/* ═══════════════════════════════════════════════
   EDUCATION COURSE STYLES
   Scoped to .edu-* classes only — no globals modified
   ═══════════════════════════════════════════════ */

/* ── Course Index Hero ── */
.edu-course { padding-top: calc(var(--nav-height) + 2rem); }

.edu-hero {
  text-align: center;
  padding: 3rem 0 2rem;
}

.edu-hero__badge {
  display: inline-block;
  padding: 0.35rem 1rem;
  background: rgba(0, 229, 255, 0.08);
  color: var(--accent-cyan);
  border: 1px solid rgba(0, 229, 255, 0.15);
  border-radius: 2rem;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
}

.edu-hero__title {
  font-size: 3.5rem;
  line-height: 1.1;
  margin-bottom: 1.25rem;
  background: linear-gradient(to right, #fff 30%, #9ca3af);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.edu-hero__subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.7;
}

/* ── What You'll Learn ── */
.edu-learn {
  margin: 3rem 0 2rem;
}

.edu-learn h2 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  color: var(--text-main);
}

.edu-learn__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1rem;
}

.edu-learn__item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  background: var(--bg-panel);
  border: 1px solid var(--border-color);
  border-radius: 0.75rem;
  font-size: 0.95rem;
  color: var(--text-main);
}

.edu-learn__item i {
  width: 20px;
  height: 20px;
  color: var(--accent-cyan);
  flex-shrink: 0;
}

/* ── Level Block ── */
.edu-level {
  margin: 3rem 0 1rem;
}

.edu-level__header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.edu-level__dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}

.edu-level__title {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 0;
  color: var(--text-main);
}

/* ── Part Cards ── */
.edu-parts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.25rem;
}

.edu-part-card {
  display: flex;
  gap: 1.25rem;
  padding: 1.5rem;
  background: var(--bg-panel);
  border: 1px solid var(--border-color);
  border-radius: 1rem;
  text-decoration: none;
  color: inherit;
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}

.edu-part-card:hover {
  transform: translateY(-4px);
  border-color: var(--level-color, var(--accent-blue));
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3);
}

.edu-part-card__number {
  font-family: var(--font-display);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--level-color, var(--accent-blue));
  opacity: 0.25;
  line-height: 1;
  flex-shrink: 0;
  min-width: 40px;
}

.edu-part-card__body {
  flex: 1;
}

.edu-part-card__icon {
  width: 36px;
  height: 36px;
  background: rgba(59, 130, 246, 0.08);
  border-radius: 0.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--level-color, var(--accent-blue));
  margin-bottom: 0.75rem;
}

.edu-part-card__icon i {
  width: 18px;
  height: 18px;
}

.edu-part-card__title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--text-main);
}

.edu-part-card__summary {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 0.75rem;
}

.edu-part-card__cta {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--level-color, var(--accent-blue));
  transition: gap 0.2s ease;
}

.edu-part-card:hover .edu-part-card__cta { gap: 0.6rem; }

/* ═══════════════════════════════════════════════
   LESSON PAGE
   ═══════════════════════════════════════════════ */
.edu-lesson { padding-top: calc(var(--nav-height) + 1rem); }

.edu-lesson__layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 2.5rem;
  align-items: start;
}

/* ── Sidebar ── */
.edu-sidebar {
  position: sticky;
  top: calc(var(--nav-height) + 1.5rem);
  max-height: calc(100vh - var(--nav-height) - 3rem);
  overflow-y: auto;
  padding-right: 0.5rem;
}

.edu-sidebar__header {
  margin-bottom: 1rem;
}

.edu-sidebar__back {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--accent-blue);
  text-decoration: none;
  padding: 0.4rem 0;
  transition: color 0.2s;
}

.edu-sidebar__back:hover { color: var(--accent-cyan); }

.edu-sidebar__label {
  font-size: 0.65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  padding: 0 0.4rem;
}

.edu-sidebar__parts {
  margin-bottom: 1.5rem;
}

.edu-sidebar__part-link {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem;
  border-radius: 0.4rem;
  text-decoration: none;
  font-size: 0.78rem;
  color: var(--text-muted);
  transition: all 0.15s ease;
}

.edu-sidebar__part-link:hover { color: var(--text-main); background: rgba(255,255,255,0.03); }
.edu-sidebar__part-link.active { color: var(--accent-blue); font-weight: 600; background: rgba(59,130,246,0.08); }

.edu-sidebar__part-num {
  width: 20px;
  height: 20px;
  background: rgba(255,255,255,0.05);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-weight: 700;
  flex-shrink: 0;
}

.edu-sidebar__part-link.active .edu-sidebar__part-num {
  background: rgba(59,130,246,0.15);
  color: var(--accent-blue);
}

.edu-sidebar__sections {
  border-top: 1px solid var(--border-color);
  padding-top: 1rem;
}

