:root {
    --bg-color: #121212;
    --sidebar-bg: #1e1e1e;
    --card-bg: #252525;
    --text-primary: #e0e0e0;
    --text-secondary: #aaaaaa;
    --accent: #00e5ff;
    --accent-hover: #00b8cc;
    --border: #333;
    --danger: #ff5252;
    --success: #69f0ae;
    --rail-width: clamp(60px, 8vw, 80px);
    --sidebar-width: clamp(250px, 20vw, 320px);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body, html {
    height: 100%;
    margin: 0;
    overflow: hidden; /* Prevent body scroll, handle in containers */
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
}

/* -----------------------------------------------------------
   LAYOUT STRUCTURE
   ----------------------------------------------------------- */
.app-layout {
    display: flex;
    flex-direction: column;
    height: 100%;
    width: 100%;
}

/* Header */
.top-header {
    height: 50px;
    background-color: var(--bg-color);
    display: flex;
    align-items: center;
    padding: 0 20px;
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
    z-index: 30;
}

/* Main Container (Rail | Sidebar | Content) */
.app-container {
    display: flex;
    flex: 1; /* Take remaining height */
    overflow: hidden;
    position: relative;
    flex-direction: row;
}

/* 1. Navigation Rail (Leftmost Strip) */
.nav-rail {
    width: var(--rail-width); /* Standard rail width */
    background-color: #151515;
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    z-index: 50; /* Top most on left */
    align-items: center;
    padding-top: 10px;
    position: relative; /* Ensure z-index works */
}

.rail-button {
    background: transparent;
    border: none;
    color: #666;
    width: 100%;
    padding: 15px 0;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 5px;
    transition: all 0.2s;
}

.rail-button:hover {
    color: #eee;
    background-color: rgba(255,255,255,0.05);
}

.rail-button.active {
    color: var(--accent);
    border-left: 3px solid var(--accent); /* Indicator on left */
    background-color: rgba(0, 229, 255, 0.05);
}

.rail-button .icon { font-size: 24px; display: block; }
.rail-button .label { font-size: 11px; display: block; margin-top: 4px; }

/* 2. Sidebar Drawer (Flex Panel) */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--sidebar-bg);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    z-index: 10;
    transition: margin-left 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
    margin-left: 0; /* Visible */
}

.sidebar.collapsed {
    margin-left: calc(-1 * var(--sidebar-width)); /* Hidden (Slide Left) */
}

/* Sidebar Section (Units, Equip, etc.) */
.sidebar-section {
    display: none; /* Toggled via JS */
    flex-direction: column;
    height: 100%;
    overflow: hidden;
}

.sidebar-section.active-tab {
    display: flex;
}

/* Toolbar inside Sidebar */
.sidebar-toolbar {
    padding: 15px;
    border-bottom: 1px solid var(--border);
    background-color: #222;
    display: flex;
    gap: 10px;
    align-items: center;
    flex-shrink: 0;
}

.sidebar-toolbar input {
    flex: 1;
    background: #111;
    border: 1px solid #333;
    color: #fff;
    padding: 6px 10px;
    border-radius: 4px;
}

/* Content List inside Sidebar */
.sidebar-content {
    flex: 1;
    overflow-y: auto;
    padding: 10px 0;
    background-color: var(--sidebar-bg);
}

/* Tree View Styling */
.tree-view {
    padding: 0 10px;
}

.tree-node {
    margin-left: 15px;
    border-left: 1px solid #333;
    padding-left: 5px;
}
/* Root nodes don't need margin */
.tree-view > .tree-node {
    margin-left: 0;
    border-left: none;
    padding-left: 0; 
    margin-bottom: 5px;
}

.node-content {
    display: flex;
    align-items: center;
    padding: 8px 10px;
    cursor: pointer;
    border-radius: 4px;
    color: #ccc;
    transition: background 0.1s;
    user-select: none;
}

.node-content:hover {
    background-color: rgba(255,255,255,0.05);
    color: #fff;
}

.node-content.active {
    background-color: rgba(0, 229, 255, 0.15);
    color: var(--accent);
}

.node-content img {
    margin-right: 8px;
    width: 20px; height: 20px;
    object-fit: cover;
    border-radius: 2px;
}

.toggle-icon {
    width: 20px;
    text-align: center;
    color: #666;
    font-size: 10px;
}


