebar-header h3,
    .viewer-sidebar.collapsed .chapter-item .chapter-title,
    .viewer-sidebar.collapsed .back-to-course span:last-child {
        display: block;
    }
    
    .viewer-sidebar.collapsed .chapter-number {
        margin: 0;
    }
    
    .viewer-sidebar.collapsed .back-to-course {
        justify-content: flex-start;
    }
    
    /* Overlay when sidebar is open */
    .sidebar-overlay {
        display: none;
        position: fixed;
        top: 60px;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0, 0, 0, 0.7);
        z-index: 999;
        backdrop-filter: blur(3px);
    }
    
    .sidebar-overlay.active {
        display: block;
    }
    
    /* Hide the old sidebar toggle on mobile */
    .sidebar-toggle {
        display: none;
    }
    
    /* Add hamburger button to toolbar */
    .mobile-menu-btn {
        display: block !important;
        background: transparent;
        border: 1px solid #00ffff;
        color: #00ffff;
        width: 40px;
        height: 40px;
        border-radius: 8px;
        cursor: pointer;
        font-size: 1.5rem;
        margin-right: 10px;
        line-height: 1;
        flex-shrink: 0;
    }
    
    .document-toolbar {
        padding: 0.5rem 1rem;
        position: relative;
        display: flex;
        align-items: center;
    }
    
    .toolbar-left {
        display: flex;
        align-items: center;
        flex: 1;
        min-width: 0;
    }
    
    .chapter-title-display {
        font-size: 1.1rem;
        max-width: none;
        flex: 1;
        margin-left: 0;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
    }
    
    .toolbar-actions {
        gap: 0.25rem;
        flex-shrink: 0;
    }
    
    .tool-btn {
        width: 36px;
        height: 36px;
        font-size: 1rem;
    }
    
    .document-content {
        padding: 1.2rem;
        font-size: 1rem;
        line-height: 1.6;
        max-width: 100%;
        margin: 0;
    }
    
    .document-content h1 {
        font-size: 1.6rem;
        margin: 0 0 1rem 0;
    }
    
    .document-content h2 {
        font-size: 1.4rem;
        margin: 1.5rem 0 0.8rem 0;
    }
    
    .document-content h3 {
        font-size: 1.2rem;
        margin: 1.2rem 0 0.5rem 0;
    }
    
    .document-content p {
        font-size: 1rem;
        margin-bottom: 1rem;
        line-height: 1.6;
    }
    
    .document-content ul, 
    .document-content ol {
        padding-left: 1.2rem;
        margin: 0.8rem 0 1.2rem 0;
    }
    
    .document-content li {
        font-size: 1rem;
        margin-bottom: 0.4rem;
    }
    
    .physics-equation {
        padding: 1rem;
        font-size: 1rem;
        white-space: normal;
        word-break: break-word;
        overflow-x: auto;
    }
    
    .diagram-container {
        padding: 1rem;
    }
    
    .document-content table {
        display: block;
        overflow-x: auto;
        white-space: nowrap;
        font-size: 0.9rem;
    }
    
    .document-content pre {
        white-space: pre-wrap;
        word-wrap: break-word;
        padding: 0.8rem;
        font-size: 0.9rem;
    }
    
    .document-navigation {
        padding: 0.75rem 1rem;
        gap: 0.5rem;
    }
    
    .nav-btn {
        max-width: none;
        padding: 0.6rem 1rem;
        font-size: 0.9rem;
    }
    
    .document-file-section {
        margin: 2rem 0 1.5rem 0;
        padding: 1.2rem;
    }
    
    .document-file-info {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
        padding: 1rem;
    }
    
    .download-btn-large {
        width: 100%;
        justify-content: center;
    }
    
    .document-questions {
        margin: 2rem 0 1rem 0;
        padding: 1.2rem;
    }
    
    .document-questions li {
        padding: 1rem;
    }
}

/* Extra small devices */
@media (max-width: 480px) {
    .document-content {
        padding: 1rem;
    }
    
    .document-content h1 {
        font-size: 1.5rem;
    }
    
    .document-content h2 {
        font-size: 1.3rem;
    }
    
    .document-toolbar {
        flex-wrap: wrap;
    }
    
    .toolbar-left {
        width: 100%;
        margin-bottom: 0.3rem;
    }
    
    .toolbar-actions {
        width: 100%;
        justify-content: flex-end;
    }
    
    .document-navigation {
        flex-direction: column;
    }
    
    .nav-btn {
        width: 100%;
    }
    
    .physics-equation {
        font-size: 0.9rem;
    }
}

/* Desktop styles */
.mobile-menu-btn {
    display: none;
}

/* Print styles */
@media print {
    .viewer-sidebar,
    .document-toolbar,
    .document-navigation,
    .tool-btn,
    .sidebar-toggle,
    .mobile-menu-btn,
    .sidebar-overlay {
        display: none !important;
    }
    
