/* CSS Custom Properties for Design System */
:root {
  --primary-color: #6366f1; /* Sleek indigo */
  --primary-hover: #4f46e5;
  --bg-color: #ffffff;
  --bg-card: #ffffff;
  --bg-input: #f8fafc;
  --bg-input-focus: #ffffff;
  --bg-hover: #f1f5f9;
  --bg-active: #e2e8f0;
  --bg-empty: #fafafa;
  --text-color: #0f172a; /* Slate 900 */
  --text-muted: #64748b; /* Slate 500 */
  --text-label: #334155;
  --border-color: #e2e8f0; /* Slate 200 */
  --border-focus: #cbd5e1;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  
  /* Responsive Spacing Scale */
  --space-xs: 0.5rem;   /* 8px */
  --space-sm: 1rem;     /* 16px */
  --space-md: 1.5rem;   /* 24px */
  --space-lg: 2.5rem;   /* 40px */
  --space-xl: 4rem;     /* 64px */

  /* Typography Scale */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-size-base: 1rem;
  --font-size-lg: 1.25rem;
  --font-size-xl: 1.75rem;
  --font-size-display: 2.5rem;

  /* Max widths */
  --container-max-width: 1200px;
}

body.dark-theme {
  --bg-color: #09090b;      /* Zinc 950 - pitch/charcoal black */
  --bg-card: #18181b;       /* Zinc 900 */
  --bg-input: #18181b;      /* Zinc 900 */
  --bg-input-focus: #09090b;/* Zinc 950 */
  --bg-hover: #27272a;      /* Zinc 800 */
  --bg-active: #3f3f46;     /* Zinc 700 */
  --bg-empty: #09090b;      /* Zinc 950 */
  --text-color: #fafafa;    /* Zinc 50 */
  --text-muted: #a1a1aa;    /* Zinc 400 */
  --text-label: #e4e4e7;    /* Zinc 300 */
  --border-color: #27272a;  /* Zinc 800 */
  --border-focus: #3f3f46;  /* Zinc 700 */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.6);
}

/* Sun/Moon Toggle Icons display control based on theme */
body.dark-theme .sun-icon {
  display: block !important;
}
body.dark-theme .moon-icon {
  display: none !important;
}
body:not(.dark-theme) .sun-icon {
  display: none !important;
}
body:not(.dark-theme) .moon-icon {
  display: block !important;
}

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

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: 1.5;
  background-color: var(--bg-color);
  color: var(--text-color);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Responsive Container */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-sm);
  padding-right: var(--space-sm);
}

/* Media Queries for responsive adjustments */
@media (min-width: 640px) {
  :root {
    --font-size-display: 3rem;
    --space-sm: 1.25rem;
    --space-md: 2rem;
    --space-lg: 3.5rem;
  }
  .container {
    padding-left: var(--space-md);
    padding-right: var(--space-md);
  }
}

@media (min-width: 1024px) {
  :root {
    --font-size-display: 4rem;
    --space-sm: 1.5rem;
    --space-md: 2.5rem;
    --space-lg: 4.5rem;
  }
}

/* Header Styling */
.site-header {
  position: sticky;
  top: 0;
  background-color: var(--bg-card);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  z-index: 100;
}

/* NeuroSpark Logo with Gradient Accent */
.logo {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.025em;
  color: var(--text-color);
  user-select: none;
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon-svg {
  width: 24px;
  height: 24px;
  color: #4f46e5; /* soft indigo */
  display: block;
}

.logo-accent {
  background: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Header Actions Layout */
.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* Header Settings Gear Button */
.header-settings-btn {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 6px;
  transition: color 0.15s, background-color 0.15s;
}

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

/* Minimalist Control Row Layout (NotebookLM Style) */
.control-row {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 24px;
  margin-bottom: 24px;
}

.search-sort-group {
  display: flex;
  gap: 8px;
  flex: 1;
}

/* Search Input */
.search-wrapper {
  position: relative;
  flex: 1;
  max-width: 360px;
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: #64748b;
  pointer-events: none;
}

