body { display: flex; flex-direction: column; background-color: #f7f9fb; }
.c-container { display: flex; flex: 1; max-width: 100%; }
.c-sidebar {
  width: 240px;
  background: #f5f5f5;
  padding: 1.5rem;
  border-right: 1px solid #ddd;
  position: sticky;
  top: 0;
  height: fit-content;
  max-height: 100vh;
  overflow-y: auto;
}
.c-sidebar h3 {
  font-size: 0.9rem;
  font-weight: 700;
  text-transform: uppercase;
  color: #666;
  margin: 0 0 1rem 0;
  letter-spacing: 0.05em;
}
.c-sidebar ul {
  list-style: none;
  padding: 0;
  margin: 0;
}
.c-sidebar li {
  margin: 0.3rem 0;
}
.c-sidebar a {
  color: #0066cc;
  text-decoration: none;
  font-size: 0.95rem;
  padding: 0.3rem 0.5rem;
  display: block;
  border-radius: 4px;
  transition: background 0.15s;
}
.c-sidebar a:hover {
  background: #e0e0e0;
}
.c-sidebar a.active {
  background: #512BD4;
  color: white;
}
.c-content {
  flex: 1;
  padding: 2rem;
  max-width: 900px;
}
.breadcrumb {
  font-size: 0.9rem;
  color: #666;
  margin-bottom: 1rem;
}
.breadcrumb a {
  color: #0066cc;
  text-decoration: none;
}
.breadcrumb a:hover {
  text-decoration: underline;
}
h1 {
  font-size: 2.5rem;
  margin-top: 0;
  margin-bottom: 0.5rem;
}
.intro-text {
  font-size: 1.1rem;
  color: #555;
  margin-bottom: 2rem;
}
.progress-bar {
  background: #f0f0f0;
  border-radius: 8px;
  height: 8px;
  margin: 2rem 0;
  overflow: hidden;
}
.progress-fill {
  background: linear-gradient(90deg, #512BD4, #764ba2);
  height: 100%;
  width: 0%;
  transition: width 0.3s ease;
}
.progress-text {
  font-size: 0.9rem;
  color: #666;
  margin-top: 0.3rem;
}
h2 {
  font-size: 1.8rem;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  border-bottom: 2px solid #512BD4;
  padding-bottom: 0.5rem;
}
h3 {
  font-size: 1.2rem;
  margin-top: 1.5rem;
  margin-bottom: 0.8rem;
}
.why-learn-list {
  list-style: none;
  padding: 0;
  margin: 1rem 0;
}
.why-learn-list li {
  padding: 0.8rem 1rem;
  margin: 0.5rem 0;
  background: #f9f9f9;
  border-left: 4px solid #512BD4;
}
.learning-path {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin: 1.5rem 0;
  align-items: center;
}
.path-step {
  background: #512BD4;
  color: #fff;
  padding: 1rem 1.5rem;
  border-radius: 8px;
  flex: 0 1 auto;
  text-align: center;
  font-weight: 600;
  font-size: 0.95rem;
}
.path-arrow {
  font-size: 1.5rem;
  color: #512BD4;
}
@media (max-width: 768px) {
  .learning-path {
    flex-direction: column;
  }
  .path-arrow {
    transform: rotate(90deg);
  }
}
details {
  margin: 1.5rem 0;
  border: 1px solid #ddd;
  border-radius: 8px;
  padding: 0;
  background: #fafafa;
}
details[open] {
  padding: 1rem;
}
summary {
  padding: 1rem;
  cursor: pointer;
  font-weight: 600;
  font-size: 1.05rem;
  user-select: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
summary:hover {
  background: #f0f0f0;
}
details[open] summary {
  border-bottom: 1px solid #ddd;
  margin-bottom: 1rem;
  padding-bottom: 1rem;
}
.lesson-content {
  margin-top: 0;
}
pre[class*="language-"] {
  background: #1e1e1e !important;
  border-radius: 6px;
  margin: 1rem 0;
}
.try-it-btn {
  display: inline-block;
  background: #512BD4;
  color: #fff;
  padding: 0.6rem 1.2rem;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  margin: 1rem 0;
  transition: background 0.2s;
  border: none;
  cursor: pointer;
  font-size: 0.95rem;
}
.try-it-btn:hover {
  background: #764ba2;
}
.completion-checkbox {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  margin-top: 1rem;
  padding: 0.8rem;
  background: #f5f0ff;
  border-radius: 6px;
}
.completion-checkbox input[type="checkbox"] {
  width: 18px;
  height: 18px;
  cursor: pointer;
  accent-color: #512BD4;
}
.projects-list {
  list-style: none;
  padding: 0;
  margin: 1.5rem 0;
}
.project-item {
  background: #f9f9f9;
  padding: 1.5rem;
  margin: 1rem 0;
  border-radius: 8px;
  border-left: 4px solid #512BD4;
}
.project-title {
  font-weight: 700;
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}
.project-meta {
  font-size: 0.9rem;
  color: #666;
  margin-bottom: 0.8rem;
}
.project-meta span {
  margin-right: 1.5rem;
}
.project-concepts {
  font-size: 0.95rem;
  margin-top: 0.8rem;
  color: #555;
}
.resources-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.5rem;
  margin: 1.5rem 0;
}
.resource-card {
