/* ============================================================
   LEARNING DASHBOARD LAYOUT & RESPONSIVE PANELS
   ============================================================ */

.reading-progress-container {
  position: fixed;
  top: 60px;
  left: 0;
  width: 100%;
  height: 3px;
  background: transparent;
  z-index: 10001;
  pointer-events: none;
}

.reading-progress-bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-hover));
  box-shadow: 0 0 8px rgba(59, 130, 246, 0.5);
  transition: width 0.1s ease-out;
}

.learning-container {
  margin-top: 60px;
  min-height: calc(100vh - 60px);
  display: grid;
  grid-template-columns: 320px 1fr;
  position: relative;
  background: transparent;
}

/* ============================================================
   SIDEBAR & SEARCH STYLING
   ============================================================ */

.learning-sidebar {
  background: rgba(17, 19, 21, 0.72);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-right: 1px solid var(--border);
  height: calc(100vh - 60px);
  position: sticky;
  top: 60px;
  display: flex;
  flex-direction: column;
  z-index: 100;
  transition: transform 0.3s var(--ease);
  /* FIX: No overflow:hidden here — it was clipping active highlight borders */
}

body.light-mode .learning-sidebar {
  background: rgba(255, 255, 255, 0.85);
}

.sidebar-header {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border);
  position: relative;
  z-index: 2;
}

.sidebar-search {
  position: relative;
  width: 100%;
}

/* FIX Bug 2: Search bar overlap — icon moved to LEFT, input has left padding */
.sidebar-search input {
  width: 100%;
  padding: 0.65rem 2.5rem 0.65rem 2.5rem; /* left padding makes room for icon */
  border-radius: 20px;
  border: 1px solid var(--border);
  background: rgba(11, 13, 15, 0.6);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.85rem;
  outline: none;
  transition: var(--t);
}
:root[data-theme="sepia"] .sidebar-search input {
  background: var(--bg-surface);
}

.sidebar-search input:focus {
  border-color: var(--border-accent);
  box-shadow: 0 0 0 2px var(--accent-dim);
}

/* FIX: Icon on LEFT side so it doesn't overlap placeholder text */
.sidebar-search .search-icon {
  position: absolute;
  left: 1rem; /* moved from right to left */
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 0.85rem;
  pointer-events: none;
}

.sidebar-search .clear-btn {
  position: absolute;
  right: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-size: 1.2rem;
  cursor: pointer;
  display: none;
}

.sidebar-search .clear-btn:hover {
  color: var(--text-primary);
}

.search-results-info {
  margin-top: 0.75rem;
  font-size: 0.78rem;
  color: var(--text-muted);
  min-height: 18px;
}

/* Sidebar Tree Structure */
.sidebar-tree {
  flex: 1;
  overflow-y: auto;
  overflow-x: visible;
  padding: 0.75rem 1rem 1.5rem 1rem;
}

.sidebar-loading {
  text-align: center;
  padding: 2rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.category-group {
  margin-bottom: 1.25rem;
  margin-top: 0;
  padding-top: 4px;
}

.category-group:first-child {
  padding-top: 6px;
  margin-top: 2px;
}

.category-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 0.75rem 1rem;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  border-radius: var(--radius-md);
  text-align: left;
  transition: var(--t);
}

.category-header:hover {
  background: var(--bg-surface);
  color: var(--accent-hover);
}

.category-title {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.category-title i {
  color: var(--accent);
  width: 16px;
  text-align: center;
}

.category-arrow {
  font-size: 0.75rem;
  color: var(--text-muted);
  transition: transform 0.25s ease;
}

.category-group.collapsed .category-arrow {
  transform: rotate(-90deg);
}

.topic-list {
  list-style: none;
  margin-top: 0.25rem;
  padding-top: 0.45rem; /* extra top spacing to keep first active highlight fully visible */
  padding-left: 1rem;
  padding-bottom: 6px; /* FIX: breathing room so last item highlight isn't clipped */
  max-height: 2000px;
  overflow-x: visible; /* FIX: left border highlight must not be clipped */
  overflow-y: hidden; /* FIX: keep this for collapse animation to work */
  transition:
    max-height 0.4s ease-in-out,
    opacity 0.2s ease;
  opacity: 1;
}

.category-group.collapsed .topic-list {
  max-height: 0;
  opacity: 0;
  margin-top: 0;
}

