.lh-header {
  position: relative;
  padding: 5rem 0 3.5rem;
  overflow: hidden;
}
.lh-header-bg { position: absolute; inset: 0; z-index: 0; }

.lh-hero {
  position: relative;
  z-index: 1;
  max-width: 620px;
}
.lh-hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.1;
  margin: 0.5rem 0 1rem;
}
.lh-hero-sub {
  font-size: 1.05rem;
  color: var(--clr-text-muted);
  line-height: 1.65;
  margin: 0 0 2rem;
  max-width: 480px;
}

.lh-hero-stats {
  display: inline-flex;
  flex-direction: row;
  align-items: center;
  gap: 1.5rem;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: 0.875rem 1.5rem;
  width: auto;
}
.lh-hstat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
  flex-shrink: 0;
}
.lh-hstat span {
  display: block;
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--clr-accent);
  line-height: 1;
  white-space: nowrap;
}
.lh-hstat label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--clr-text-dim);
  white-space: nowrap;
  cursor: default;
}
.lh-hstat-sep {
  flex-shrink: 0;
  width: 1px;
  height: 28px;
  background: var(--clr-border);
}

.lh-filterbar {
  background: var(--clr-surface);
  border-top: 1px solid var(--clr-border);
  border-bottom: 1px solid var(--clr-border);
  padding: 0.75rem 0;
  position: sticky;
  top: 70px;
  z-index: 100;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: rgba(18,24,35,0.9);
}
[data-theme="light"] .lh-filterbar { background: rgba(255,255,255,0.92); }

.lh-filter-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.lh-tabs {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  background: var(--clr-bg);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  padding: 0.25rem;
}
.lh-tab {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.45rem 1rem;
  border-radius: calc(var(--radius-md) - 3px);
  font-size: 0.825rem;
  font-weight: 500;
  font-family: var(--font-body);
  color: var(--clr-text-muted);
  background: none;
  border: none;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.2s, color 0.2s;
}
.lh-tab:hover { background: var(--clr-surface-2); color: var(--clr-text); }
.lh-tab.active {
  background: var(--clr-accent);
  color: #0a0e14;
  font-weight: 600;
}
[data-theme="light"] .lh-tab.active { color: #fff; }

.lh-filter-count {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--clr-text-dim);
  white-space: nowrap;
}

.lh-courses-section { padding: 3rem 0 5rem; }

.lh-courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
}

.lh-card {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: 1.625rem;
  color: var(--clr-text);
  text-decoration: none;
  position: relative;
  overflow: hidden;
  transition:
    transform 0.3s var(--ease-out),
    border-color 0.3s,
    box-shadow 0.3s;
}

.lh-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--cc, var(--clr-accent));
  border-radius: 3px 3px 0 0;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.35s var(--ease-out);
}

.lh-card::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at top left, color-mix(in srgb, var(--cc, var(--clr-accent)) 6%, transparent), transparent 65%);
  opacity: 0;
  transition: opacity 0.4s;
  pointer-events: none;
}
.lh-card:not(.lh-card--soon):hover {
  transform: translateY(-6px);
  border-color: var(--clr-border-2);
  box-shadow: 0 12px 40px rgba(0,0,0,0.35), 0 1px 0 rgba(255,255,255,0.04) inset;
}
.lh-card:not(.lh-card--soon):hover::before { transform: scaleX(1); }
.lh-card:not(.lh-card--soon):hover::after  { opacity: 1; }

.lh-card--soon {
  opacity: 0.62;
  cursor: default;
}
.lh-card--soon:hover { transform: none; box-shadow: none; border-color: var(--clr-border); }

.lh-soon-badge {
  position: absolute;
  top: 1rem; right: 1rem;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: var(--clr-surface-2);
  border: 1px solid var(--clr-border-2);
  color: var(--clr-text-dim);
  padding: 0.25rem 0.6rem;
  border-radius: 99px;
}

.lh-card-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  min-width: 52px;
  min-height: 52px;
  border-radius: var(--radius-md);
  border: 1px solid;
  flex-shrink: 0;
  overflow: hidden;
  position: relative;
  z-index: 1;
}
.lh-card-icon svg {
  width: 24px !important;
  height: 24px !important;
  flex-shrink: 0;
}

