/* ===== Guide Card ===== */
.guide-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  box-shadow: var(--shadow-sm);
  transition:
    transform var(--transition),
    box-shadow var(--transition),
    border-color var(--transition);
}
.guide-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-primary);
  text-decoration: none;
}
.guide-card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}
.guide-card-chapter {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--color-text-muted);
}
.guide-card-tag {
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.18rem 0.55rem;
  border-radius: 999px;
  border: 1px solid var(--color-border);
  background: transparent;
  color: var(--color-primary);
  cursor: pointer;
  transition:
    background var(--transition),
    color var(--transition),
    border-color var(--transition);
  line-height: 1.4;
}
.guide-card-tag:hover,
.guide-card-tag.active {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}
.guide-card h3 {
  font-size: 1rem;
  line-height: 1.4;
  color: var(--color-text);
}
.guide-card p {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin: 0;
  flex: 1;
}
.guide-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: auto;
  padding-top: 0.75rem;
  border-top: 1px solid var(--color-border);
}
.guide-card-meta {
  display: flex;
  gap: 0.6rem;
  align-items: center;
}
.difficulty-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  flex-shrink: 0;
}
.dot-beginner {
  background: #22c55e;
}
.dot-intermediate {
  background: #f59e0b;
}
.dot-advanced {
  background: #ef4444;
}
.read-time {
  font-size: 0.78rem;
  color: var(--color-text-muted);
}
.guide-card-arrow {
  color: var(--color-primary);
  font-size: 1rem;
}

/* ===== Callout Boxes ===== */
.callout {
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
  border-left: 4px solid;
  display: flex;
  gap: 0.75rem;
}
.callout-icon {
  font-size: 1.1rem;
  flex-shrink: 0;
  margin-top: 0.1rem;
}
.callout-body {
  flex: 1;
}
.callout-body p:last-child {
  margin-bottom: 0;
}
.callout-body strong {
  display: block;
  margin-bottom: 0.25rem;
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.callout.tip {
  background: #f0fdf4;
  border-color: #22c55e;
  color: #166534;
}
.callout.note {
  background: #eff6ff;
  border-color: #3b82f6;
  color: #1e40af;
}
.callout.warn {
  background: #fffbeb;
  border-color: #f59e0b;
  color: #92400e;
}
.callout.danger {
  background: #fef2f2;
  border-color: #ef4444;
  color: #991b1b;
}

/* ===== Code Blocks ===== */
.code-block {
  background: #0f172a;
  border-radius: var(--radius-md);
  border: 1px solid #1e293b;
  margin: 1.5rem 0;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.code-block-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.6rem 1rem;
  background: rgba(255, 255, 255, 0.04);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.code-lang {
  font-size: 0.75rem;
  font-weight: 600;
  color: #64748b;
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.copy-btn {
  background: rgba(255, 255, 255, 0.08);
  border: none;
  color: #94a3b8;
  font-size: 0.75rem;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-family: var(--font-body);
  transition:
    background var(--transition),
    color var(--transition);
}
.copy-btn:hover {
  background: rgba(255, 255, 255, 0.14);
  color: #e2e8f0;
}
.copy-btn.copied {
  color: #22c55e;
}
.code-block pre {
  margin: 0;
  padding: 1.25rem;
  overflow-x: auto;
}
.code-block code {
  background: none !important;
  padding: 0 !important;
  border: none;
  border-radius: 0;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  line-height: 1.65;
  color: #e2e8f0;
}

/* ===== Table ===== */
.table-wrap {
  overflow-x: auto;
  margin: 1.5rem 0;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}
thead th {
  background: #f3f4f6;
  color: var(--color-text);
  font-weight: 600;
  text-align: left;
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--color-border);
  white-space: nowrap;
}
tbody td {
  padding: 0.7rem 1rem;
  border-bottom: 1px solid var(--color-border);
  vertical-align: top;
}
tbody tr:last-child td {
  border-bottom: none;
}
tbody tr:hover td {
  background: #f9fafb;
}

