/* ==========================================================================
   DailyBook UI Components
   Buttons, Cards, Inputs, Toasts, Skeletons, Modals, Reading Typography
   ========================================================================== */

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  line-height: 1.25;
  padding: 10px 18px;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  white-space: nowrap;
  transition: all var(--transition-fast);
  user-select: none;
}

.btn:disabled, .btn.disabled {
  opacity: 0.6;
  cursor: not-allowed;
  pointer-events: none;
}

.btn-primary {
  background-color: var(--accent);
  color: #FFFFFF;
  border-color: var(--accent);
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--accent-hover);
  border-color: var(--accent-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

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

.btn-secondary:hover:not(:disabled) {
  background-color: var(--bg-tertiary);
  border-color: var(--border-dark);
}

.btn-outline {
  background-color: transparent;
  color: var(--text-primary);
  border-color: var(--border-color);
}

.btn-outline:hover:not(:disabled) {
  background-color: var(--bg-secondary);
  border-color: var(--border-dark);
}

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

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

.btn-danger {
  background-color: var(--danger);
  color: #FFFFFF;
  border-color: var(--danger);
}

.btn-danger:hover:not(:disabled) {
  background-color: var(--danger-hover);
  border-color: var(--danger-hover);
}

.btn-danger-outline {
  background-color: transparent;
  color: var(--danger);
  border-color: var(--danger-border);
}

.btn-danger-outline:hover:not(:disabled) {
  background-color: var(--danger-light);
}

.btn-sm {
  padding: 6px 12px;
  font-size: 0.8125rem;
  border-radius: var(--radius-sm);
}

.btn-lg {
  padding: 14px 24px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-md);
}

.btn-icon {
  padding: 8px;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
}

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

/* Spinner inside button */
.btn-spinner {
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: currentColor;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

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

/* ==========================================================================
   Form Controls
   ========================================================================== */
.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 20px;
}

.form-label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-primary);
}

.form-input, .form-textarea, .form-select {
  width: 100%;
  padding: 10px 14px;
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  color: var(--text-primary);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  outline: none;
  transition: all var(--transition-fast);
}

.form-input:focus, .form-textarea:focus, .form-select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-subtle);
}

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

.form-input.is-invalid, .form-textarea.is-invalid {
  border-color: var(--danger);
  box-shadow: 0 0 0 3px var(--danger-light);
}

.form-textarea {
  min-height: 140px;
  resize: vertical;
  line-height: 1.6;
}

.form-hint {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

.form-error {
  font-size: 0.8125rem;
  color: var(--danger);
  display: flex;
  align-items: center;
  gap: 4px;
}

/* Password Toggle Wrapper */
.input-with-toggle {
  position: relative;
  display: flex;
  align-items: center;
}

.input-with-toggle .form-input {
  padding-right: 42px;
}

.input-toggle-btn {
  position: absolute;
  right: 12px;
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px;
  display: flex;
  align-items: center;
}

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

/* ==========================================================================
   Badges & Tags
   ========================================================================== */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 3px 8px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 500;
  line-height: 1;
}

.badge-public {
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
}

.badge-followers {
  background-color: var(--accent-subtle);
  color: var(--accent);
  border: 1px solid var(--accent-border);
}

.badge-private {
  background-color: var(--warning-light);
  color: var(--warning);
  border: 1px solid var(--warning-border);
}

.tag-pill {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 500;
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.tag-pill:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

/* ==========================================================================
   User Avatar
   ========================================================================== */
.avatar {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 0.875rem;
  color: #FFFFFF;
  background-color: var(--accent);
  user-select: none;
  flex-shrink: 0;
  text-transform: uppercase;
}

