/* ============================================================
   NovaPivot - Modern Analytics Dashboard Styles
   ============================================================ */

/* --- CSS Variables & Theming --- */
:root {
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --radius: 10px;
    --radius-sm: 6px;
    --radius-xs: 4px;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.08), 0 2px 4px rgba(0,0,0,0.04);
    --shadow-lg: 0 12px 40px rgba(0,0,0,0.12), 0 4px 12px rgba(0,0,0,0.06);
    --transition: 0.2s ease;
}

[data-theme="light"] {
    --bg: #f5f6fa;
    --bg-card: #ffffff;
    --bg-elevated: #ffffff;
    --bg-input: #f0f1f5;
    --bg-hover: #ebedf2;
    --bg-active: #e2e5ec;
    --border: #e0e3eb;
    --border-light: #ebedf2;
    --text: #1a1d2e;
    --text-secondary: #4a5068;
    --text-muted: #8b90a5;
    --accent: #6366f1;
    --accent-hover: #5558e6;
    --accent-light: #eef0ff;
    --accent-bg: rgba(99, 102, 241, 0.08);
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
    --info: #3b82f6;
    --chip-bg: #eef0ff;
    --chip-text: #4338ca;
    --drop-zone-bg: #fafbfd;
    --drop-zone-active: rgba(99, 102, 241, 0.06);
    --drop-zone-hover: rgba(99, 102, 241, 0.12);
    --table-header-bg: #f5f6fa;
    --table-stripe: rgba(0,0,0,0.015);
    --table-hover: rgba(99, 102, 241, 0.04);
    --total-bg: #f0f1f5;
    --grand-total-bg: #e6e8f0;
    --toast-bg: #1a1d2e;
    --toast-text: #ffffff;
}

[data-theme="dark"] {
    --bg: #0f1019;
    --bg-card: #1a1b2e;
    --bg-elevated: #21223a;
    --bg-input: #252640;
    --bg-hover: #2a2c48;
    --bg-active: #33365a;
    --border: #2e3050;
    --border-light: #252740;
    --text: #e8eaf0;
    --text-secondary: #b0b4c8;
    --text-muted: #6b7090;
    --accent: #818cf8;
    --accent-hover: #9198fa;
    --accent-light: #1e1f3a;
    --accent-bg: rgba(129, 140, 248, 0.1);
    --success: #34d399;
    --error: #f87171;
    --warning: #fbbf24;
    --info: #60a5fa;
    --chip-bg: #1e1f3a;
    --chip-text: #a5b4fc;
    --drop-zone-bg: #15162a;
    --drop-zone-active: rgba(129, 140, 248, 0.08);
    --drop-zone-hover: rgba(129, 140, 248, 0.15);
    --table-header-bg: #1e1f35;
    --table-stripe: rgba(255,255,255,0.015);
    --table-hover: rgba(129, 140, 248, 0.06);
    --total-bg: #1e1f35;
    --grand-total-bg: #252745;
    --toast-bg: #e8eaf0;
    --toast-text: #1a1d2e;
}

/* --- Reset & Base --- */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 14px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    transition: background var(--transition), color var(--transition);
}

/* --- Scrollbar --- */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}
::-webkit-scrollbar-track {
    background: transparent;
}
::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* ============================================================
   HEADER
   ============================================================ */
.app-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 56px;
    padding: 0 20px;
    background: var(--bg-card);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background var(--transition), border-color var(--transition);
}

.header-left, .header-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

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

.logo-text {
    font-size: 17px;
    font-weight: 700;
    letter-spacing: -0.3px;
    color: var(--text);
}

/* --- View Tabs --- */
.view-tabs {
    display: flex;
    gap: 2px;
    background: var(--bg-input);
    padding: 3px;
    border-radius: 8px;
}

.view-tab {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    font-size: 12.5px;
    font-weight: 500;
    color: var(--text-muted);
    background: transparent;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: all var(--transition);
    white-space: nowrap;
}

.view-tab:hover {
    color: var(--text-secondary);
    background: var(--bg-hover);
}

.view-tab.active {
    color: var(--text);
    background: var(--bg-card);
    box-shadow: var(--shadow-sm);
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 7px 14px;
    font-family: var(--font);
    font-size: 12.5px;
    font-weight: 500;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition);
    white-space: nowrap;
}

.btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.btn-primary {
    background: var(--accent);
    color: #ffffff;
}
.btn-primary:hover:not(:disabled) {
    background: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.btn-outline {
    background: transparent;
    color: var(--accent);
    border: 1.5px solid var(--accent);
}
.btn-outline:hover:not(:disabled) {
    background: var(--accent-bg);
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
}
.btn-ghost:hover:not(:disabled) {
    background: var(--bg-hover);
    color: var(--text);
}