/* ===== SVG Diagram ===== */
.diagram-svg {
  margin: 1.75rem auto;
  max-width: 860px;
}
.diagram-svg svg {
  display: block;
  width: 100%;
  height: auto;
}

/* ===== Responsive ===== */
@media (max-width: 640px) {
  .code-block-header {
    flex-wrap: wrap;
    gap: 0.35rem;
    padding: 0.5rem 0.75rem;
  }
  .table-wrap {
    font-size: 0.8rem;
  }
}

/* ===== Scroll-to-top button ===== */
.scroll-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 2.5rem;
  height: 2.5rem;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: none;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition:
    opacity 0.2s,
    box-shadow var(--transition),
    transform var(--transition);
  z-index: 100;
  box-shadow: var(--shadow-md);
  color: var(--color-text-muted);
}
.scroll-top.visible {
  opacity: 1;
  pointer-events: auto;
}
.scroll-top:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
  color: var(--color-primary);
}

/* ===== Footer Newsletter ===== */
.footer-newsletter {
  margin-bottom: 0.75rem;
}
.footer-newsletter-label {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin: 0 0 0.5rem;
}
.footer-newsletter-row {
  display: flex;
  gap: 0;
  max-width: min(380px, 100%);
  margin: 0 auto;
  background: var(--color-surface);
  border: 1.5px solid var(--color-border-strong);
  border-radius: var(--radius-pill);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition:
    border-color var(--transition),
    box-shadow var(--transition);
}
.footer-newsletter-row:focus-within {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}
.footer-newsletter-row input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  padding: 0.55rem 1.1rem;
  font-size: 0.875rem;
  color: var(--color-text);
  font-family: var(--font-body);
}
.footer-newsletter-row button {
  background: var(--color-primary);
  color: #fff;
  border: none;
  padding: 0.55rem 1.25rem;
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  cursor: pointer;
  font-family: var(--font-body);
  white-space: nowrap;
  transition: background var(--transition);
  margin: 3px;
}
.footer-newsletter-row button:hover {
  background: #2456b8;
}
.footer-newsletter-row button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}
.footer-newsletter-msg {
  font-size: 0.78rem;
  margin-top: 0.5rem;
  min-height: 1.2em;
}
.footer-newsletter-msg.ok {
  color: #166534;
}
.footer-newsletter-msg.err {
  color: #991b1b;
}

/* ===== Feedback Tab ===== */
.feedback-tab {
  display: block;
  position: fixed;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  writing-mode: vertical-rl;
  text-orientation: mixed;
  background: var(--color-primary);
  color: #fff;
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  padding: 1rem 0.55rem;
  border-radius: var(--radius-sm) 0 0 var(--radius-sm);
  box-shadow: var(--shadow-md);
  z-index: 48;
  transition:
    background var(--transition),
    transform var(--transition),
    box-shadow var(--transition);
}
.feedback-tab:hover {
  background: #2456b8;
  transform: translateY(-50%) translateX(-3px);
  box-shadow: var(--shadow-lg);
  text-decoration: none;
}
@media (max-width: 767px) {
  .feedback-tab {
    font-size: 0.55rem;
    padding: 0.6rem 0.4rem;
  }
}
@media (max-width: 480px) {
  .feedback-tab {
    font-size: 0.55rem;
    padding: 0.6rem 0.4rem;
  }
  .notes-panel-toggle {
    right: 1rem;
    bottom: 4.5rem;
  }
  .scroll-top {
    right: 1rem;
    bottom: 1.25rem;
  }
}

/* ===== Text Highlight Mark ===== */
mark.text-highlight {
  background: #bfdbfe;
  color: #1e3a5f;
  cursor: pointer;
  padding: 0 2px;
  border-radius: 2px;
  transition: background 0.1s;
}
mark.text-highlight:hover {
  background: #93c5fd;
}