    .document-content {
        padding: 1cm;
        color: black;
    }
    
    
    /* ========== ADDITIONAL FIXES & IMPROVEMENTS ========== */

/* Fix for long words/equations on mobile */
.document-content {
    word-wrap: break-word;
    overflow-wrap: break-word;
    hyphens: auto;
}

/* Better table responsiveness */
.document-content table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

/* Math/equation specific fixes */
.katex-display {
    overflow-x: auto;
    overflow-y: hidden;
    padding: 0.5rem 0;
}

.katex {
    font-size: 1.1em;
}

/* Improve code blocks */
.document-content pre code {
    background: transparent;
    padding: 0;
    color: #00ffff;
}

/* Active chapter highlight animation */
.chapter-item.active {
    animation: glowPulse 2s ease-in-out;
}

@keyframes glowPulse {
    0%, 100% { box-shadow: 0 4px 20px rgba(0, 255, 255, 0.3); }
    50% { box-shadow: 0 4px 30px rgba(0, 255, 255, 0.6); }
}

/* Ensure overlay covers everything properly */
.sidebar-overlay {
    transition: all 0.3s ease;
}

/* Fix for iOS scrolling issues */
.viewer-sidebar,
.document-content {
    -webkit-overflow-scrolling: touch;
}

/* Better focus states for accessibility */
.chapter-item:focus-visible,
.nav-btn:focus-visible,
.tool-btn:focus-visible {
    outline: 2px solid #00ffff;
    outline-offset: 2px;
}

/* Prevent FOUC (Flash of Unstyled Content) */
.physics-viewer-container {
    opacity: 1;
    transition: opacity 0.2s ease;
}

/* Dark mode consistency */
@media (prefers-color-scheme: dark) {
    .viewer-sidebar {
        background: linear-gradient(135deg, rgba(5, 15, 25, 0.98), rgba(2, 8, 15, 0.98));
    }
}

/* Smooth page transitions */
.document-content {
    transition: opacity 0.2s ease;
}

/* Fix for sticky hover on mobile */
@media (max-width: 768px) {
    .chapter-item:hover {
        transform: none;
    }
    
    .tool-btn:hover {
        transform: none;
    }
}

/* Loading state improvements */
.loading-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 300px;
}

.loading-text {
    margin-top: 1rem;
    color: #00ffff;
    font-size: 1rem;
}

/* Error state styling */
.error-container {
    text-align: center;
    padding: 3rem 1rem;
}

.error-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

/* Back to top button (optional) */
.back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: rgba(0, 255, 255, 0.2);
    border: 1px solid #00ffff;
    color: #00ffff;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 100;
    transition: all 0.3s ease;
    backdrop-filter: blur(5px);
}

.back-to-top:hover {
    background: rgba(0, 255, 255, 0.4);
    transform: translateY(-3px);
}

@media (max-width: 768px) {
    .back-to-top {
        bottom: 70px;
        right: 15px;
        width: 35px;
        height: 35px;
    }

    
    
}


/* Fix for mobile menu button visibility */
.mobile-menu-btn {
    display: none;
    background: linear-gradient(45deg, #00ffff, #0099ff) !important;
    border: none !important;
    color: #0a0a1a !important;
    font-weight: bold;
    box-shadow: 0 0 10px rgba(0, 255, 255, 0.5);
}

@media (max-width: 768px) {
    .mobile-menu-btn {
        display: flex !important;
        align-items: center;
        justify-content: center;
        background: linear-gradient(45deg, #00ffff, #0099ff) !important;
        border: none !important;
        color: #0a0a1a !important;
        font-weight: bold;
        width: 44px;
        height: 44px;
        border-radius: 8px;
        cursor: pointer;
        font-size: 24px;
        margin-right: 12px;
        flex-shrink: 0;
        box-shadow: 0 2px 8px rgba(0, 255, 255, 0.3);
        transition: all 0.3s ease;
    }
    
    .mobile-menu-btn:active {
        transform: scale(0.95);
    }
    
    /* Ensure toolbar structure is correct */
    .document-toolbar {
        padding: 0.75rem 1rem;
        min-height: 60px;
    }
    
    .toolbar-left {
        display: flex;
        align-items: center;
        flex: 1;
        min-width: 0;
        gap: 8px;
    }
    
    /* Fix sidebar z-index and positioning */
    .viewer-sidebar {
        z-index: 1001;
    }
    
    .sidebar-overlay {
        z-index: 1000;
    }
}