/* ===================================================================
   main.css — layout, base styles, CSS custom properties
   =================================================================== */

/* ── Custom Properties ──────────────────────────────────────────── */
:root {
  --primary:        #2563eb;
  --primary-dark:   #1d4ed8;
  --primary-light:  #dbeafe;
  --secondary:      #64748b;
  --bg:             #f1f5f9;
  --bg-panel:       #ffffff;
  --bg-sidebar:     #f8fafc;
  --border:         #e2e8f0;
  --border-dark:    #cbd5e1;
  --text:           #1e293b;
  --text-muted:     #64748b;
  --text-light:     #94a3b8;
  --success:        #16a34a;
  --warning:        #d97706;
  --danger:         #dc2626;
  --danger-light:   #fee2e2;

  /* Variable type colors */
  --c-numeric:      #2563eb;
  --c-categorical:  #7c3aed;
  --c-date:         #0891b2;
  --c-string:       #64748b;

  /* Layout dimensions */
  --header-h:       48px;
  --tabnav-h:       40px;
  --sidebar-w:      220px;
  --config-w:       320px;

  /* Spacing */
  --sp-xs: 4px;
  --sp-sm: 8px;
  --sp-md: 16px;
  --sp-lg: 24px;
  --sp-xl: 32px;

  /* Radius */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 10px;

  /* Shadow */
  --shadow-sm: 0 1px 3px rgba(0,0,0,.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,.12);
  --shadow-lg: 0 8px 32px rgba(0,0,0,.16);

  /* Font */
  --font: 'Segoe UI', 'Noto Sans Thai', system-ui, -apple-system, sans-serif;
  --font-mono: 'Consolas', 'Courier New', monospace;
  --font-size-base: 13px;
  --font-size-sm:   12px;
  --font-size-xs:   11px;
  --font-size-lg:   15px;
}

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

html, body {
  height: 100%;
  overflow: hidden; /* full-viewport app */
}

body {
  font-family: var(--font);
  font-size: var(--font-size-base);
  color: var(--text);
  background: var(--bg);
  display: flex;
  flex-direction: column;
}

/* ── App Header ─────────────────────────────────────────────────── */
.app-header {
  height: var(--header-h);
  background: var(--bg-panel);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: var(--sp-md);
  padding: 0 var(--sp-md);
  flex-shrink: 0;
  box-shadow: var(--shadow-sm);
  z-index: 100;
}

.header-brand {
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
  flex-shrink: 0;
}

.brand-icon {
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
  line-height: 1;
}

.brand-name {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -.3px;
}

.brand-sep {
  color: var(--border-dark);
  font-weight: 300;
}

.brand-sub {
  font-size: var(--font-size-sm);
  color: var(--text-muted);
}

.header-dataset {
  flex: 1;
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
  min-width: 0;
}

.dataset-name {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 260px;
}

.dataset-meta {
  font-size: var(--font-size-xs);
  color: var(--text-muted);
  white-space: nowrap;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
  flex-shrink: 0;
}

/* ── Tab Navigation ─────────────────────────────────────────────── */
.tab-nav {
  height: var(--tabnav-h);
  background: var(--bg-panel);
  border-bottom: 2px solid var(--border);
  display: flex;
  align-items: stretch;
  gap: 0;
  padding: 0 var(--sp-sm);
  flex-shrink: 0;
  overflow-x: auto;
  scrollbar-width: none;
}

.tab-nav::-webkit-scrollbar { display: none; }

.tab-btn {
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 0 var(--sp-md);
  font-size: var(--font-size-sm);
  font-family: var(--font);
  color: var(--text-muted);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  cursor: pointer;
  white-space: nowrap;
  transition: color .15s, border-color .15s;
  outline: none;
}

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

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

/* ── App Layout ─────────────────────────────────────────────────── */
.app-layout {
  flex: 1;
  display: flex;
  overflow: hidden;
  min-height: 0;
}