/* 3. Main Content Area */
.main-content {
    flex: 1;
    overflow-y: auto;
    background-color: var(--bg-color);
    padding: 30px;
    position: relative;
    /* Center empty state */
    display: flex; 
    flex-direction: column;
}

/* Details Views */
.details-view {
    max-width: 1000px;
    margin: 0 auto;
    width: 100%;
    display: block; /* Override flex */
}

/* Empty State */
.empty-state {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: #555;
    text-align: center;
}
.empty-state .icon { font-size: 64px; margin-bottom: 20px; opacity: 0.3; }


/* -----------------------------------------------------------
   COMMON COMPONENTS
   ----------------------------------------------------------- */

/* Breadcrumbs */
.breadcrumbs { font-size: 14px; }
.crumb-link { color: #888; text-decoration: none; }
.crumb-current { color: var(--text-primary); font-weight: 600; margin-left: 5px; }

/* Badges */
.badge {
    background: #333;
    color: #eee;
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 0.8em;
    border: 1px solid #444;
}

/* Buttons */
.icon-btn {
    background: none; border: none; color: var(--accent);
    cursor: pointer; font-size: 1.2em;
    padding: 5px;
}
.primary-btn {
    background: var(--accent);
    color: #000;
    border: none;
    padding: 8px 16px;
    border-radius: 4px;
    font-weight: 600;
    cursor: pointer;
}
.secondary-btn {
    background: transparent;
    color: #ccc;
    border: 1px solid #555;
    padding: 8px 16px;
    border-radius: 4px;
    cursor: pointer;
}
.danger-btn {
    background: #500;
    color: #fff;
    border: 1px solid #f00;
    padding: 8px 16px;
    border-radius: 4px;
    cursor: pointer;
}
.small-btn {
    padding: 4px 10px; font-size: 0.85em;
    background: #222; border: 1px solid #444; color: #ccc;
    cursor: pointer; border-radius: 3px;
}

/* Forms */
.form-group { margin-bottom: 15px; }
.form-group label { display: block; margin-bottom: 6px; color: #888; font-size: 0.9em; }
.form-control, input[type=text], textarea, select {
    width: 100%;
    background: #111;
    border: 1px solid #444;
    color: #eee;
    padding: 10px;
    border-radius: 4px;
    font-family: inherit;
}
.form-control:focus { outline: none; border-color: var(--accent); }

/* Loading */
.loading { padding: 20px; text-align: center; color: #666; font-style: italic; }

/* Modals */
.modal {
    display: none;
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.8);
    z-index: 1000;
    justify-content: center; align-items: center;
    backdrop-filter: blur(2px);
}
.modal.active { display: flex; }
.modal-content {
    background: #1f1f1f;
    border: 1px solid #444;
    padding: 30px;
    border-radius: 8px;
    width: 500px;
    max-width: 90%;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}
.modal-actions {
    margin-top: 25px;
    display: flex; justify-content: flex-end; gap: 10px;
}

/* Sections in Detail View */
.section {
    background: #1a1a1a;
    border: 1px solid #333;
    border-radius: 6px;
    padding: 20px;
    margin-bottom: 20px;
}
.section-header {
    display: flex; justify-content: space-between; align-items: center;
    margin-bottom: 15px; padding-bottom: 10px;
    border-bottom: 1px solid #2a2a2a;
}
.section h3 { margin: 0; font-size: 1.1em; color: var(--accent); }

/* Paste Targets */
.paste-target {
    border: 2px dashed #444;
    transition: all 0.2s;
    cursor: pointer;
}
.paste-target:focus {
    border-color: var(--accent);
    background: rgba(0, 229, 255, 0.05);
}

/* Tables */
.data-table { width: 100%; border-collapse: collapse; }
.data-table th { text-align: left; padding: 10px; color: #666; border-bottom: 1px solid #333; font-weight: normal; }
.data-table td { padding: 10px; border-bottom: 1px solid #222; }
.data-table tr:last-child td { border-bottom: none; }

/* ...existing code... */

/* -----------------------------------------------------------
   GRID VIEW (Rectangles / Cards)
   ----------------------------------------------------------- */
.grid-view-container {
    padding: 20px;
    display: none; /* Toggled */
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
    width: 100%;
}

.grid-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 6px;
    overflow: hidden;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
    display: flex;
    flex-direction: column;
}

.grid-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    border-color: var(--accent);
}