.lh-card-body {
  flex: 1;
  position: relative;
  z-index: 1;
}
.lh-card-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.015em;
  line-height: 1.25;
  margin: 0 0 0.625rem;
  transition: color 0.2s;
}
.lh-card:not(.lh-card--soon):hover .lh-card-title {
  color: var(--cc, var(--clr-accent));
}
.lh-card-desc {
  font-size: 0.875rem;
  color: var(--clr-text-muted);
  line-height: 1.6;
  margin: 0;
}

.lh-card-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1rem;
  border-top: 1px solid var(--clr-border);
  position: relative;
  z-index: 1;
}
.lh-card-pills {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}
.lh-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  padding: 0.25rem 0.6rem;
  border-radius: 99px;
  border: 1px solid;
}
.lh-card-arrow {
  display: flex;
  align-items: center;
  transition: transform 0.25s var(--ease-out);
}
.lh-card:not(.lh-card--soon):hover .lh-card-arrow {
  transform: translateX(5px);
}
.lh-card-lock { color: var(--clr-text-dim); display: flex; }

.lh-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
  padding: 5rem 2rem;
  text-align: center;
  color: var(--clr-text-muted);
}
.lh-empty svg { opacity: 0.25; margin-bottom: 0.5rem; }
.lh-empty p   { font-size: 1rem; margin: 0; }

.lh-coming {
  border-top: 1px solid var(--clr-border);
  background: var(--clr-surface);
  padding: 1.125rem 0;
}
.lh-coming-inner {
  display: flex;
  align-items: center;
  gap: 0.875rem;
}
.lh-coming-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 30px; height: 30px;
  border-radius: var(--radius-sm);
  background: rgba(30,155,255,0.08);
  border: 1px solid rgba(30,155,255,0.2);
  color: var(--clr-accent);
  flex-shrink: 0;
}
.lh-coming-inner p {
  font-size: 0.875rem;
  color: var(--clr-text-muted);
  margin: 0;
  line-height: 1.5;
}
.lh-coming-inner strong { color: var(--clr-text); }

.lh-note {
  display: flex;
  align-items: center;
  gap: 0.875rem;
  margin-top: 2.5rem;
  padding: 0.875rem 1.125rem;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border-2);
  border-left: 3px solid var(--clr-accent);
  border-radius: var(--radius-md);
}
.lh-note svg { color: var(--clr-accent); flex-shrink: 0; }
.lh-note p {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.5;
  color: var(--clr-text-muted);
}
.lh-note strong { color: var(--clr-text); }
.lh-note a {
  color: var(--clr-accent);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 3px;
}
.lh-note--top { margin-top: 0; margin-bottom: 2rem; }

[data-theme="light"] .lh-card {
  box-shadow: 0 2px 12px rgba(0,0,0,0.05);
}
[data-theme="light"] .lh-card:not(.lh-card--soon):hover {
  box-shadow: 0 12px 40px rgba(0,0,0,0.12);
}

@media (max-width: 768px) {
  .lh-courses-grid { grid-template-columns: 1fr; gap: 1rem; }
  .lh-hero-stats   { flex-wrap: wrap; }
}
@media (max-width: 560px) {
  .lh-note { align-items: flex-start; margin-top: 2rem; }
  .lh-note--top { margin-top: 0; margin-bottom: 1.5rem; }
  .lh-tabs { flex-wrap: wrap; gap: 0.25rem; }
  .lh-tab  { font-size: 0.78rem; padding: 0.4rem 0.75rem; }
  .lh-filter-inner { flex-direction: column; align-items: flex-start; }
}