/* ── Variable Panel (Left Sidebar) ─────────────────────────────── */
.variable-panel {
  width: var(--sidebar-w);
  flex-shrink: 0;
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--sp-sm) var(--sp-md);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.panel-title {
  font-size: var(--font-size-sm);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .5px;
  color: var(--text-muted);
}

.var-search-wrap {
  padding: var(--sp-sm);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.var-search {
  width: 100%;
  padding: 5px var(--sp-sm);
  font-size: var(--font-size-sm);
  font-family: var(--font);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg-panel);
  color: var(--text);
  outline: none;
}

.var-search:focus { border-color: var(--primary); }

.var-type-legend {
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
  padding: 4px var(--sp-md);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.type-legend-item { display: flex; align-items: center; }

.var-list {
  flex: 1;
  overflow-y: auto;
  padding: var(--sp-xs) 0;
}

.var-empty {
  padding: var(--sp-xl) var(--sp-md);
  text-align: center;
  color: var(--text-light);
  font-size: var(--font-size-sm);
}

.var-empty-sub {
  margin-top: var(--sp-xs);
  font-size: var(--font-size-xs);
}

/* Variable item in sidebar */
.var-item {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px var(--sp-md);
  cursor: pointer;
  border-radius: 0;
  transition: background .1s;
  user-select: none;
}

.var-item:hover { background: var(--primary-light); }
.var-item.selected { background: #dbeafe; }

.var-item-name {
  font-size: var(--font-size-sm);
  color: var(--text);
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* Type icons (used in sidebar and data grid) */
.type-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 18px;
  height: 18px;
  border-radius: 3px;
  font-size: 10px;
  font-weight: 700;
  flex-shrink: 0;
}

.type-icon.type-numeric     { background: #dbeafe; color: var(--c-numeric); }
.type-icon.type-categorical { background: #ede9fe; color: var(--c-categorical); }
.type-icon.type-date        { background: #cffafe; color: var(--c-date); }
.type-icon.type-string      { background: #f1f5f9; color: var(--c-string); }

/* ── Tab Content Area ───────────────────────────────────────────── */
.tab-content-area {
  flex: 1;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.tab-pane {
  display: none;
  flex: 1;
  overflow: hidden;
  flex-direction: column;
  min-height: 0;
}

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

/* ── Data Tab ───────────────────────────────────────────────────── */
.data-toolbar {
  height: 36px;
  background: var(--bg-panel);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
  padding: 0 var(--sp-md);
  flex-shrink: 0;
}

.toolbar-sep {
  width: 1px;
  height: 18px;
  background: var(--border);
  flex-shrink: 0;
}

.toolbar-fill { flex: 1; }

.row-info {
  font-size: var(--font-size-xs);
  color: var(--text-muted);
}

/* Empty state */
.data-empty-state {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--sp-md);
  color: var(--text-muted);
}

.empty-icon {
  font-size: 48px;
  line-height: 1;
  opacity: .5;
}

.data-empty-state h3 {
  font-size: var(--font-size-lg);
  color: var(--text);
}

.data-empty-state p {
  font-size: var(--font-size-sm);
  color: var(--text-muted);
  text-align: center;
  max-width: 320px;
}

.empty-actions {
  display: flex;
  gap: var(--sp-sm);
}

/* Data grid container */
.data-grid-outer {
  flex: 1;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  position: relative;
}

.data-grid-scroll {
  flex: 1;
  overflow: auto;
  position: relative;
}

/* ── Analysis Layout ────────────────────────────────────────────── */
.analysis-layout {
  flex: 1;
  display: flex;
  overflow: hidden;
  min-height: 0;
}

.analysis-config {
  width: var(--config-w);
  flex-shrink: 0;
  background: var(--bg-panel);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.config-header {
  padding: var(--sp-md);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.config-title {
  font-size: var(--font-size-lg);
  font-weight: 700;
  color: var(--text);
}