/* ===== Selection Tooltip ===== */
.hl-tooltip {
  position: fixed;
  z-index: 9100;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  font-family: var(--font-body);
  font-size: 0.75rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.12s;
  min-width: 180px;
  max-width: min(340px, 90vw);
  overflow: hidden;
}
.hl-tooltip.visible {
  opacity: 1;
  pointer-events: auto;
}
.hl-tooltip-actions {
  display: flex;
  align-items: center;
  padding: 0.35rem 0.5rem;
  gap: 0.25rem;
  border-bottom: 1px solid var(--color-border);
  background: #f9fafb;
}
.hl-btn {
  font-family: var(--font-body);
  font-size: 0.72rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 0.35rem 0.65rem;
  transition:
    background var(--transition),
    color var(--transition);
  background: transparent;
  color: var(--color-text-muted);
}
.hl-btn:hover {
  background: var(--color-bg);
  color: var(--color-text);
}
.hl-btn-highlight {
  color: #fff;
  background: var(--color-primary);
}
.hl-btn-highlight:hover {
  background: #2456b8;
  color: #fff;
}
.hl-btn-note {
  color: var(--color-text);
}
.hl-btn-translate {
  color: var(--color-text);
}
.hl-close {
  font-family: var(--font-body);
  font-size: 0.8rem;
  border: none;
  background: transparent;
  cursor: pointer;
  padding: 0.3rem 0.4rem;
  color: var(--color-text-muted);
  border-radius: var(--radius-sm);
  margin-left: auto;
  line-height: 1;
  transition:
    background var(--transition),
    color var(--transition);
}
.hl-close:hover {
  background: var(--color-bg);
  color: var(--color-text);
}
.hl-tooltip-expand {
  display: none;
  flex-direction: column;
  gap: 0.5rem;
  padding: 0.75rem;
  border-top: 1px solid var(--color-border);
}
.hl-textarea {
  font-family: var(--font-body);
  font-size: 0.8rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 0.5rem 0.6rem;
  resize: vertical;
  width: 100%;
  box-sizing: border-box;
  outline: none;
  min-height: 64px;
  color: var(--color-text);
  background: var(--color-surface);
  transition:
    border-color var(--transition),
    box-shadow var(--transition);
}
.hl-textarea:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}
.hl-expand-actions {
  display: flex;
  gap: 0.5rem;
}
.hl-btn-save {
  background: var(--color-primary);
  color: #fff;
}
.hl-btn-save:hover {
  background: #2456b8;
  color: #fff;
}
.hl-btn-cancel {
  color: var(--color-text-muted);
}
.hl-btn-cancel:hover {
  color: var(--color-text);
  background: var(--color-bg);
}
.hl-btn-ai {
  padding: 0.3rem 0.4rem;
}
.hl-btn-ai:hover {
  background: var(--color-bg);
}

/* Translate panel */
.hl-tooltip-translate-panel {
  display: none;
  flex-direction: column;
  gap: 0.5rem;
  padding: 0.75rem;
  border-top: 1px solid var(--color-border);
}
.hl-translate-controls {
  display: flex;
  gap: 0.4rem;
  align-items: center;
}
.hl-lang-select {
  font-family: var(--font-body);
  font-size: 0.75rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  padding: 0.3rem 0.4rem;
  flex: 1;
  cursor: pointer;
  outline: none;
  color: var(--color-text);
}
.hl-lang-select:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}
.hl-btn-do-translate {
  background: var(--color-primary);
  color: #fff;
  white-space: nowrap;
}
.hl-btn-do-translate:hover {
  background: #2456b8;
  color: #fff;
}
.hl-btn-do-translate:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}
.hl-translate-result {
  font-size: 0.8rem;
  line-height: 1.5;
  color: var(--color-text);
  min-height: 0;
  word-break: break-word;
}
.hl-translate-result:not(:empty) {
  padding: 0.5rem 0.6rem;
  background: var(--color-primary-light);
  border-left: 3px solid var(--color-primary);
  border-radius: var(--radius-sm);
}
.hl-translate-loading {
  color: var(--color-text-muted);
  font-style: italic;
}
.hl-translate-error {
  color: #991b1b;
}