:root {
    --header-height: 60px;
    --sidebar-width: 350px;
    --primary-color: #c00;
    --text-color: #333;
    --bg-color: #f4f4f4;
    --sidebar-bg: #2c3e50;
    --sidebar-text: #ecf0f1;
    --sidebar-hover: #34495e;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    height: 100vh;
    overflow: hidden;
}

.app-container {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.app-header {
    height: var(--header-height);
    background-color: white;
    border-bottom: 1px solid #ddd;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    z-index: 10;
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo {
    height: 32px;
}

.brand h1 {
    margin: 0;
    font-size: 1.2rem;
    font-weight: 600;
}

.controls {
    display: flex;
    gap: 15px;
}

select, input {
    padding: 8px;
    border: 1px solid #ccc;
    border-radius: 4px;
}

.main-layout {
    display: flex;
    flex: 1;
    overflow: hidden;
}

.sidebar {
    width: var(--sidebar-width);
    background-color: var(--sidebar-bg);
    color: var(--sidebar-text);
    overflow-y: auto;
    display: flex;
    flex-direction: column;
}

.content-viewer {
    flex: 1;
    overflow: auto;
    background: white;
    padding: 0; /* Reset padding as legacy content has its own margins */
    position: relative;
}

.tree-nav {
    padding: 10px;
    font-size: 0.9rem;
}

.tree-nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.tree-item {
    cursor: pointer;
    padding: 4px 8px;
    border-radius: 3px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.tree-item:hover {
    background-color: var(--sidebar-hover);
}

.tree-item.selected {
    background-color: var(--primary-color);
    color: white;
}

.tree-nav .tree-children {
    padding-left: 20px;
    display: none;
}

.tree-children.open {
    display: block;
}

.tree-toggle {
    display: inline-block;
    width: 16px;
    text-align: center;
    margin-right: 4px;
    color: #aaa;
}

.content-area {
    flex: 1;
    background-color: white;
    position: relative;
    display: flex;
    flex-direction: column;
}

.breadcrumbs {
    padding: 8px 20px;
    background-color: #f9f9f9;
    border-bottom: 1px solid #eee;
    font-size: 0.9rem;
    color: #555;
    flex-shrink: 0;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.breadcrumbs span.sep {
    margin: 0 5px;
    color: #999;
}

.breadcrumbs a {
    text-decoration: none;
    color: #0066cc;
    cursor: pointer;
}

.breadcrumbs a:hover {
    text-decoration: underline;
}

.breadcrumbs .current {
    color: #333;
    font-weight: 600;
}

iframe {
    width: 100%;
    height: 100%;
    border: none;
}

.placeholder {
    padding: 20px;
    color: #888;
    text-align: center;
}

/* Lightbox Styles */
.lightbox-overlay {
    display: none;
    position: fixed;
    z-index: 10000;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    align-items: center;
    justify-content: center;
}

.lightbox-overlay.active {
    display: flex;
}

.lightbox-content {
    max-width: 95%;
    max-height: 95%;
    box-shadow: 0 0 20px rgba(0,0,0,0.5);
    border-radius: 4px;
}

.lightbox-close {
    position: absolute;
    top: 20px;
    right: 30px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    cursor: pointer;
    transition: 0.3s;
}

.lightbox-close:hover,
.lightbox-close:focus {
    color: #bbb;
    text-decoration: none;
    cursor: pointer;
}

/* Zoomable Image Feedback */
.zoomable {
    cursor: zoom-in;
    cursor: -webkit-zoom-in;
    transition: transform 0.2s ease;
}

.zoomable:hover {
    transform: scale(1.01);
    box-shadow: 0 0 5px rgba(0,0,0,0.2);
}