:root {
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-sidebar: #1e293b;
    --text-primary: #334155;
    --text-secondary: #64748b;
    --text-sidebar: #e2e8f0;
    --text-sidebar-muted: #94a3b8;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --border-color: #e2e8f0;
    --hover-bg: #f1f5f9;
    --header-height: 64px;
    --sidebar-width: 280px;
    --shadow-sm: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --font-mono: 'JetBrains Mono', monospace;
    --font-sans: 'Inter', sans-serif;
}

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

body {
    font-family: var(--font-sans);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    height: 100vh;
    overflow: hidden;
}

.app-container {
    display: flex;
    height: 100vh;
}

/* Sidebar Styling */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--bg-sidebar);
    color: var(--text-sidebar);
    display: flex;
    flex-direction: column;
    border-right: 1px solid #334155;
    flex-shrink: 0;
}

.sidebar-header {
    padding: 1.5rem;
    border-bottom: 1px solid #334155;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.sidebar-header h2 {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.025em;
}

.version {
    font-size: 0.75rem;
    color: var(--text-sidebar-muted);
    background: #334155;
    padding: 2px 6px;
    border-radius: 4px;
}

.search-container {
    padding: 1rem;
    border-bottom: 1px solid #334155;
}

#table-search {
    width: 100%;
    background: #0f172a;
    border: 1px solid #334155;
    color: var(--text-sidebar);
    padding: 0.5rem 0.75rem;
    border-radius: 6px;
    font-size: 0.875rem;
    outline: none;
    transition: border-color 0.2s;
}

#table-search:focus {
    border-color: var(--accent-color);
}

.tables-list-container {
    flex: 1;
    overflow-y: auto;
    padding: 0.5rem;
}

.tables-list {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.table-item {
    padding: 0.625rem 1rem;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 0.875rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-sidebar-muted);
}

.table-item:hover {
    background-color: #334155;
    color: var(--text-sidebar);
}

.table-item.active {
    background-color: var(--accent-color);
    color: white;
}

.table-badge {
    font-size: 0.65rem;
    padding: 2px 5px;
    border-radius: 3px;
    background: #334155;
    color: var(--text-sidebar-muted);
    font-weight: 600;
}

.table-item.active .table-badge {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

/* Main Content Styling */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: var(--bg-primary);
}

.top-bar {
    height: var(--header-height);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
    flex-shrink: 0;
}

.breadcrumbs {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.95rem;
}

.crumb-root {
    color: var(--text-secondary);
    font-weight: 500;
}

.crumb-separator {
    color: #cbd5e1;
}

.crumb-active {
    color: var(--text-primary);
    font-weight: 600;
}

.icon-btn {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 6px;
    color: var(--text-secondary);
    transition: all 0.2s;
}

.icon-btn:hover {
    background: var(--hover-bg);
    color: var(--text-primary);
}

/* Empty State */
.empty-state {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--text-secondary);
}

.empty-icon {
    margin-bottom: 1rem;
    color: #cbd5e1;
}

.empty-content h3 {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

/* Content Wrapper */
.content-wrapper {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    padding: 1.5rem 2rem;
}

.content-wrapper.hidden {
    display: none;
}

/* Tabs */
.tabs {
    display: flex;
    gap: 2rem;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 1.5rem;
    flex-shrink: 0;
}

.tab-btn {
    background: none;
    border: none;
    padding: 0.75rem 0;
    font-size: 0.95rem;
    color: var(--text-secondary);
    cursor: pointer;
    position: relative;
    font-weight: 500;
    transition: color 0.2s;
}

.tab-btn:hover {
    color: var(--text-primary);
}

.tab-btn.active {
    color: var(--accent-color);
    font-weight: 600;
}

.tab-btn.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--accent-color);
}

.tab-pane {
    display: none;
    flex: 1;
    flex-direction: column;
    overflow: hidden;
}

.tab-pane.active {
    display: flex;
}

/* Data Table Styling */
.data-controls {
    display: flex;
    justify-content: space-between;
    margin-bottom: 1rem;
    flex-shrink: 0;
}

.search-box input {
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    width: 300px;
    font-size: 0.875rem;
    outline: none;
}

.search-box input:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.1);
}

.pagination-controls {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.pagination-controls select {
    padding: 0.4rem 0.5rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background: white;
    font-size: 0.875rem;
}

.pagination-nav button {
    padding: 0.4rem 0.8rem;
    border: 1px solid var(--border-color);
    background: white;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.875rem;
    transition: all 0.2s;
}

.pagination-nav button:hover:not(:disabled) {
    background: var(--hover-bg);
}

.pagination-nav button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.table-scroll-container {
    flex: 1;
    overflow: auto;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background: white;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.875rem;
}

th {
    background: #f8fafc;
    padding: 0.75rem 1rem;
    text-align: left;
    font-weight: 600;
    color: var(--text-primary);
    position: sticky;
    top: 0;
    border-bottom: 1px solid var(--border-color);
    white-space: nowrap;
    cursor: default;
    user-select: none;
}

th.sortable-th {
    cursor: pointer;
}

th.sortable-th:hover {
    background: #f1f5f9;
    color: var(--accent-color);
}

th.sortable-th:hover .sort-icon-neutral {
    opacity: 1;
}

th.th-sorted {
    background: #eff6ff;
    color: var(--accent-color);
    border-bottom-color: var(--accent-color);
}

.th-content {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

.sort-icon {
    font-size: 0.75rem;
    line-height: 1;
}

.sort-icon-neutral {
    opacity: 0.3;
    font-size: 0.7rem;
    transition: opacity 0.15s;
}

td.td-sorted {
    background: #f0f7ff;
}

td {
    padding: 0.75rem 1rem;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-secondary);
    white-space: nowrap;
    max-width: 300px;
    overflow: hidden;
    text-overflow: ellipsis;
}

tr:hover {
    background: #f8fafc;
}

/* Structure Table */
.structure-table th,
.structure-table td {
    padding: 0.75rem 1.5rem;
}

.structure-table td {
    font-family: var(--font-mono);
}

.tag {
    display: inline-block;
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 600;
}

.tag-pk {
    background: #fee2e2;
    color: #ef4444;
}

.tag-fk {
    background: #dbeafe;
    color: #3b82f6;
}

/* Relationships */
.relationships-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    height: 100%;
    overflow: hidden;
}

.relationship-card {
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.relationship-card h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.rel-list {
    flex: 1;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.rel-item {
    padding: 0.75rem;
    background: #f8fafc;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-family: var(--font-mono);
    font-size: 0.85rem;
}

.rel-arrow {
    color: #cbd5e1;
    margin: 0 0.5rem;
}

/* Loading */
.loading-spinner {
    width: 24px;
    height: 24px;
    border: 2px solid #e2e8f0;
    border-top-color: var(--accent-color);
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
    margin: 2rem auto;
}

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

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #94a3b8;
}