.search-wrapper input {
  width: 100%;
  height: 36px;
  padding: 6px 12px 6px 36px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-input);
  font-family: var(--font-sans);
  font-size: 0.875rem; /* 14px */
  color: var(--text-color);
  outline: none;
  transition: background-color 0.15s, border-color 0.15s;
}

.search-wrapper input:focus {
  background-color: var(--bg-input-focus);
  border-color: var(--border-focus);
}

/* Sort Dropdown */
.sort-wrapper {
  position: relative;
}

.sort-wrapper select {
  height: 36px;
  padding: 6px 30px 6px 12px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-input);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-label);
  outline: none;
  cursor: pointer;
  appearance: none;
  transition: background-color 0.15s, border-color 0.15s;
}

.sort-wrapper select:focus {
  background-color: var(--bg-input-focus);
  border-color: var(--border-focus);
}

/* Custom dropdown arrow */
.sort-wrapper::after {
  content: "";
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  width: 8px;
  height: 5px;
  background-color: var(--text-muted);
  clip-path: polygon(100% 0, 0 0, 50% 100%);
  pointer-events: none;
}

/* Create Button */
.create-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  height: 36px;
  padding: 6px 16px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-card);
  color: var(--text-color);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.15s, border-color 0.15s;
}

.create-btn:hover {
  background-color: var(--bg-input);
  border-color: var(--border-focus);
}

.create-btn:active {
  background-color: var(--bg-hover);
}

/* Responsive adjustments */
@media (min-width: 640px) {
  .control-row {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }
}

/* Decks Container (Supports Grid & List Views) */
.deck-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
  margin-top: 24px;
  margin-bottom: 40px;
}

.deck-grid.list-view {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* Individual Notebook/Deck Card */
.deck-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 16px;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: border-color 0.12s, background-color 0.12s;
}

.deck-card:hover {
  border-color: var(--border-focus);
  background-color: var(--bg-input);
}

.deck-card-header {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #4f46e5; /* soft indigo */
}

.deck-card-title {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-color);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.deck-card-meta {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* List View overrides for card */
.deck-grid.list-view .deck-card {
  flex-direction: row;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  gap: 16px;
}

.deck-grid.list-view .deck-card-header {
  flex: 1;
}

.deck-grid.list-view .deck-card-meta {
  text-align: right;
  display: flex;
  flex-direction: row;
  gap: 16px;
}

.deck-grid.list-view .deck-card-meta span {
  display: inline-block;
}

.deck-grid.list-view .deck-card-meta span:last-child {
  margin-top: 0 !important;
}

/* Views Management */
.view-panel {
  display: none;
}

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

/* Settings Page Styling */
.settings-header {
  margin-top: 32px;
  margin-bottom: 24px;
}

.settings-header h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-color);
  margin-bottom: 6px;
}

.settings-subtitle {
  font-size: 0.875rem;
  color: var(--text-muted);
  max-width: 600px;
}

.settings-form {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 24px;
  max-width: 600px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.form-group label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-label);
}

.form-group select,
.form-group input {
  height: 38px;
  padding: 8px 12px;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-input);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  color: var(--text-color);
  outline: none;
  transition: background-color 0.15s, border-color 0.15s;
}

.form-group select:focus,
.form-group input:focus {
  background-color: var(--bg-input-focus);
  border-color: var(--border-focus);
}

/* API Key Input Wrapper with Eye Icon */
.api-key-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.api-key-input-wrapper input {
  width: 100%;
  padding-right: 40px;
}

.btn-icon {
  position: absolute;
  right: 8px;
  background: none;
  border: none;
  cursor: pointer;
  color: #64748b;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4px;
  border-radius: 4px;
}

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

/* Settings Actions */
.settings-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 8px;
}

.save-settings-btn {
  height: 38px;
  padding: 8px 20px;
  border-radius: 6px;
  border: 1px solid var(--border-focus);
  background-color: var(--bg-hover);
  color: var(--text-color);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.15s, border-color 0.15s;
}