.card-image {
    width: 100%;
    height: 120px;
    background-color: #2a2a2a; /* Darker bg to match placeholder */
    object-fit: contain; /* Prevent cropping */
    padding: 10px; /* Add breathing room */
    border-bottom: 1px solid var(--border);
}

.card-placeholder {
    width: 100%;
    height: 120px;
    background-color: #2a2a2a;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #555;
    font-size: 2em;
    border-bottom: 1px solid var(--border);
}

.card-content {
    padding: 15px;
    text-align: center;
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.card-title {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 1.1em;
}

.card-subtitle {
    font-size: 0.8em;
    color: var(--text-secondary);
    margin-top: 5px;
}

/* --- Detail View Headers --- */
.details-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border);
}
.unit-title-row {
    display: flex;
    align-items: center;
    gap: 15px;
}
.unit-title-row h1 {
    margin: 0;
    font-size: 1.8em;
    line-height: 1;
}
/* Nav Arrows */
#btn-unit-back, #btn-unit-forward {
    font-size: 1.6em; /* Bigger arrows */
    padding: 2px 8px; /* Tighter padding */
    background: rgba(255,255,255,0.05);
    border-radius: 4px;
    transition: background 0.2s;
    /* Ensure they appear before anything else visually if order matches */
}
#btn-unit-back:hover, #btn-unit-forward:hover {
    background: rgba(255,255,255,0.1);
    color: var(--accent-hover);
}
/* Ensure unit image in title row behaves nicely */
#unit-main-image {
    max-width: 60px;
    max-height: 60px;
    object-fit: contain;
    border-radius: 6px;
    border: 1px solid var(--border);
    background-color: var(--card-bg); /* Add bg because contain might show empty space */
}

/* Equipment Tiles */
.equip-tile {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 15px;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 10px;
}
.equip-tile:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}
.equip-tile img {
    width: 64px;
    height: 64px;
    object-fit: cover;
    border-radius: 4px;
    margin-bottom: 5px;
}
.equip-tile h4 {
    margin: 0;
    font-size: 1rem;
    color: var(--text-primary);
}
.equip-tile span {
    font-size: 0.8rem;
    color: var(--text-secondary);
}


/* Action Buttons Group */
#view-actions, #edit-actions {
    display: flex;
    gap: 10px;
    align-items: center;
}


/* Unit Tabs */
.unit-tabs-nav {
    display: flex;
    gap: 2px;
    margin-bottom: 20px;
    border-bottom: 1px solid var(--border);
}

.tab-btn {
    background: transparent;
    border: 1px solid transparent;
    border-bottom: none;
    padding: 10px 20px;
    color: var(--text-secondary);
    cursor: pointer;
    border-radius: 4px 4px 0 0;
    transition: all 0.2s;
    font-weight: 500;
}

.tab-btn:hover {
    color: var(--text-primary);
    background: rgba(255,255,255,0.02);
}

.tab-btn.active {
    background: var(--bg-color); /* Same as page bg */
    border-color: var(--border);
    color: var(--text-primary);
    position: relative;
    top: 1px; /* Cover bottom border */
    border-bottom: 1px solid var(--bg-color);
}

.tab-content {
    animation: fadeIn 0.2s ease-in-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(5px); }
    to { opacity: 1; transform: translateY(0); }
}


/* Modal Form Improvements */
.modal-content input[type="text"],
.modal-content input[type="number"],
.modal-content select {
    background-color: var(--input-bg);
    color: var(--text-main);
    border: 1px solid var(--border);
    padding: 8px 12px;
    border-radius: 4px;
    width: 100%;
    margin-bottom: 5px;
}

.modal-content .form-group {
    margin-bottom: 15px;
}

.modal-content label {
    display: block;
    margin-bottom: 5px;
    color: var(--text-muted);
}

.modal-content .row {
    display: flex;
    gap: 10px;
}

/* Settings Sidebar Navigation */
.settings-nav-btn {
    display: block;
    width: 100%;
    text-align: left;
    background: transparent;
    border: none;
    color: #bbb;
    padding: 10px 15px;
    cursor: pointer;
    font-size: 14px;
    border-left: 3px solid transparent;
}
.settings-nav-btn:hover {
    color: #fff;
    background: rgba(255,255,255,0.05);
}
.settings-nav-btn.active {
    color: var(--accent);
    background: rgba(0, 229, 255, 0.1);
    border-left-color: var(--accent);
}