.edu-sidebar__link {
  display: block;
  padding: 0.35rem 0.4rem;
  border-radius: 0.3rem;
  font-size: 0.75rem;
  color: var(--text-muted);
  text-decoration: none;
  line-height: 1.4;
  transition: all 0.15s ease;
  border-left: 2px solid transparent;
  margin-bottom: 1px;
}

.edu-sidebar__link:hover { color: var(--text-main); }
.edu-sidebar__link.active {
  color: var(--accent-blue);
  border-left-color: var(--accent-blue);
  background: rgba(59,130,246,0.05);
}

/* ── Lesson Header ── */
.edu-lesson__header {
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border-color);
}

.edu-lesson__level-badge {
  display: inline-block;
  padding: 0.2rem 0.7rem;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--level-color);
  background: color-mix(in srgb, var(--level-color) 10%, transparent);
  border: 1px solid color-mix(in srgb, var(--level-color) 20%, transparent);
  border-radius: 1rem;
  margin-bottom: 1rem;
}

.edu-lesson__part-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-muted);
  margin-bottom: 0.25rem;
}

.edu-lesson__title {
  font-size: 2.25rem;
  line-height: 1.2;
  margin-bottom: 0.75rem;
}

.edu-lesson__summary {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ── Reading Progress ── */
.edu-progress {
  margin-top: 1.5rem;
  height: 3px;
  background: rgba(255,255,255,0.06);
  border-radius: 3px;
  overflow: hidden;
}

.edu-progress__bar {
  height: 100%;
  width: 0;
  background: linear-gradient(to right, var(--accent-blue), var(--accent-cyan));
  border-radius: 3px;
  transition: width 0.1s ease-out;
}

/* ── Section Content ── */
.edu-section {
  margin-bottom: 3rem;
  scroll-margin-top: calc(var(--nav-height) + 2rem);
}

.edu-section__title {
  font-size: 1.4rem;
  font-weight: 600;
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-main);
}

.edu-section__content {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-main);
}

.edu-section__content p {
  margin-bottom: 1rem;
  color: var(--text-main);
}

.edu-section__content h4 {
  font-size: 1.05rem;
  font-weight: 600;
  margin: 1.5rem 0 0.75rem;
  color: var(--accent-cyan);
}

.edu-section__content ul,
.edu-section__content ol {
  margin: 0.75rem 0 1rem 1.25rem;
}

.edu-section__content li {
  margin-bottom: 0.4rem;
  color: var(--text-main);
}

.edu-section__content strong {
  color: #fff;
  font-weight: 600;
}

.edu-section__content code {
  font-family: 'JetBrains Mono', monospace;
  padding: 0.1rem 0.4rem;
  background: rgba(59, 130, 246, 0.1);
  border-radius: 4px;
  font-size: 0.9em;
  color: var(--accent-cyan);
}

/* ── Prev / Next Navigation ── */
.edu-nav-footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
  margin-top: 2rem;
}

.edu-nav-btn {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  background: var(--bg-panel);
  border: 1px solid var(--border-color);
  border-radius: 0.75rem;
  text-decoration: none;
  color: var(--text-main);
  transition: all 0.2s ease;
  max-width: 48%;
}

.edu-nav-btn:hover {
  border-color: var(--accent-blue);
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.edu-nav-btn--next { margin-left: auto; text-align: right; }
.edu-nav-btn--prev { margin-right: auto; }

.edu-nav-btn__label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 0.15rem;
}

.edu-nav-btn__title {
  font-size: 0.9rem;
  font-weight: 600;
}

.edu-nav-btn i { color: var(--accent-blue); flex-shrink: 0; }

/* ═══════════════════════════════════════════════
   MOBILE RESPONSIVE
   ═══════════════════════════════════════════════ */
@media (max-width: 900px) {
  .edu-lesson__layout {
    grid-template-columns: 1fr;
  }

  .edu-sidebar {
    position: relative;
    top: 0;
    max-height: none;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 1rem;
    margin-bottom: 1rem;
  }

  .edu-sidebar__sections { display: none; }
}

@media (max-width: 768px) {
  .edu-hero__title { font-size: 2.2rem; }
  .edu-lesson__title { font-size: 1.6rem; }
  .edu-parts-grid { grid-template-columns: 1fr; }
  .edu-nav-footer { flex-direction: column; }
  .edu-nav-btn { max-width: 100%; }
  .edu-nav-btn--next { margin-left: 0; text-align: left; }
  .edu-learn__grid { grid-template-columns: 1fr; }
  
  /* Prevent double padding with .main-wrapper */
  .edu-course, .edu-lesson {
    padding-top: 1rem !important;
  }
  
  .edu-section {
    scroll-margin-top: calc(var(--nav-height) + 1rem);
  }
}