.btn-sm {
    padding: 4px 10px;
    font-size: 12px;
}

.btn-xs {
    padding: 2px 8px;
    font-size: 11px;
    color: var(--text-muted);
    background: var(--bg-input);
    border: none;
    border-radius: var(--radius-xs);
    cursor: pointer;
}
.btn-xs:hover {
    background: var(--bg-hover);
    color: var(--text);
}

/* --- Theme Toggle --- */
.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border: none;
    border-radius: 8px;
    background: var(--bg-input);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition);
}
.theme-toggle:hover {
    background: var(--bg-hover);
    color: var(--accent);
}

[data-theme="light"] .moon-icon { display: none; }
[data-theme="dark"] .sun-icon { display: none; }

/* ============================================================
   MAIN LAYOUT
   ============================================================ */
.app-main {
    padding: 0;
    min-height: calc(100vh - 56px);
}

.view-content {
    display: none;
    padding: 20px;
    animation: fadeIn 0.3s ease;
}

.view-content.active {
    display: block;
}

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

/* --- Panel / Card --- */
.panel {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: background var(--transition), border-color var(--transition);
}

.panel-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 20px;
    border-bottom: 1px solid var(--border-light);
}

.panel-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--text);
}

.panel-actions {
    display: flex;
    align-items: center;
    gap: 8px;
}

.data-info {
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 400;
}

/* ============================================================
   UPLOAD ZONE
   ============================================================ */
.upload-container {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: calc(100vh - 120px);
}

.upload-zone {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 60px 80px;
    border: 2px dashed var(--border);
    border-radius: 16px;
    background: var(--bg-card);
    transition: all var(--transition);
    cursor: pointer;
    max-width: 520px;
}

.upload-zone:hover, .upload-zone.drag-over {
    border-color: var(--accent);
    background: var(--drop-zone-active);
}

.upload-icon {
    margin-bottom: 20px;
    opacity: 0.7;
}

.upload-title {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text);
}

.upload-subtitle {
    font-size: 14px;
    color: var(--text-muted);
    margin-bottom: 24px;
}

.upload-actions {
    display: flex;
    gap: 12px;
    margin-bottom: 16px;
}

.upload-hint {
    font-size: 12px;
    color: var(--text-muted);
}

/* ============================================================
   DATA TABLE
   ============================================================ */
.table-wrapper {
    overflow: auto;
    max-height: calc(100vh - 180px);
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 12.5px;
}

.data-table th {
    position: sticky;
    top: 0;
    background: var(--table-header-bg);
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 11.5px;
    text-transform: uppercase;
    letter-spacing: 0.4px;
    padding: 10px 14px;
    text-align: left;
    border-bottom: 1px solid var(--border);
    white-space: nowrap;
    z-index: 2;
}

.data-table td {
    padding: 8px 14px;
    border-bottom: 1px solid var(--border-light);
    color: var(--text);
    white-space: nowrap;
    max-width: 250px;
    overflow: hidden;
    text-overflow: ellipsis;
}

.data-table tr:nth-child(even) {
    background: var(--table-stripe);
}

.data-table tr:hover td {
    background: var(--table-hover);
}

/* ============================================================
   PIVOT BUILDER
   ============================================================ */
.pivot-layout {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 20px;
    min-height: calc(100vh - 120px);
}

.builder-sidebar {
    display: flex;
    flex-direction: column;
    gap: 4px;
    max-height: calc(100vh - 100px);
    overflow-y: auto;
    position: sticky;
    top: 76px;
}

.builder-section {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 12px;
    transition: background var(--transition), border-color var(--transition);
}

.builder-section h4 {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.6px;
    color: var(--text-muted);
    margin-bottom: 8px;
}

.builder-section-header {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 8px;
}

.builder-section-header h4 {
    margin-bottom: 0;
}

/* --- Field Search --- */
.field-search {
    width: 100%;
    padding: 6px 10px;
    font-family: var(--font);
    font-size: 12px;
    border: 1px solid var(--border);
    border-radius: var(--radius-xs);
    background: var(--bg-input);
    color: var(--text);
    outline: none;
    transition: all var(--transition);
}

.field-search:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 2px var(--accent-bg);
}

/* --- Drop Zones --- */
.drop-zone {
    min-height: 36px;
    padding: 4px;
    border-radius: var(--radius-xs);
    background: var(--drop-zone-bg);
    border: 1.5px dashed transparent;
    transition: all var(--transition);
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
}