.config-subtitle {
  font-size: var(--font-size-xs);
  color: var(--text-muted);
  margin-top: 2px;
}

.config-body {
  flex: 1;
  overflow-y: auto;
  padding: var(--sp-md);
}

.config-footer {
  padding: var(--sp-md);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}

.config-divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: var(--sp-md) 0;
}

/* Analysis output panel */
.analysis-output {
  flex: 1;
  overflow-y: auto;
  padding: var(--sp-lg);
  min-width: 0;
  background: var(--bg);
}

.output-placeholder {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-light);
  font-size: var(--font-size-sm);
}

/* Sub-tabs within analysis panels */
.sub-tab-nav {
  display: flex;
  gap: 0;
  margin-top: var(--sp-sm);
  border-bottom: 1px solid var(--border);
}

.sub-tab-btn {
  padding: 4px var(--sp-sm);
  font-size: var(--font-size-xs);
  font-family: var(--font);
  color: var(--text-muted);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  cursor: pointer;
  white-space: nowrap;
  transition: color .12s;
}

.sub-tab-btn.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
  font-weight: 600;
}

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

/* Form fields */
.field-group { margin-bottom: var(--sp-md); }

.field-label {
  display: block;
  font-size: var(--font-size-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .4px;
  color: var(--text-muted);
  margin-bottom: var(--sp-xs);
}

.checkbox-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4px;
}

.checkbox-item {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: var(--font-size-sm);
  color: var(--text);
  cursor: pointer;
}

.checkbox-item input[type="checkbox"] {
  cursor: pointer;
  accent-color: var(--primary);
}

/* Variable selector drop zone */
.var-selector {
  min-height: 64px;
  border: 2px dashed var(--border-dark);
  border-radius: var(--radius-md);
  padding: var(--sp-sm);
  display: flex;
  flex-direction: column;
  gap: 4px;
  transition: border-color .15s, background .15s;
}

.var-selector.drag-over {
  border-color: var(--primary);
  background: var(--primary-light);
}

.var-selector-empty {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-xs);
  color: var(--text-light);
  text-align: center;
  min-height: 40px;
}

/* Selected variable chip in selector */
.var-chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px var(--sp-sm);
  border-radius: 100px;
  font-size: var(--font-size-xs);
  font-weight: 500;
  background: var(--primary-light);
  color: var(--primary);
}

.var-chip-remove {
  cursor: pointer;
  opacity: .6;
  font-size: 12px;
  line-height: 1;
}

.var-chip-remove:hover { opacity: 1; }

/* Coming soon placeholder in config body */
.coming-soon-config {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 120px;
  color: var(--text-light);
  font-size: var(--font-size-sm);
  font-style: italic;
}

/* ── Toast Notifications ────────────────────────────────────────── */
.toast-container {
  position: fixed;
  bottom: var(--sp-lg);
  right: var(--sp-lg);
  display: flex;
  flex-direction: column;
  gap: var(--sp-sm);
  z-index: 9999;
  pointer-events: none;
}

.toast {
  padding: 10px var(--sp-md);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  box-shadow: var(--shadow-md);
  animation: toastIn .2s ease;
  pointer-events: auto;
  max-width: 360px;
}

.toast.success { background: #166534; color: #fff; }
.toast.error   { background: #991b1b; color: #fff; }
.toast.info    { background: var(--primary-dark); color: #fff; }
.toast.warning { background: #92400e; color: #fff; }

@keyframes toastIn {
  from { transform: translateX(100%); opacity: 0; }
  to   { transform: translateX(0);    opacity: 1; }
}

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

/* ── Print Styles (PDF export) ──────────────────────────────────── */
@media print {
  .app-header,
  .tab-nav,
  .variable-panel,
  .analysis-config,
  .data-toolbar { display: none !important; }

  .app-layout { display: block; }
  .analysis-output { overflow: visible; padding: 0; }
  .tab-pane { display: block !important; }
}