.topic-item a {
  display: flex;
align-items: center;
  padding: 0.45rem 1rem;
  color: var(--text-secondary);
   /* color: var(--text-primary); */
  font-size: 0.825rem;
  text-decoration: none;
  border-radius: var(--radius-sm);
  border-left: 2px solid transparent;
  margin-bottom: 2px;
  margin-left: 2px; /* FIX: slight offset so border renders inside visible area */
  transition: var(--t);
  scroll-margin-top: 1.25rem; /* keep active topic fully visible when scrolled into view */
}

:root[data-theme="sepia"] .topic-item:not(.active):not(.completed) a {
  color: var(--text-primary);
}

.topic-item a:hover {
  background: var(--accent-dim);
  color: var(--text-primary);
  padding-left: 1.25rem;
}

.topic-item.active a {
  background: var(--accent-dim);
  color: var(--accent);
  font-weight: 600;
  border-left: 2px solid var(--accent);
  padding-left: 1.25rem;
  margin-left: 3px; /* FIX: reset margin so border is fully visible */
  margin-top: 2px;
  margin-bottom: 2px;
  position: relative;
  z-index: 1;
}

body.light-mode .topic-item.active a {
  background: rgba(37, 99, 235, 0.08);
  color: var(--accent);
}

/* FIX: last item in list gets extra bottom margin so highlight isn't clipped */
.topic-list li:last-child a {
  margin-bottom: 4px;
}

.progress-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin-bottom: 1rem;
}
.progress-stat-card {
  padding: 0.9rem 0.75rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  text-align: center;
  min-height: 85px;

  display: flex;
  flex-direction: column;
  justify-content: center;
}

.progress-stat-card:hover {
  transform: translateY(-2px);

  border-color: var(--border-accent);
}

/* ============================================================
   CONTENT VIEWPORT & TYPOGRAPHY
   ============================================================ */

.learning-content {
  padding: 2.5rem 3rem 4rem;
  max-width: 1000px;
  margin: 0 auto;
  width: 100%;
  display: flex;
  flex-direction: column;
}

.sidebar-toggle-btn {
  display: none;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  border-radius: 30px;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  margin-bottom: 1.5rem;
  align-self: flex-start;
  transition: var(--t);
}

.sidebar-toggle-btn:hover {
  background: var(--bg-surface);
  border-color: var(--border-hover);
}

.content-viewport {
  flex: 1;
}

.loading-article {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 300px;
  color: var(--text-muted);
  gap: 1rem;
}

.loading-article i {
  font-size: 2rem;
  color: var(--accent);
}

/* ==========================================
   SKELETON LOADER
   ========================================== */

.skeleton-loader {
  animation: fadeIn 0.2s ease;
}

.skeleton-line,
.skeleton-title,
.skeleton-meta {
  position: relative;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.06);
  border-radius: 10px;
}

body.light-mode .skeleton-line,
body.light-mode .skeleton-title,
body.light-mode .skeleton-meta {
  background: rgba(0, 0, 0, 0.08);
}

.skeleton-title {
  height: 42px;
  width: 60%;
  margin-bottom: 1rem;
}

.skeleton-meta {
  height: 18px;
  width: 220px;
  margin-bottom: 2rem;
}

.skeleton-line {
  height: 14px;
  width: 100%;
  margin-bottom: 14px;
}

.skeleton-line.short {
  width: 70%;
}

.skeleton-line.medium {
  width: 85%;
}

.skeleton-title::after,
.skeleton-meta::after,
.skeleton-line::after {
  content: "";
  position: absolute;
  inset: 0;
  transform: translateX(-100%);
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.12),
    transparent
  );
  animation: skeletonShimmer 1.4s infinite;
}

@keyframes skeletonShimmer {
  100% {
    transform: translateX(100%);
  }
}

.rendered-markdown {
  animation: fadeIn 0.4s var(--ease) forwards;
}

.rendered-markdown h1 {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}

.topic-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}

.meta-badge {
  background: var(--accent-dim);
  color: var(--accent);
  padding: 0.25rem 0.65rem;
  border-radius: 20px;
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.7rem;
  letter-spacing: 0.05em;
}

.rendered-markdown h2 {
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.35rem;
}

.rendered-markdown h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}

.rendered-markdown p {
  margin-bottom: 1.25rem;
  color: var(--text-secondary);
  line-height: 1.75;
}

.rendered-markdown ul,
.rendered-markdown ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}

.rendered-markdown li {
  margin-bottom: 0.5rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ============================================================
   TABLE STYLING
   ============================================================ */

.rendered-markdown table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.875rem;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border);
}