.drop-zone.drop-active {
    border-color: var(--accent);
    background: var(--drop-zone-active);
}

.drop-zone.drop-hover {
    border-color: var(--accent);
    background: var(--drop-zone-hover);
    box-shadow: 0 0 0 3px var(--accent-bg);
}

.drop-zone-placeholder, .drop-zone-empty {
    width: 100%;
    text-align: center;
    padding: 8px;
    font-size: 11.5px;
    color: var(--text-muted);
    pointer-events: none;
}

.field-list {
    max-height: 200px;
    overflow-y: auto;
}

/* --- Field Chips --- */
.field-chip {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 4px 8px;
    background: var(--chip-bg);
    color: var(--chip-text);
    border-radius: var(--radius-xs);
    font-size: 12px;
    font-weight: 500;
    cursor: grab;
    transition: all var(--transition);
    user-select: none;
    white-space: nowrap;
}

.field-chip:hover {
    background: var(--accent-bg);
    box-shadow: var(--shadow-sm);
}

.field-chip.dragging {
    opacity: 0.4;
    transform: scale(0.95);
}

.field-type-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    font-size: 10px;
    font-weight: 700;
    border-radius: 3px;
    background: var(--accent);
    color: #ffffff;
    flex-shrink: 0;
}

.field-label {
    flex: 1;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
}

.field-remove {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    border: none;
    background: transparent;
    color: var(--text-muted);
    font-size: 16px;
    line-height: 1;
    cursor: pointer;
    border-radius: 50%;
    transition: all var(--transition);
    flex-shrink: 0;
}

.field-remove:hover {
    background: var(--error);
    color: #ffffff;
}

/* --- Aggregation Select --- */
.agg-select {
    padding: 1px 4px;
    font-family: var(--font);
    font-size: 10.5px;
    font-weight: 600;
    border: 1px solid var(--border);
    border-radius: 3px;
    background: var(--bg-card);
    color: var(--text-secondary);
    cursor: pointer;
    outline: none;
}

.agg-select:focus {
    border-color: var(--accent);
}

/* ============================================================
   FILTER CONTROLS
   ============================================================ */
.filter-controls {
    margin-top: 4px;
}

.filter-section {
    background: var(--bg-elevated);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xs);
    margin-bottom: 4px;
    overflow: hidden;
}

.filter-section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 6px 10px;
    cursor: pointer;
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
}

.filter-section-header:hover {
    background: var(--bg-hover);
}

.filter-toggle {
    border: none;
    background: transparent;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 10px;
}

.filter-section-body {
    padding: 4px 10px 8px;
    max-height: 160px;
    overflow-y: auto;
}

.filter-quick-controls {
    display: flex;
    gap: 4px;
    margin-bottom: 6px;
}

.filter-item {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 2px 0;
    font-size: 11.5px;
    color: var(--text-secondary);
    cursor: pointer;
}

.filter-item:hover {
    color: var(--text);
}

.filter-item input[type="checkbox"] {
    accent-color: var(--accent);
    width: 13px;
    height: 13px;
}

/* ============================================================
   PIVOT TABLE
   ============================================================ */
.pivot-output {
    min-width: 0;
}

.pivot-table-wrapper {
    overflow: auto;
    max-height: calc(100vh - 160px);
    padding: 0;
}

.pivot-empty-state, .chart-empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 12px;
    padding: 60px 20px;
    color: var(--text-muted);
    font-size: 13px;
    text-align: center;
}

.pivot-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 12.5px;
}

.pivot-table th, .pivot-table td {
    padding: 8px 12px;
    border: 1px solid var(--border-light);
    white-space: nowrap;
}

.pivot-table th {
    background: var(--table-header-bg);
    font-weight: 600;
    font-size: 11.5px;
    color: var(--text-secondary);
    position: sticky;
    top: 0;
    z-index: 2;
}

.pivot-corner {
    background: var(--table-header-bg);
    z-index: 3;
}

.pivot-col-header {
    text-align: center;
}

.pivot-value-header {
    text-align: center;
    font-size: 10.5px;
    text-transform: uppercase;
    letter-spacing: 0.3px;
}

.pivot-row-field-header {
    text-align: left;
}

.pivot-row-label {
    font-weight: 500;
    color: var(--text);
    background: var(--bg-card);
}

.pivot-cell {
    text-align: right;
    font-variant-numeric: tabular-nums;
    color: var(--text);
}