.avatar-sm {
  width: 28px;
  height: 28px;
  font-size: 0.75rem;
}

.avatar-lg {
  width: 52px;
  height: 52px;
  font-size: 1.25rem;
}

.avatar-xl {
  width: 80px;
  height: 80px;
  font-size: 2rem;
}

/* Deterministic Avatar Pastel Tints */
.avatar-tint-0 { background: linear-gradient(135deg, #3B82F6, #1D4ED8); }
.avatar-tint-1 { background: linear-gradient(135deg, #8B5CF6, #6D28D9); }
.avatar-tint-2 { background: linear-gradient(135deg, #EC4899, #BE185D); }
.avatar-tint-3 { background: linear-gradient(135deg, #10B981, #047857); }
.avatar-tint-4 { background: linear-gradient(135deg, #F59E0B, #B45309); }
.avatar-tint-5 { background: linear-gradient(135deg, #06B6D4, #0E7490); }
.avatar-tint-6 { background: linear-gradient(135deg, #6366F1, #4338CA); }
.avatar-tint-7 { background: linear-gradient(135deg, #64748B, #334155); }

/* ==========================================================================
   Article / Post Cards
   ========================================================================== */
.post-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 20px;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), border-color var(--transition-normal);
  display: flex;
  flex-direction: column;
  gap: 14px;
  position: relative;
}

.post-card:hover {
  transform: translateY(-2px);
  border-color: var(--border-dark);
  box-shadow: var(--shadow-md);
}

.post-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.post-author-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.post-author-name {
  font-weight: 600;
  font-size: 0.9375rem;
  color: var(--text-primary);
}

.post-author-name:hover {
  color: var(--accent);
}

.post-meta-sub {
  font-size: 0.8125rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 6px;
}

.post-dot-sep {
  opacity: 0.6;
}

.post-card-title {
  font-size: 1.35rem;
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.015em;
  color: var(--text-primary);
  margin-top: 2px;
}

.post-card-title a:hover {
  color: var(--accent);
}

.post-card-excerpt {
  font-size: 0.9375rem;
  line-height: 1.6;
  color: var(--text-secondary);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.post-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-top: 8px;
  border-top: 1px solid var(--border-light);
  margin-top: auto;
}

.post-tags-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.post-read-more {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--accent);
  transition: transform var(--transition-fast);
}

.post-card:hover .post-read-more {
  transform: translateX(3px);
}

/* ==========================================================================
   Editorial Reading Mode (post.html)
   ========================================================================== */
.article-header {
  margin-bottom: 36px;
}

.article-title {
  font-family: var(--font-sans);
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.025em;
  color: var(--text-primary);
  margin-bottom: 20px;
}

.article-meta-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 0;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.article-author-cluster {
  display: flex;
  align-items: center;
  gap: 14px;
}

.article-content {
  font-family: var(--font-serif);
  font-size: 1.1875rem;
  line-height: 1.8;
  color: var(--text-primary);
  word-break: break-word;
}

.article-content p {
  margin-bottom: 24px;
}

.article-content h1, 
.article-content h2, 
.article-content h3, 
.article-content h4 {
  font-family: var(--font-sans);
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-primary);
  margin-top: 36px;
  margin-bottom: 16px;
}

.article-content h1 { font-size: 1.85rem; }
.article-content h2 { font-size: 1.5rem; }
.article-content h3 { font-size: 1.25rem; }

.article-content blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 20px;
  margin: 28px 0;
  font-style: italic;
  color: var(--text-secondary);
}

.article-content ul, .article-content ol {
  margin: 20px 0 24px 28px;
}

.article-content li {
  margin-bottom: 8px;
}

.article-content pre {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.9375rem;
  line-height: 1.6;
  margin: 28px 0;
}

.article-content code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--bg-secondary);
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid var(--border-color);
}

.article-content pre code {
  background: transparent;
  padding: 0;
  border: none;
}

.article-content a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ==========================================================================
   Tabs
   ========================================================================== */
.tabs-nav {
  display: flex;
  align-items: center;
  gap: 8px;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 24px;
}

.tab-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  margin-bottom: -1px;
}

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

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

.tab-count {
  font-size: 0.75rem;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background: var(--bg-secondary);
  color: var(--text-secondary);
}

.tab-btn.active .tab-count {
  background: var(--accent-subtle);
  color: var(--accent);
}