.rendered-markdown th {
  background: var(--bg-surface);
  color: var(--text-primary);
  text-align: left;
  font-weight: 600;
  padding: 0.85rem 1rem;
  border-bottom: 1px solid var(--border);
}

.rendered-markdown td {
  padding: 0.85rem 1rem;
  border-bottom: 1px solid var(--border);
  color: var(--text-secondary);
}

.rendered-markdown tr:last-child td {
  border-bottom: none;
}

.rendered-markdown tr:nth-child(even) {
  background: rgba(255, 255, 255, 0.015);
}

body.light-mode .rendered-markdown tr:nth-child(even) {
  background: rgba(0, 0, 0, 0.015);
}

/* ============================================================
   NOTES, TIPS & WARNINGS CALLOUTS
   ============================================================ */

.callout {
  padding: 1.25rem 1.5rem;
  border-left: 4px solid var(--border);
  border-radius: var(--radius-sm);
  margin: 1.5rem 0;
  background: rgba(255, 255, 255, 0.01);
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}

.callout-icon {
  font-size: 1.15rem;
  flex-shrink: 0;
  margin-top: 0.15rem;
}

.callout-content {
  flex: 1;
}

.callout-content p:last-child {
  margin-bottom: 0;
}

.callout.callout-note {
  border-left-color: var(--accent);
  background: rgba(59, 130, 246, 0.05);
}
.callout.callout-note .callout-icon {
  color: var(--accent);
}

.callout.callout-tip {
  border-left-color: #10b981;
  background: rgba(16, 185, 129, 0.05);
}
.callout.callout-tip .callout-icon {
  color: #10b981;
}

.callout.callout-warning {
  border-left-color: #f59e0b;
  background: rgba(245, 158, 11, 0.05);
}
.callout.callout-warning .callout-icon {
  color: #f59e0b;
}

.callout.callout-mistake {
  border-left-color: #ef4444;
  background: rgba(239, 68, 68, 0.05);
}
.callout.callout-mistake .callout-icon {
  color: #ef4444;
}

/* ============================================================
   SYNTAX HIGHLIGHTING & CODE BLOCKS
   ============================================================ */

.rendered-markdown code {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.85em;
  background: rgba(255, 255, 255, 0.06);
  padding: 0.15rem 0.35rem;
  border-radius: var(--radius-sm);
  color: var(--text-primary);
}

body.light-mode .rendered-markdown code {
  background: rgba(0, 0, 0, 0.05);
}

.code-block-wrapper {
  position: relative;
  margin: 1.5rem 0;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  overflow: hidden;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.15);
}

.code-block-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.65rem 1.25rem;
  background: #0f1115;
  border-bottom: 1px solid var(--border);
  font-size: 0.75rem;
  color: var(--text-muted);
}

.code-lang-label {
  font-family: "JetBrains Mono", monospace;
  text-transform: uppercase;
  font-weight: 600;
  color: var(--text-secondary);
}

.copy-code-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  transition: var(--t);
  font-size: 0.8rem;
  display: flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.25rem 0.5rem;
  border-radius: var(--radius-sm);
}

.copy-code-btn:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
}

.code-block-wrapper pre {
  margin: 0 !important;
  padding: 1.25rem !important;
  background: #0d0f12 !important;
  overflow-x: auto;
}

.code-block-wrapper pre code {
  padding: 0 !important;
  background: transparent !important;
  font-size: 0.85rem !important;
  line-height: 1.6 !important;
  color: #e2e8f0;
}

/* ============================================================
   EXAMPLE OUTPUTS & EXPERIMENTS
   ============================================================ */

.example-output-container {
  margin: 1.5rem 0;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--bg-elevated);
}

.example-output-header {
  padding: 0.65rem 1.25rem;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.example-output-header i {
  color: #10b981;
}

.example-output-preview {
  padding: 1.5rem;
  background: var(--bg-primary);
}

.preview-box {
  padding: 1rem;
  border-radius: var(--radius-md);
  border: 1px dashed var(--border-hover);
  background: var(--bg-elevated);
}

.collapsible-solution {
  margin: 1rem 0;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.solution-trigger {
  width: 100%;
  text-align: left;
  background: var(--bg-surface);
  border: none;
  padding: 0.85rem 1.25rem;
  color: var(--text-primary);
  font-weight: 600;
  font-size: 0.85rem;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  outline: none;
  transition: var(--t);
}

.solution-trigger:hover {
  background: var(--bg-elevated);
}

.solution-trigger i {
  transition: transform 0.2s ease;
  color: var(--text-muted);
}

