/**
 * Commerce Learning Hub - Component Styles
 * 
 * Contains: Buttons, cards, forms, modals, toasts, badges, etc.
 */

/* ============================================
   BUTTONS
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  cursor: pointer;
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn--primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}

.btn--primary:hover {
  background: var(--color-primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn--secondary {
  background: var(--color-surface);
  color: var(--color-text);
  border-color: var(--color-border);
}

.btn--secondary:hover {
  background: var(--color-surface-elevated);
  border-color: var(--color-border-strong);
}

.btn--ghost {
  background: transparent;
  color: var(--color-text-secondary);
}

.btn--ghost:hover {
  background: var(--color-surface-elevated);
  color: var(--color-text);
}

.btn--sm {
  padding: var(--space-1) var(--space-3);
  font-size: var(--text-xs);
}

.btn--lg {
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-base);
}

.btn--icon {
  width: 2.5rem;
  height: 2.5rem;
  padding: 0;
  border-radius: var(--radius-md);
}

/* ============================================
   CARDS
   ============================================ */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  transition: all var(--transition-base);
}

.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.card__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-4);
}

.card__title {
  font-size: var(--text-lg);
  font-weight: var(--font-semibold);
  color: var(--color-text);
}

.card__body {
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
}

.card__footer {
  margin-top: var(--space-4);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
  display: flex;
  gap: var(--space-2);
}

/* Glassmorphism card */
.card--glass {
  background: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-glass);
}

/* ============================================
   FORMS
   ============================================ */
.form-group {
  margin-bottom: var(--space-4);
}

.form-label {
  display: block;
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--color-text);
  margin-bottom: var(--space-2);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-sm);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

.form-input::placeholder {
  color: var(--color-text-muted);
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

.form-help {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  margin-top: var(--space-1);
}

.form-error {
  font-size: var(--text-xs);
  color: var(--color-error);
  margin-top: var(--space-1);
}

/* ============================================
   BADGES
   ============================================ */
.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--space-1) var(--space-2);
  font-size: var(--text-xs);
  font-weight: var(--font-medium);
  border-radius: var(--radius-full);
  background: var(--color-surface-elevated);
  color: var(--color-text-secondary);
}

.badge--primary {
  background: var(--color-primary-light);
  color: var(--color-primary);
}

.badge--success {
  background: rgba(16, 185, 129, 0.1);
  color: var(--color-success);
}

.badge--warning {
  background: rgba(245, 158, 11, 0.1);
  color: var(--color-warning);
}

.badge--error {
  background: rgba(239, 68, 68, 0.1);
  color: var(--color-error);
}

/* ============================================
   TOAST NOTIFICATIONS
   ============================================ */
.toast-container {
  position: fixed;
  top: calc(var(--header-height) + var(--space-4));
  right: var(--space-4);
  z-index: var(--z-toast);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  max-width: 400px;
}

.toast {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: start;
  gap: var(--space-3);
  animation: slideIn 0.3s ease;
}

.toast--success { border-left: 4px solid var(--color-success); }
.toast--error { border-left: 4px solid var(--color-error); }
.toast--warning { border-left: 4px solid var(--color-warning); }
.toast--info { border-left: 4px solid var(--color-info); }

.toast__icon {
  font-size: var(--text-xl);
  flex-shrink: 0;
}

.toast__content {
  flex: 1;
}

.toast__title {
  font-weight: var(--font-semibold);
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

.toast__message {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.toast__close {
  color: var(--color-text-muted);
  cursor: pointer;
  padding: var(--space-1);
}

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

/* ============================================
   MODAL
   ============================================ */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  z-index: var(--z-modal);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-base);
}

.modal-overlay--active {
  opacity: 1;
  pointer-events: auto;
}

.modal {
  background: var(--color-surface);
  border-radius: var(--radius-xl);
  max-width: 600px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-xl);
  transform: scale(0.95);
  transition: transform var(--transition-base);
}

.modal-overlay--active .modal {
  transform: scale(1);
}

.modal__header {
  padding: var(--space-6);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal__title {
  font-size: var(--text-xl);
  font-weight: var(--font-semibold);
}

.modal__body {
  padding: var(--space-6);
}

.modal__footer {
  padding: var(--space-4) var(--space-6);
  border-top: 1px solid var(--color-border);
  display: flex;
  justify-content: flex-end;
  gap: var(--space-2);
}

/* ============================================
   BREADCRUMBS
   ============================================ */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
}

.breadcrumbs__separator {
  color: var(--color-border-strong);
}

.breadcrumbs__link {
  color: var(--color-text-secondary);
  transition: color var(--transition-fast);
}

.breadcrumbs__link:hover {
  color: var(--color-primary);
  text-decoration: none;
}

.breadcrumbs__current {
  color: var(--color-text);
  font-weight: var(--font-medium);
}

/* ============================================
   LOADING SPINNER
   ============================================ */
.spinner {
  width: 2rem;
  height: 2rem;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