/* ==========================================================================
   Visibility Selector Cards (Create Post)
   ========================================================================== */
.visibility-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.visibility-card {
  border: 1.5px solid var(--border-color);
  background: var(--bg-surface);
  border-radius: var(--radius-md);
  padding: 14px 16px;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  flex-direction: column;
  gap: 4px;
  user-select: none;
}

.visibility-card:hover {
  border-color: var(--border-dark);
  background: var(--bg-secondary);
}

.visibility-card.selected {
  border-color: var(--accent);
  background: var(--accent-subtle);
}

.visibility-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 0.9375rem;
  color: var(--text-primary);
}

.visibility-desc {
  font-size: 0.8125rem;
  color: var(--text-muted);
  line-height: 1.4;
}

/* ==========================================================================
   Skeletons
   ========================================================================== */
.skeleton {
  background: linear-gradient(90deg, var(--bg-secondary) 25%, var(--bg-tertiary) 50%, var(--bg-secondary) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: var(--radius-sm);
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.skeleton-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 20px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.skeleton-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
}

.skeleton-title {
  height: 24px;
  width: 75%;
}

.skeleton-text {
  height: 14px;
  width: 100%;
}

.skeleton-text-short {
  height: 14px;
  width: 45%;
}

/* ==========================================================================
   Toasts (Notification System)
   ========================================================================== */
.toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 1000;
  display: flex;
  flex-direction: column;
  gap: 10px;
  pointer-events: none;
}

.toast {
  pointer-events: auto;
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  padding: 12px 18px;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  font-size: 0.9375rem;
  min-width: 280px;
  max-width: 420px;
  animation: slideUp 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  transition: opacity 0.2s ease, transform 0.2s ease;
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

.toast-icon {
  flex-shrink: 0;
}
.toast-success .toast-icon { color: var(--success); }
.toast-error .toast-icon { color: var(--danger); }
.toast-warning .toast-icon { color: var(--warning); }
.toast-info .toast-icon { color: var(--accent); }

.toast-content {
  flex: 1;
}

.toast-close {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 2px;
  display: flex;
}
.toast-close:hover { color: var(--text-primary); }

/* ==========================================================================
   Modals
   ========================================================================== */
.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(4px);
  z-index: 500;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
}

.modal-backdrop.open {
  opacity: 1;
  pointer-events: auto;
}

.modal-box {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 480px;
  padding: 28px;
  box-shadow: var(--shadow-xl);
  transform: scale(0.95);
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.modal-backdrop.open .modal-box {
  transform: scale(1);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

.modal-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.modal-body {
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.6;
  margin-bottom: 24px;
}

.modal-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
}

/* ==========================================================================
   Empty States
   ========================================================================== */
.empty-state {
  text-align: center;
  padding: 64px 24px;
  background: var(--bg-surface);
  border: 1px dashed var(--border-color);
  border-radius: var(--radius-lg);
  margin: 20px 0;
}

.empty-state-icon {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--bg-secondary);
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.empty-state-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.empty-state-desc {
  font-size: 0.9375rem;
  color: var(--text-muted);
  max-width: 420px;
  margin: 0 auto 20px;
}

/* ==========================================================================
   Pagination
   ========================================================================== */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: 36px;
}

.page-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 38px;
  height: 38px;
  padding: 0 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-surface);
  color: var(--text-primary);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.page-btn:hover:not(:disabled) {
  border-color: var(--accent);
  color: var(--accent);
}

.page-btn.active {
  background: var(--accent);
  color: #FFFFFF;
  border-color: var(--accent);
}

.page-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ==========================================================================
   Dropdowns
   ========================================================================== */
.dropdown {
  position: relative;
}

.dropdown-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  min-width: 200px;
  padding: 6px;
  z-index: 120;
  display: none;
  flex-direction: column;
  gap: 2px;
}

.dropdown-menu.show {
  display: flex;
}

.dropdown-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  color: var(--text-primary);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.dropdown-item:hover {
  background-color: var(--bg-secondary);
}

.dropdown-divider {
  height: 1px;
  background: var(--border-color);
  margin: 4px 0;
}