.collapsible-solution.open .solution-trigger i {
  transform: rotate(180deg);
}

.solution-content {
  display: none;
  padding: 1.25rem;
  background: rgba(255, 255, 255, 0.005);
  border-top: 1px solid var(--border);
}

.collapsible-solution.open .solution-content {
  display: block;
}

.practices-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  margin: 1.5rem 0;
}

.practice-card {
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.01);
  border: 1px solid var(--border);
}

.practice-card.best-practices {
  border-top: 3px solid #10b981;
}

.practice-card.common-mistakes {
  border-top: 3px solid #ef4444;
}

.practice-card h4 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.practice-card.best-practices h4 {
  color: #10b981;
}

.practice-card.common-mistakes h4 {
  color: #ef4444;
}

.practice-card ul {
  padding-left: 1.15rem;
  margin-bottom: 0;
}

.practice-card li {
  font-size: 0.8rem;
  margin-bottom: 0.35rem;
}

.vector-flowchart {
  margin: 2rem 0;
  padding: 1.5rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: rgba(15, 23, 42, 0.4);
  box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.1);
  text-align: center;
}

.vector-flowchart svg {
  max-width: 100%;
  height: auto;
}

.svg-node {
  fill: #161a1e;
  stroke: #2a3038;
  stroke-width: 1.5;
  transition: all 0.3s ease;
}

.svg-node:hover {
  fill: var(--accent-dim);
  stroke: var(--accent);
  filter: drop-shadow(0 0 6px rgba(59, 130, 246, 0.3));
}

.svg-text {
  font-family: inherit;
  font-weight: 500;
  fill: var(--text-primary);
  font-size: 11px;
}

.svg-text-heading {
  font-weight: bold;
  font-size: 12px;
}

.svg-line {
  stroke: #4a5568;
  stroke-width: 1.5;
}

.svg-marker {
  fill: #4a5568;
}

/* ============================================================
   PREVIOUS / NEXT TOPIC FOOTER NAVIGATION
   ============================================================ */

.topic-navigation {
  display: flex;
  justify-content: space-between;
  gap: 1.5rem;
  margin-top: 3.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

.nav-prev,
.nav-next {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  text-decoration: none;
  transition: var(--t);
}

.nav-prev {
  align-items: flex-start;
  text-align: left;
}

.nav-next {
  align-items: flex-end;
  text-align: right;
}

.nav-prev:hover,
.nav-next:hover {
  border-color: var(--border-accent);
  background: var(--bg-surface);
  transform: translateY(-2px);
}

.nav-dir {
  font-size: 0.75rem;
  color: var(--accent);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.35rem;
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.nav-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
}

.nav-prev.disabled,
.nav-next.disabled {
  opacity: 0.3;
  pointer-events: none;
}

/* ============================================================
   FOOTER STYLES
   ============================================================ */

.footer {
  position: relative;
  background: var(--bg-elevated);
  border-top: 1px solid var(--border);
  padding: 3rem 2rem 2rem;
  margin-top: 2rem;
  z-index: 10;
  clear: both;
  width: 100%;
  backdrop-filter: blur(4px);
}

.footer-content {
  max-width: 1280px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 2.5rem;
  align-items: start;
}

.footer h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--text-primary);
  letter-spacing: -0.3px;
}

.footer p {
  color: var(--text-secondary);
  line-height: 1.6;
  font-size: 0.9rem;
  margin: 0;
}

.social-links {
  display: flex;
  gap: 1rem;
  margin-top: 0.5rem;
  flex-wrap: wrap;
}

.social-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-surface);
  color: var(--text-primary);
  transition: var(--t);
  border: 1px solid var(--border);
  font-size: 1.2rem;
  text-decoration: none;
}

.social-btn:hover {
  background: var(--accent-dim);
  color: var(--accent);
  border-color: var(--accent);
  transform: translateY(-3px);
}

.featured-btn {
  background: linear-gradient(135deg, var(--accent), #6366f1);
  border: none;
  padding: 0.6rem 1.2rem;
  border-radius: 40px;
  font-weight: 600;
  font-size: 0.85rem;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: white;
  transition: var(--t);
}

.featured-btn:hover {
  transform: scale(1.02);
  box-shadow: 0 8px 20px rgba(59, 130, 246, 0.3);
  color: white;
}

body.light-mode .footer {
  background: rgba(255, 255, 255, 0.92);
}

/* ============================================================
   RESPONSIVE
   ============================================================ */

