/* materials.css — Materials page styles */

/* Layout */
.materials-layout {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
  max-width: 1400px;
  margin: 0 auto;
}

/* Filters Bar */
.filters-bar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-lg);
  align-items: flex-end;
  padding: var(--space-lg);
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(20px);
}

.filter-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.filter-group--search {
  flex: 1;
  min-width: 200px;
}

.filter-label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  font-weight: 600;
}

/* Filter Pills */
.filter-pills {
  display: flex;
  gap: 4px;
}

.filter-pill {
  padding: 8px 14px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-pill);
  color: var(--text-muted);
  font-size: 0.85rem;
  font-family: inherit;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.filter-pill:hover {
  background: rgba(255, 255, 255, 0.1);
  color: var(--text-main);
}

.filter-pill.active {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
}

/* Filter Select */
.filter-select {
  padding: 8px 14px;
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  color: var(--text-main);
  font-size: 0.85rem;
  font-family: inherit;
  cursor: pointer;
  transition: border-color var(--transition-fast);
  min-width: 160px;
}

.filter-select:hover {
  border-color: var(--accent);
}

.filter-select:focus {
  outline: none;
  border-color: var(--accent);
}

/* Search Input */
.search-input {
  width: 100%;
  padding: 8px 14px;
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  color: var(--text-main);
  font-size: 0.9rem;
  font-family: inherit;
  transition: border-color var(--transition-fast);
}

.search-input::placeholder {
  color: var(--text-muted);
  opacity: 0.6;
}

.search-input:focus {
  outline: none;
  border-color: var(--accent);
}

/* Results Bar */
.results-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 var(--space-xs);
}

.results-count {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.btn-clear-filters {
  padding: 6px 12px;
  background: transparent;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  color: var(--text-muted);
  font-size: 0.8rem;
  font-family: inherit;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-clear-filters:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
  border-color: var(--accent);
}

/* Materials List Container */
.materials-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

/* Domain Section (Accordion) */
.domain-section {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  overflow: hidden;
  backdrop-filter: blur(20px);
}

.domain-header {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  width: 100%;
  padding: var(--space-md) var(--space-lg);
  background: transparent;
  border: none;
  color: var(--text-main);
  font-family: inherit;
  cursor: pointer;
  transition: background var(--transition-fast);
}

.domain-header:hover {
  background: rgba(255, 255, 255, 0.03);
}

.domain-chevron {
  font-size: 0.8rem;
  color: var(--text-muted);
  transition: transform var(--transition-fast);
  width: 1em;
}

.domain-section.collapsed .domain-chevron {
  transform: rotate(-90deg);
}

.domain-name {
  font-size: 1.1rem;
  font-weight: 600;
  text-transform: capitalize;
  flex: 1;
  text-align: left;
}

.domain-count {
  font-size: 0.8rem;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.06);
  padding: 3px 10px;
  border-radius: var(--radius-pill);
}

/* Domain Items Container */
.domain-items {
  padding: 0 var(--space-lg) var(--space-md);
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.domain-section.collapsed .domain-items {
  display: none;
}

/* Topic Section (Nested Accordion) */
.topic-section {
  margin-bottom: 2px;
}

.topic-section:last-child {
  margin-bottom: 0;
}

.topic-header {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  background: rgba(255, 255, 255, 0.02);
  border: none;
  border-radius: var(--radius-md);
  color: var(--text-main);
  font-family: inherit;
  cursor: pointer;
  transition: background var(--transition-fast);
}

.topic-header:hover {
  background: rgba(255, 255, 255, 0.06);
}

.topic-chevron {
  font-size: 0.7rem;
  color: var(--text-muted);
  transition: transform var(--transition-fast);
  width: 1em;
  opacity: 0.7;
}

.topic-section.collapsed .topic-chevron {
  transform: rotate(-90deg);
}

.topic-name {
  font-size: 0.9rem;
  font-weight: 500;
  flex: 1;
  text-align: left;
  color: var(--text-secondary, var(--text-main));
  opacity: 0.9;
}

.topic-count {
  font-size: 0.75rem;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.04);
  padding: 2px 8px;
  border-radius: var(--radius-pill);
  opacity: 0.8;
}

/* Topic Items Container */
.topic-items {
  padding: 2px 0 var(--space-sm) var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.topic-section.collapsed .topic-items {
  display: none;
}

/* Material Row */
.material-row {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background var(--transition-fast);
}

.material-row:hover {
  background: rgba(255, 255, 255, 0.05);
}

.material-title {
  flex: 1;
  font-size: 0.9rem;
  color: var(--text-main);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* Complexity Pills */
.complexity-pill {
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  font-size: 0.7rem;
  font-weight: 500;
  flex-shrink: 0;
}

.complexity-pill.complexity-1 {
  background: rgba(81, 207, 102, 0.15);
  color: var(--ok);
}

.complexity-pill.complexity-2 {
  background: rgba(255, 165, 0, 0.15);
  color: var(--warn);
}

.complexity-pill.complexity-3 {
  background: rgba(255, 107, 107, 0.15);
  color: var(--danger);
}

/* Copy Button */
.copy-btn {
  opacity: 0;
  padding: 4px 8px;
  background: transparent;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-size: 0.75rem;
  cursor: pointer;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.material-row:hover .copy-btn {
  opacity: 1;
}

.copy-btn:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
}

/* Empty State */
.materials-list .empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Toast Notification */
.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  padding: 12px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  color: var(--text-main);
  font-size: 0.9rem;
  backdrop-filter: blur(20px);
  opacity: 0;
  transition: all 0.3s ease;
  z-index: 1000;
  pointer-events: none;
}

.toast.show {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

.toast.success {
  border-color: var(--ok);
}

/* Responsive */
@media (max-width: 768px) {
  .filters-bar {
    flex-direction: column;
    align-items: stretch;
  }

  .filter-group {
    width: 100%;
  }

  .filter-pills {
    flex-wrap: wrap;
  }

  .filter-group--search {
    min-width: auto;
  }

  .nav-label {
    display: none;
  }

  .nav-item {
    padding: 8px 10px;
  }
}

@media (max-width: 600px) {
  .material-row {
    flex-wrap: wrap;
    gap: var(--space-sm);
  }

  .material-title {
    width: 100%;
    white-space: normal;
  }

  .copy-btn {
    opacity: 1;
  }
}