.save-settings-btn:hover {
  background-color: var(--bg-active);
}

.clear-settings-btn {
  height: 38px;
  padding: 8px 16px;
  border-radius: 6px;
  border: none;
  background-color: transparent;
  color: #ef4444;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
}

.clear-settings-btn:hover {
  text-decoration: underline;
}

/* App Metadata card */
.settings-info-card {
  margin-top: 32px;
  border-top: 1px solid var(--border-color);
  padding-top: 24px;
  max-width: 600px;
}

.settings-info-card h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-color);
  margin-bottom: 16px;
}

.info-row {
  display: flex;
  justify-content: space-between;
  padding: 8px 0;
  font-size: 0.875rem;
  border-bottom: 1px dashed var(--border-color);
}

.info-label {
  color: var(--text-muted);
  font-weight: 500;
}

.info-value {
  color: var(--text-label);
  font-family: monospace;
}

.api-model-input-wrapper {
  display: flex;
  gap: 8px;
}

.api-model-input-wrapper input {
  flex: 1;
}

.test-model-btn {
  height: 38px;
  padding: 8px 16px;
  border-radius: 6px;
  border: 1px solid var(--border-focus);
  background-color: var(--bg-card);
  color: var(--text-label);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.15s, border-color 0.15s;
}

.test-model-btn:hover:not(:disabled) {
  background-color: var(--bg-input);
  border-color: var(--border-focus);
}

.test-model-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* Control Row Actions & Grid/List View Toggles */
.control-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.view-toggle-group {
  display: flex;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 2px;
  background-color: var(--bg-input);
  height: 36px;
  align-items: center;
}

.toggle-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border-radius: 6px;
  border: none;
  background: none;
  color: var(--text-muted);
  cursor: pointer;
  transition: color 0.12s, background-color 0.12s;
}

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

.toggle-btn.active {
  background-color: var(--bg-card);
  color: var(--primary-color);
  box-shadow: var(--shadow-sm);
}

/* Notebook / Deck Editor View Layout (NotebookLM Style) */
.deck-editor-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 24px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 16px;
}

.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-card);
  color: var(--text-label);
  height: 32px;
  padding: 0 12px;
  border-radius: 6px;
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.12s;
}

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

.deck-editor-title-container h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-color);
}

.deck-editor-content {
  margin-top: 20px;
  width: 100%;
}

/* Notebook split editor layout */
.deck-editor-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  width: 100%;
}

@media (min-width: 768px) {
  .deck-editor-layout {
    grid-template-columns: 280px 1fr;
  }
}

.deck-sources-panel,
.deck-tools-panel {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 32px;
}

.panel-header h3 {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.add-source-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 28px;
  padding: 0 10px;
  border-radius: 6px;
  border: 1px solid var(--border-focus);
  background-color: var(--bg-card);
  color: var(--text-label);
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.12s, border-color 0.12s;
}

.add-source-btn:hover {
  background-color: var(--bg-input);
  border-color: var(--border-focus);
  color: var(--text-color);
}

.sources-list-box,
.tools-grid-box {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 24px;
  min-height: 420px;
  display: flex;
  flex-direction: column;
}

.sources-list-box.empty-sources,
.tools-grid-box.empty-tools {
  justify-content: center;
  align-items: center;
  border-style: dashed;
  border-color: var(--border-focus);
  background-color: var(--bg-empty);
}

.panel-empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  text-align: center;
}

.panel-empty-state p {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-muted);
}

.empty-icon {
  color: var(--border-focus);
}

/* WebGPU status badge styling */
.status-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8125rem;
  font-weight: 500;
  padding: 10px 14px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  width: 100%;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  display: inline-block;
  flex-shrink: 0;
}

.status-checking {
  background-color: var(--bg-input);
  border-color: var(--border-color);
  color: var(--text-muted);
}

.status-checking .status-dot {
  background-color: var(--text-muted);
  animation: badge-pulse 1.5s infinite ease-in-out;
}

.status-supported {
  background-color: rgba(34, 197, 94, 0.1);
  border-color: rgba(34, 197, 94, 0.3);
  color: #22c55e;
}