.course-hero {
  display: flex;
  align-items: flex-start;
  gap: 1.5rem;
  padding: 2.5rem 0 2rem;
  border-bottom: 1px solid var(--clr-border);
  margin-bottom: 2.5rem;
}
.course-hero-icon {
  flex-shrink: 0;
  width: 52px;
  height: 52px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--clr-surface-2);
  border: 1px solid var(--clr-border);
}
.course-hero-icon svg {
  width: 26px;
  height: 26px;
}
.course-hero-icon.tag-accent { background: rgba(30,155,255,0.1); border-color: rgba(30,155,255,0.25); color: #1e9bff; }
.course-hero-icon.tag-cyan  { background: rgba(108,200,255,0.1); border-color: rgba(108,200,255,0.25); color: #6cc8ff; }
.course-hero-icon.tag-purple{ background: rgba(140,196,255,0.1); border-color: rgba(140,196,255,0.25); color: #8cc4ff; }
.course-hero-icon.tag-red   { background: rgba(248,113,113,0.1); border-color: rgba(248,113,113,0.25); color: #f87171; }
.course-hero-icon.tag-orange{ background: rgba(245,165,36,0.1); border-color: rgba(245,165,36,0.25); color: #f5a524; }
.course-hero-icon.tag-blue  { background: rgba(96,165,250,0.1); border-color: rgba(96,165,250,0.25); color: #60a5fa; }

.course-hero-body { flex: 1; min-width: 0; }
.course-hero-tags {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 0.6rem;
}
.course-badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
  border: 1px solid;
}
.course-badge-lessons {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--clr-text-dim);
}
.course-hero-title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--clr-text);
  margin-bottom: 0.5rem;
  line-height: 1.2;
}
.course-hero-desc {
  font-size: 0.95rem;
  color: var(--clr-text-muted);
  line-height: 1.65;
  max-width: 60ch;
  margin: 0;
}
@media (max-width: 600px) {
  .course-hero { flex-direction: row; gap: 1rem; }
  .course-hero-icon { width: 42px; height: 42px; border-radius: 10px; }
  .course-hero-icon svg { width: 20px; height: 20px; }
  .course-hero-title { font-size: 1.35rem; }
}

.course-hero-icon svg,
.tutorial-header .tag svg,
span.tag svg {
  width: 24px !important;
  height: 24px !important;
  max-width: 24px !important;
  max-height: 24px !important;
}

.tutorial-header span.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.72rem;
}
.tutorial-header span.tag svg {
  width: 14px !important;
  height: 14px !important;
  max-width: 14px !important;
  max-height: 14px !important;
  flex-shrink: 0;
}

@media (max-width: 900px) {
  .tutorial-layout {
    grid-template-columns: 1fr !important;
    gap: 1.5rem;
  }
  .tutorial-sidebar {
    position: static !important;
    top: auto;
    order: 1;
    max-height: 280px;
    overflow-y: auto;
  }
  .tutorial-content,
  article.prose {
    order: 2;
  }
}

@media (max-width: 600px) {
  .course-hero header,
  header[style*="display:flex"] {
    flex-direction: row !important;
    gap: 1rem !important;
  }
}

@media (max-width: 700px) {
  .lh-grid {
    grid-template-columns: 1fr !important;
  }
}

@media (max-width: 600px) {
  .tutorial-page { padding-top: 2rem !important; }
  .tutorial-header h1,
  h1#lessonTitle { font-size: 1.6rem !important; }
}

.lh-filter-inner {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.lh-search-wrap {
  position: relative;
  display: flex;
  align-items: center;
  margin-left: auto;
}
.lh-search-icon {
  position: absolute;
  left: 0.65rem;
  color: var(--clr-text-dim);
  pointer-events: none;
  flex-shrink: 0;
}
.lh-search-input {
  background: var(--clr-surface-2);
  border: 1px solid var(--clr-border-2);
  border-radius: var(--radius);
  padding: 0.4rem 2rem 0.4rem 2rem;
  font-size: 0.82rem;
  color: var(--clr-text);
  font-family: var(--font-sans);
  outline: none;
  width: 190px;
  transition: border-color 0.2s, box-shadow 0.2s, width 0.25s;
}
.lh-search-input::placeholder { color: var(--clr-text-dim); }
.lh-search-input:focus {
  border-color: var(--clr-accent);
  box-shadow: 0 0 0 3px rgba(30,155,255,0.12);
  width: 230px;
}
.lh-search-clear {
  position: absolute;
  right: 0.5rem;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--clr-text-dim);
  padding: 0.2rem;
  display: flex;
  align-items: center;
  transition: color 0.15s;
}
.lh-search-clear:hover { color: var(--clr-text); }

@media (max-width: 600px) {
  .lh-search-wrap { margin-left: 0; width: 100%; }
  .lh-search-input { width: 100% !important; }
  .lh-filter-inner { gap: 0.75rem; }
}