@media (max-width: 992px) {
  .learning-container {
    grid-template-columns: 1fr;
  }

  .learning-sidebar {
    position: fixed;
    top: 60px;
    left: 0;
    width: 300px;
    height: calc(100vh - 60px);
    transform: translateX(-100%);
    box-shadow: 20px 0 40px rgba(0, 0, 0, 0.4);
    z-index: 1002;
    overflow-x: visible;
    overflow-y: hidden;
  }

  .learning-sidebar.active {
    transform: translateX(0);
  }

  .sidebar-toggle-btn {
    display: inline-flex;
  }

  .learning-content {
    padding: 1.5rem 1.5rem 3rem;
  }

  .practices-grid {
    grid-template-columns: 1fr;
  }

  .footer {
    padding: 2rem 1.5rem 1.5rem;
  }

  .footer-content {
    gap: 1.8rem;
  }
}

@media (max-width: 640px) {
  .topic-navigation {
    flex-direction: column;
    gap: 1rem;
  }
  .progress-stats-grid {
    grid-template-columns: 1fr;
  }

  .nav-prev,
  .nav-next {
    align-items: center;
    text-align: center;
  }

  .footer-content {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .social-links {
    justify-content: center;
  }
}

/* Light mode overrides */
body.light-mode .reading-progress-container {
  background: rgba(0, 0, 0, 0.02);
}

body.light-mode .code-block-header {
  background: #f1f5f9;
  border-bottom-color: #e2e8f0;
}

body.light-mode .code-block-wrapper pre {
  background: #f8fafc !important;
  border-top: none;
}

body.light-mode .code-block-wrapper pre code {
  color: #334155 !important;
}

body.light-mode .svg-node {
  fill: #ffffff;
  stroke: #cbd5e1;
}

body.light-mode .svg-node:hover {
  fill: #eff6ff;
  stroke: var(--accent);
}

body.light-mode .svg-text {
  fill: #1e293b;
}

body.light-mode .svg-line {
  stroke: #94a3b8;
}

body.light-mode .svg-marker {
  fill: #94a3b8;
}

body.light-mode .vector-flowchart {
  background: rgba(241, 245, 249, 0.5);
  border-color: #e2e8f0;
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ============================================================
   QUIZ STYLES
   ============================================================ */

.quiz-container {
  margin-top: 2rem;
}

.quiz-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  text-align: center;
  max-width: 900px;
  margin: 0 auto;
}

.quiz-card h3 {
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.quiz-card p {
  color: var(--text-secondary);
}

.start-quiz-btn {
  margin-top: 1rem;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--radius-md);
  background: var(--accent);
  color: white;
  cursor: pointer;
  font-weight: 600;
  transition: 0.3s ease;
}

.start-quiz-btn:hover {
  opacity: 0.9;
  transform: translateY(-2px);
}

.quiz-question {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 1rem 0;
}

.quiz-options {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin: 1rem 0;
}

.quiz-option {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  cursor: pointer;
  color: var(--text-primary);
  background: var(--bg-elevated);
  font-size: 15px;
  font-weight: 500;
}

.quiz-option input[type="radio"] {
  accent-color: var(--accent);
  flex-shrink: 0;
}

.quiz-option:hover {
  border-color: var(--accent);
  background: var(--bg-surface);
}

.quiz-option.selected {
  border-color: var(--accent);
  background: rgba(59, 130, 246, 0.12);
}

.submit-answer-btn,
.retake-btn {
  padding: 12px 20px;
  border: none;
  border-radius: 10px;
  background: var(--accent);
  color: white;
  cursor: pointer;
  margin-top: 1rem;
}

.quiz-result-card {
  text-align: center;
  padding: 2rem;
  border-radius: 16px;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
}

.quiz-score {
  font-size: 2rem;
  font-weight: 700;
  margin: 1rem 0;
}

.quiz-correct {
  color: #10b981;
  font-weight: 700;
  margin-top: 16px;
}

.quiz-wrong {
  color: #ef4444;
  font-weight: 700;
  margin-top: 16px;
}

/* ============================================================
   PROGRESS STYLES
   ============================================================ */

.learning-progress-header {
  margin-bottom: 1.5rem;
}
.learning-dashboard-header {
  margin-bottom: 2rem;
}


.progress-stat-card:hover {
  transform: translateY(-2px);

  border-color: var(--accent);
}
.stat-label {
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-bottom: 6px;
}
.progress-stat-card strong {
  font-size: 1.4rem;
  font-weight: 700;
}