.status-supported .status-dot {
  background-color: #22c55e;
}

.status-unsupported {
  background-color: rgba(239, 68, 68, 0.1);
  border-color: rgba(239, 68, 68, 0.3);
  color: #ef4444;
}

.status-unsupported .status-dot {
  background-color: #ef4444;
}

@keyframes badge-pulse {
  0% { opacity: 0.5; transform: scale(0.95); }
  50% { opacity: 1; transform: scale(1.05); }
  100% { opacity: 0.5; transform: scale(0.95); }
}

/* Local directory picker layout */
.directory-input-wrapper {
  display: flex;
  gap: 8px;
}

.directory-input-wrapper input {
  flex: 1;
}

.select-dir-btn {
  height: 38px;
  padding: 8px 16px;
  border-radius: 6px;
  border: 1px solid var(--border-focus);
  background-color: var(--bg-card);
  color: var(--text-label);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: background-color 0.15s, border-color 0.15s;
}

.select-dir-btn:hover {
  background-color: var(--bg-input);
  border-color: var(--border-focus);
}

.select-dir-btn svg {
  color: var(--text-muted);
}

/* Editable notebook title input */
.deck-title-input {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-color);
  border: none;
  background: transparent;
  padding: 4px 8px;
  border-radius: 6px;
  width: 100%;
  max-width: 480px;
  font-family: var(--font-sans);
  outline: none;
  transition: background-color 0.12s, box-shadow 0.12s;
}

.deck-title-input:hover {
  background-color: var(--bg-hover);
}

.deck-title-input:focus {
  background-color: var(--bg-input-focus);
  box-shadow: 0 0 0 2px var(--border-color);
}

/* Source list item styles */
.source-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 12px;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.8125rem;
  color: var(--text-label);
  transition: background-color 0.12s;
}

.source-item:hover {
  background-color: var(--bg-input);
}

.source-item:last-child {
  border-bottom: none;
}

.source-item-info {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1;
  min-width: 0;
}

.source-icon {
  color: #6366f1;
  flex-shrink: 0;
}

.source-name {
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 160px;
}

.source-size {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.delete-source-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4px;
  border-radius: 4px;
  transition: color 0.12s, background-color 0.12s;
}

.delete-source-btn:hover {
  color: #ef4444;
  background-color: rgba(239, 68, 68, 0.1);
}

/* Embedding & LLM download styles */
.model-select-download-wrapper {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  width: 100%;
}

.model-select-download-wrapper select {
  flex: 1 1 240px;
  min-width: 0;
}

.download-model-btn {
  height: 38px;
  padding: 8px 16px;
  border-radius: 6px;
  border: 1px solid #6366f1;
  background-color: #6366f1;
  color: #ffffff;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: background-color 0.15s, border-color 0.15s;
  flex: 1 1 auto;
  min-width: 120px;
}

.download-model-btn:hover {
  background-color: #4f46e5;
  border-color: #4f46e5;
}

/* Download progress widget styling */
.download-progress-container {
  background-color: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.progress-header {
  display: flex;
  justify-content: space-between;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-label);
}

.progress-bar-bg {
  height: 6px;
  background-color: var(--border-color);
  border-radius: 3px;
  overflow: hidden;
  width: 100%;
}

.progress-bar-fill {
  height: 100%;
  background-color: #6366f1;
  width: 0%;
  transition: width 0.1s linear;
}

.progress-details {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-muted);
  font-family: monospace;
}

/* Tools Grid Layout & Premium Cards */
.tools-grid-container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 16px;
  width: 100%;
}

.tool-card {
  background-color: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 16px;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: border-color 0.15s ease, transform 0.15s ease, box-shadow 0.15s ease;
}

.tool-card:hover {
  border-color: var(--primary-color);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.tool-card-icon {
  color: var(--primary-color);
  display: flex;
  width: 24px;
  height: 24px;
}

.tool-card-title {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-color);
}

.tool-card-description {
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.4;
}