  background: #f9f9f9;
  padding: 1.5rem;
  border-radius: 8px;
  border: 1px solid #ddd;
}
.resource-card h4 {
  margin-top: 0;
  margin-bottom: 1rem;
  color: #333;
}
.resource-card ul {
  list-style: none;
  padding: 0;
  margin: 0;
}
.resource-card li {
  margin: 0.5rem 0;
  font-size: 0.95rem;
}
.resource-card a {
  color: #512BD4;
  text-decoration: none;
}
.resource-card a:hover {
  text-decoration: underline;
}
.repos-section { margin: 3rem 0; }
.repos-controls { display: flex; flex-direction: column; gap: 1.5rem; margin-bottom: 2rem; }
.repos-search { display: flex; gap: 1rem; }
.repos-search input { flex: 1; padding: 0.8rem 1rem; border: 1px solid #ddd; border-radius: 6px; font-size: 1rem; font-family: inherit; }
.repos-search input:focus { outline: none; border-color: #512BD4; box-shadow: 0 0 0 3px rgba(81, 43, 212, 0.1); }
.repos-filters { display: flex; flex-wrap: wrap; gap: 0.8rem; }
.filter-btn { padding: 0.6rem 1.2rem; border: 2px solid #ddd; background: white; border-radius: 20px; cursor: pointer; font-weight: 600; font-size: 0.95rem; transition: all 0.2s; }
.filter-btn:hover { border-color: #512BD4; color: #512BD4; }
.filter-btn.active { background: #512BD4; color: white; border-color: #512BD4; }
.repos-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(450px, 100%), 1fr)); gap: 1.5rem; margin: 2rem 0; }
.repo-card { background: #fafafa; border: 1px solid #ddd; border-radius: 8px; padding: 1.5rem; transition: all 0.2s; }
.repo-card:hover { border-color: #512BD4; box-shadow: 0 4px 12px rgba(81, 43, 212, 0.15); transform: translateY(-2px); }
.repo-header { display: flex; justify-content: space-between; align-items: start; margin-bottom: 1rem; gap: 1rem; }
.repo-name { flex: 1; margin: 0; font-size: 1.1rem; }
.repo-name a { color: #512BD4; text-decoration: none; font-weight: 600; }
.repo-name a:hover { text-decoration: underline; }
.repo-stars { white-space: nowrap; font-weight: 600; color: #666; font-size: 0.95rem; }
.repo-meta { display: flex; flex-wrap: wrap; gap: 0.8rem; margin-bottom: 1rem; align-items: center; }
.category-badge { display: inline-block; padding: 0.3rem 0.8rem; border-radius: 12px; font-size: 0.8rem; font-weight: 600; text-transform: uppercase; }
.category-badge.learning { background: #dbeafe; color: #1e40af; }
.category-badge.patterns { background: #ede9fe; color: #6d28d9; }
.category-badge.project { background: #dcfce7; color: #15803d; }
.category-badge.tool { background: #fed7aa; color: #92400e; }
.activity-dot { display: inline-block; width: 8px; height: 8px; border-radius: 50%; margin: 0 0.3rem; }
.activity-dot.active { background: #22c55e; }
.activity-dot.recent { background: #eab308; }
.activity-dot.stale { background: #999; }
.last-commit { font-size: 0.85rem; color: #666; }
.license-badge { display: inline-block; padding: 0.2rem 0.6rem; background: #f0f0f0; border-radius: 4px; font-size: 0.8rem; color: #555; font-weight: 600; }
.repo-topics { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 1rem; }
.topic-tag { display: inline-block; padding: 0.3rem 0.6rem; background: #e8e8e8; color: #555; border-radius: 4px; font-size: 0.8rem; }
.repo-rationale { margin: 1rem 0; font-size: 0.95rem; color: #555; line-height: 1.5; }
.repo-link { display: inline-block; margin-top: 1rem; padding: 0.6rem 1.2rem; background: #512BD4; color: #fff; text-decoration: none; border-radius: 6px; font-weight: 600; font-size: 0.95rem; transition: background 0.2s; }
.repo-link:hover { background: #764ba2; }
.repos-loading { text-align: center; padding: 2rem; color: #666; }
.repos-error { padding: 1.5rem; background: #fee2e2; border: 1px solid #fecaca; border-radius: 6px; color: #991b1b; margin-bottom: 2rem; }
.repos-empty { text-align: center; padding: 2rem; color: #666; font-style: italic; }
@media (max-width: 768px) {
  .repos-grid { grid-template-columns: 1fr; }
  .repos-filters { flex-direction: column; }
  .filter-btn { width: 100%; text-align: center; }
  .repo-header { flex-direction: column; }
  .repo-stars { align-self: flex-start; }
}
@media (max-width: 900px) {
  .c-container {
    flex-direction: column;
  }
  .c-sidebar {
    width: 100%;
    position: static;
    border-right: none;
    border-bottom: 1px solid #ddd;
    max-height: none;
  }
  .c-content {
    padding: 1.5rem;
  }
}