.continue-learning-btn {
  padding: 10px 18px;
  border: none;
  border-radius: 10px;
  background: var(--accent);
  color: white;
  cursor: pointer;
  font-weight: 600;
  margin-bottom: 15px;
}

.continue-learning-btn:hover {
  opacity: 0.9;
}

.overall-progress {
  margin-bottom: 1rem;
}

.progress-label {
  display: flex;
  justify-content: space-between;
  margin-bottom: 8px;
  font-size: 14px;
}

.progress-bar {
  height: 10px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 999px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #3b82f6, #60a5fa);
  transition: width 0.3s ease;
}

.topic-item.completed a {
  color: #22c55e;
}

.topic-item.completed a::after {
  content: "✓";
  float: right;
  font-weight: bold;
}


/* ==========================================
   BOOKMARKS
   ========================================== */

.bookmarks-container {
  margin: 1rem;
  padding: 1rem;

  border: 1px solid var(--border);

  border-radius: var(--radius-md);

  background: var(--bg-elevated);
}

.bookmarks-header {
  display: flex;

  align-items: center;

  gap: 0.5rem;

  margin-bottom: 0.75rem;

  font-weight: 600;

  color: #fbbf24;
}

.bookmarks-list {
  list-style: none;

  padding: 0;

  margin: 0;
}

.bookmarks-list li {
  margin-bottom: 0.5rem;
}

.bookmarks-list a {
  display: block;

  padding: 0.5rem;

  border-radius: var(--radius-sm);

  text-decoration: none;

  color: var(--text-secondary);

  transition: var(--t);
}

.bookmarks-list a:hover {
  background: var(--bg-surface);

  color: var(--text-primary);
}

.empty-bookmark {
  color: var(--text-muted);

  font-size: 0.85rem;
}

.bookmark-btn {
  display: inline-flex;

  align-items: center;

  gap: 0.5rem;

  margin-top: 1rem;

  padding: 0.65rem 1rem;

  border-radius: 999px;

  border: 1px solid var(--border);

  background: var(--bg-elevated);

  color: var(--text-primary);

  cursor: pointer;

  transition: var(--t);
}

.topic-title-row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 0.5rem;
}

.topic-title-row h1 {
  margin: 0;
}
.bookmark-icon-btn {
  border: none;
  background: transparent;
  color: #9ca3af;
  font-size: 24px;
  cursor: pointer;
  padding: 0;
  width: auto;
  height: auto;
}

.bookmark-icon-btn:hover {
  color: #fbbf24;

  transform: scale(1.08);
}

.bookmark-icon-btn.active {
  color: #fbbf24;

  border-color: #fbbf24;
}

.bookmark-btn:hover {
  border-color: #fbbf24;

  transform: translateY(-1px);
}

.bookmark-btn.active {
  color: #fbbf24;

  border-color: #fbbf24;
}

/* Sidebar Topic Row */
.topic-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  width: 100%;
}

/* Topic link takes remaining space */
.topic-row a {
  flex: 1;
  min-width: 0;
}

/* Sidebar bookmark star */
.sidebar-bookmark-btn {
  background: transparent;
  border: none;
  color: #9ca3af;
  cursor: pointer;
  font-size: 16px;
  padding: 4px;
  flex-shrink: 0;
  transition: all 0.2s ease;
}

.sidebar-bookmark-btn:hover {
  color: #fbbf24;
  transform: scale(1.1);
}

/* =====================================
   LEARNING ROADMAP
   ===================================== */

.learning-roadmap-card {
  margin-bottom: 1.5rem;

  padding: 1.25rem;

  border-radius: var(--radius-lg);

  border: 1px solid var(--border);

  background: var(--bg-elevated);
}

.roadmap-header {
  display: flex;

  align-items: center;

  gap: .5rem;

  color: var(--accent);

  margin-bottom: 1rem;

  font-weight: 700;
}

.roadmap-content h3 {
  margin-bottom: .5rem;
}

.roadmap-content p {
  color: var(--text-secondary);

  margin-bottom: 1rem;
}

.recommended-topic-btn {
  display: inline-flex;

  align-items: center;

  justify-content: center;

  padding: .7rem 1rem;

  border-radius: 10px;

  text-decoration: none;

  background: var(--accent);

  color: white;

  font-weight: 600;
}

.recommended-topic-btn:hover {
  opacity: .9;
}

.streak-card {
  border: 1px solid rgba(255,140,0,.25);
}

.streak-card strong {
  color: #f97316;
}

@media (max-width: 768px) {
  .progress-stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

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