.pivot-total-cell {
    background: var(--total-bg);
    font-weight: 600;
}

.pivot-total-header {
    background: var(--total-bg);
    text-align: center;
    font-weight: 600;
}

.pivot-total-row td, .pivot-total-row th {
    background: var(--total-bg);
    font-weight: 600;
}

.pivot-total-label {
    font-weight: 600;
    color: var(--text);
}

.pivot-grand-total {
    background: var(--grand-total-bg);
    font-weight: 700;
}

.pivot-data-row:hover td {
    background: var(--table-hover);
}

.pivot-data-row:hover .pivot-total-cell {
    background: var(--accent-bg);
}

/* Sortable headers */
.sortable {
    cursor: pointer;
    user-select: none;
    position: relative;
}

.sortable:hover {
    background: var(--bg-hover);
}

.sortable.sort-asc::after {
    content: ' \u25B2';
    font-size: 9px;
    color: var(--accent);
}

.sortable.sort-desc::after {
    content: ' \u25BC';
    font-size: 9px;
    color: var(--accent);
}

.pivot-col-leaf {
    text-align: center;
    font-size: 11px;
}

/* ============================================================
   CHART
   ============================================================ */
.chart-container {
    position: relative;
    min-height: 450px;
    padding: 16px;
}

.chart-container canvas {
    display: block;
    width: 100%;
}

.chart-type-select {
    padding: 5px 10px;
    font-family: var(--font);
    font-size: 12px;
    font-weight: 500;
    border: 1px solid var(--border);
    border-radius: var(--radius-xs);
    background: var(--bg-input);
    color: var(--text);
    cursor: pointer;
    outline: none;
}

.chart-type-select:focus {
    border-color: var(--accent);
}

/* --- Chart Tooltip --- */
.chart-tooltip {
    display: none;
    position: fixed;
    z-index: 1000;
    background: var(--toast-bg);
    color: var(--toast-text);
    padding: 8px 12px;
    border-radius: var(--radius-sm);
    font-size: 12px;
    line-height: 1.5;
    pointer-events: none;
    box-shadow: var(--shadow-lg);
    max-width: 250px;
}

/* ============================================================
   TOAST NOTIFICATIONS
   ============================================================ */
.toast-container {
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 9999;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.toast {
    padding: 10px 18px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    font-weight: 500;
    color: var(--toast-text);
    background: var(--toast-bg);
    box-shadow: var(--shadow-lg);
    transform: translateX(120%);
    transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    max-width: 360px;
}

.toast.show {
    transform: translateX(0);
}

.toast-success {
    border-left: 3px solid var(--success);
}

.toast-error {
    border-left: 3px solid var(--error);
}

.toast-info {
    border-left: 3px solid var(--info);
}

.toast-warning {
    border-left: 3px solid var(--warning);
}

/* ============================================================
   FOOTER
   ============================================================ */
.app-footer {
    text-align: center;
    padding: 16px 20px;
    font-size: 12.5px;
    color: var(--text-muted);
    border-top: 1px solid var(--border);
    background: var(--bg-card);
    transition: background var(--transition), border-color var(--transition), color var(--transition);
}

.app-footer a {
    color: var(--accent);
    text-decoration: none;
    font-weight: 500;
}

.app-footer a:hover {
    text-decoration: underline;
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1024px) {
    .pivot-layout {
        grid-template-columns: 1fr;
    }

    .builder-sidebar {
        position: static;
        max-height: none;
        flex-direction: row;
        flex-wrap: wrap;
        gap: 8px;
    }

    .builder-section {
        flex: 1;
        min-width: 200px;
    }

    .field-list {
        max-height: 120px;
    }
}

@media (max-width: 768px) {
    .app-header {
        flex-wrap: wrap;
        height: auto;
        padding: 10px 14px;
        gap: 8px;
    }

    .header-center {
        order: 3;
        width: 100%;
    }

    .view-tabs {
        width: 100%;
        justify-content: center;
    }

    .view-tab span:not(.view-tab svg) {
        display: none;
    }

    .header-right .btn span:not(svg) {
        display: none;
    }

    .upload-zone {
        padding: 40px 30px;
    }

    .view-content {
        padding: 12px;
    }

    .builder-sidebar {
        flex-direction: column;
    }

    .builder-section {
        min-width: 100%;
    }

    .pivot-table-wrapper {
        max-height: calc(100vh - 200px);
    }
}

@media (max-width: 480px) {
    .upload-actions {
        flex-direction: column;
    }

    .view-tab {
        padding: 6px 10px;
        font-size: 11.5px;
    }
}