.loading-overlay {
  position: absolute;
  inset: 0;
  background: rgba(255, 255, 255, 0.8);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-base);
}

[data-theme="dark"] .loading-overlay {
  background: rgba(15, 23, 42, 0.8);
}

/* ============================================
   HERO SECTION (added in Phase 2)
   ============================================ */
.hero {
  position: relative;
  padding: var(--space-16) var(--space-8);
  border-radius: var(--radius-2xl);
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  color: var(--color-text-inverse);
  overflow: hidden;
  margin-bottom: var(--space-8);
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: 
    radial-gradient(circle at 20% 30%, rgba(255, 255, 255, 0.15) 0%, transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
  pointer-events: none;
}

.hero__content {
  position: relative;
  max-width: 720px;
  z-index: 1;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-1) var(--space-3);
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: var(--font-medium);
  margin-bottom: var(--space-4);
  backdrop-filter: blur(8px);
}

.hero__title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: var(--font-bold);
  line-height: var(--leading-tight);
  margin-bottom: var(--space-4);
  color: var(--color-text-inverse);
}

.hero__subtitle {
  font-size: var(--text-lg);
  line-height: var(--leading-relaxed);
  opacity: 0.92;
  margin-bottom: var(--space-6);
  color: var(--color-text-inverse);
}

.hero__actions {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.hero__btn {
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-md);
  font-weight: var(--font-semibold);
  font-size: var(--text-base);
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  cursor: pointer;
  border: none;
}

.hero__btn--primary {
  background: var(--color-text-inverse);
  color: var(--color-primary);
}

.hero__btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
  text-decoration: none;
}

.hero__btn--secondary {
  background: rgba(255, 255, 255, 0.15);
  color: var(--color-text-inverse);
  border: 1px solid rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(8px);
}

.hero__btn--secondary:hover {
  background: rgba(255, 255, 255, 0.25);
  text-decoration: none;
}

.hero__stats {
  display: flex;
  gap: var(--space-8);
  margin-top: var(--space-8);
  flex-wrap: wrap;
}

.hero__stat {
  display: flex;
  flex-direction: column;
}

.hero__stat-value {
  font-size: var(--text-3xl);
  font-weight: var(--font-bold);
  line-height: 1;
}

.hero__stat-label {
  font-size: var(--text-sm);
  opacity: 0.85;
  margin-top: var(--space-1);
}

@media (max-width: 768px) {
  .hero {
    padding: var(--space-10) var(--space-4);
  }
  .hero__stats {
    gap: var(--space-6);
  }
}

/* ============================================
   CATEGORY SECTION (added in Phase 2)
   ============================================ */
.category-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-4);
}

.category-card {
  padding: var(--space-6);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  text-align: center;
  transition: all var(--transition-base);
  cursor: pointer;
}

.category-card:hover {
  border-color: var(--color-primary);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  text-decoration: none;
}

.category-card__icon {
  width: 3.5rem;
  height: 3.5rem;
  margin: 0 auto var(--space-3);
  background: var(--color-primary-light);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-2xl);
  transition: transform var(--transition-base);
}

.category-card:hover .category-card__icon {
  transform: scale(1.1) rotate(-5deg);
}

.category-card__title {
  font-size: var(--text-base);
  font-weight: var(--font-semibold);
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

.category-card__count {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

@media (max-width: 1024px) {
  .category-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 480px) {
  .category-grid { grid-template-columns: 1fr; }
}

/* ============================================
   CTA SECTION (added in Phase 2)
   ============================================ */
.cta-section {
  padding: var(--space-12) var(--space-8);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-2xl);
  text-align: center;
  margin-top: var(--space-8);
  position: relative;
  overflow: hidden;
}

.cta-section::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gradient-mesh);
  opacity: 0.5;
  pointer-events: none;
}

.cta-section__content {
  position: relative;
  max-width: 600px;
  margin: 0 auto;
}

.cta-section__title {
  font-size: var(--text-3xl);
  font-weight: var(--font-bold);
  margin-bottom: var(--space-3);
}

.cta-section__text {
  font-size: var(--text-lg);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-6);
}

.cta-section__actions {
  display: flex;
  gap: var(--space-3);
  justify-content: center;
  flex-wrap: wrap;
}

/* ============================================
   SECTION HEADER (added in Phase 2)
   ============================================ */
.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: var(--space-6);
  gap: var(--space-4);
  flex-wrap: wrap;
}

.section-header__title {
  font-size: var(--text-2xl);
  font-weight: var(--font-bold);
  margin: 0;
}

.section-header__subtitle {
  color: var(--color-text-secondary);
  margin-top: var(--space-1);
  margin-bottom: 0;
}

.section-header__action {
  color: var(--color-primary);
  font-weight: var(--font-medium);
  font-size: var(--text-sm);
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
}

.section-header__action:hover {
  text-decoration: underline;
}