/* ================================================================
   BRAND SCALING COURSE — Premium Dark Theme
   ================================================================ */

:root {
  --sidebar-bg:        #161b27;
  --sidebar-hover:     #1d2436;
  --sidebar-active:    #1a2a45;
  --content-bg:        #0d1117;
  --card-bg:           #161b27;
  --card-hover:        #1d2436;
  --border:            #21293a;
  --border-light:      #2d3a52;
  --text-primary:      #e6edf3;
  --text-secondary:    #8b949e;
  --text-muted:        #4a5568;
  --accent:            #4f8ef7;
  --accent-hover:      #79aaff;
  --accent-dim:        rgba(79,142,247,0.12);
  --green:             #3fb950;
  --green-dim:         rgba(63,185,80,0.12);
  --green-glow:        rgba(63,185,80,0.25);
  --yellow:            #d29922;
  --yellow-dim:        rgba(210,153,34,0.12);
  --red:               #f85149;
  --sidebar-width:     260px;
  --right-width:       230px;
  --font:              -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  --mono:              'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
}

/* ── Reset ─────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 15px; -webkit-font-smoothing: antialiased; }
body { font-family: var(--font); background: var(--content-bg); color: var(--text-primary); line-height: 1.6; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-hover); text-decoration: underline; }
img { max-width: 100%; }

/* ── Page Layout ────────────────────────────────────────────────── */
.layout {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* ================================================================
   LEFT SIDEBAR
   ================================================================ */
.left-sidebar {
  width: var(--sidebar-width);
  flex-shrink: 0;
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  height: 100vh;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
  z-index: 10;
}
.left-sidebar::-webkit-scrollbar { width: 4px; }
.left-sidebar::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }

.sidebar-header {
  padding: 1.1rem 1rem 0.9rem;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.brand-name {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-primary);
  display: block;
  margin-bottom: 0.9rem;
  text-decoration: none;
}
.brand-name:hover { color: var(--accent); text-decoration: none; }

/* Progress */
.progress-label {
  display: flex;
  justify-content: space-between;
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 0.45rem;
}
.progress-label .pct { color: var(--accent); }
.progress-track {
  height: 3px;
  background: var(--border);
  border-radius: 2px;
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), #79aaff);
  border-radius: 2px;
  transition: width 0.5s ease;
  width: 0%;
}

/* Nav */
.sidebar-nav {
  flex: 1;
  padding: 0.6rem 0;
  overflow-y: visible;
}

.nav-group-label {
  padding: 0.65rem 1rem 0.25rem;
  font-size: 0.64rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.4rem 0.65rem 0.4rem 0.9rem;
  font-size: 0.81rem;
  color: var(--text-secondary);
  cursor: pointer;
  border-radius: 5px;
  margin: 1px 0.4rem;
  transition: background 0.12s, color 0.12s;
  text-decoration: none;
  position: relative;
  line-height: 1.35;
}
.nav-item:hover { background: var(--sidebar-hover); color: var(--text-primary); text-decoration: none; }
.nav-item.active {
  background: var(--sidebar-active);
  color: var(--accent);
  font-weight: 500;
}
.nav-item.active::before {
  content: '';
  position: absolute;
  left: 0.4rem;
  top: 25%;
  bottom: 25%;
  width: 2px;
  background: var(--accent);
  border-radius: 2px;
}

/* Checkbox */
.nav-check {
  width: 15px;
  height: 15px;
  border: 1.5px solid var(--border-light);
  border-radius: 3px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 9px;
  transition: all 0.18s;
  color: transparent;
}
.nav-item.completed .nav-check {
  background: var(--green);
  border-color: var(--green);
  color: #fff;
}

/* Sprint badge in nav */
.nav-sprint {
  margin-left: auto;
  font-size: 0.62rem;
  font-weight: 700;
  color: var(--green);
  flex-shrink: 0;
  text-shadow: 0 0 8px var(--green-glow);
}

.nav-divider {
  height: 1px;
  background: var(--border);
  margin: 0.5rem 0.75rem;
}

.sidebar-footer {
  padding: 0.8rem 1rem;
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}
.sidebar-footer a {
  font-size: 0.76rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
.sidebar-footer a:hover { color: var(--text-secondary); text-decoration: none; }

/* ================================================================
   CONTENT AREA
   ================================================================ */
.content-area {
  flex: 1;
  min-width: 0;
  height: 100vh;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}
.content-area::-webkit-scrollbar { width: 5px; }
.content-area::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

.content-inner {
  max-width: 820px;
  margin: 0 auto;
  padding: 2.5rem 3rem 4rem;
}

/* ================================================================
   RIGHT SIDEBAR
   ================================================================ */
.right-sidebar {
  width: var(--right-width);
  flex-shrink: 0;
  height: 100vh;
  overflow-y: auto;
  padding: 2rem 1.25rem 2rem;
  border-left: 1px solid var(--border);
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}
.right-sidebar::-webkit-scrollbar { width: 4px; }
.right-sidebar::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }

.toc-label {
  font-size: 0.64rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 0.8rem;
}
.toc-list { list-style: none; }
.toc-item { margin-bottom: 0.25rem; }
.toc-item a {
  font-size: 0.77rem;
  color: var(--text-secondary);
  line-height: 1.4;
  display: block;
  padding: 0.2rem 0 0.2rem 0.75rem;
  border-left: 2px solid transparent;
  transition: color 0.12s, border-color 0.12s;
}
.toc-item a:hover { color: var(--text-primary); border-left-color: var(--accent); text-decoration: none; }
.toc-item.depth-3 a { padding-left: 1.4rem; font-size: 0.73rem; color: var(--text-muted); }
.toc-item.depth-3 a:hover { color: var(--text-secondary); }

.btn-complete {
  margin-top: 2rem;
  width: 100%;
  padding: 0.6rem 1rem;
  background: transparent;
  color: var(--green);
  border: 1.5px solid var(--green);
  border-radius: 7px;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, box-shadow 0.15s;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  font-family: var(--font);
}
.btn-complete:hover { background: var(--green-dim); box-shadow: 0 0 12px var(--green-glow); }
.btn-complete.done {
  background: var(--green-dim);
  cursor: default;
  pointer-events: none;
}

/* ================================================================
   BREADCRUMB
   ================================================================ */
.breadcrumb {
  font-size: 0.76rem;
  color: var(--text-muted);
  margin-bottom: 1.4rem;
  display: flex;
  align-items: center;
  gap: 0.35rem;
  flex-wrap: wrap;
}
.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--text-secondary); text-decoration: none; }
.breadcrumb .sep { opacity: 0.35; }
.breadcrumb .current { color: var(--text-secondary); }

/* ================================================================
   BADGES
   ================================================================ */
.badges {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 0.9rem;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 0.28rem 0.65rem;
  border-radius: 20px;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  background: var(--card-bg);
}
.badge.blue  { color: var(--accent);  border-color: rgba(79,142,247,0.35);  background: var(--accent-dim); }
.badge.green { color: var(--green);   border-color: rgba(63,185,80,0.35);   background: var(--green-dim); }
.badge.yellow{ color: var(--yellow);  border-color: rgba(210,153,34,0.35);  background: var(--yellow-dim); }

.badge-sprint {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 0.28rem 0.65rem;
  border-radius: 20px;
  color: var(--green);
  border: 1px solid rgba(63,185,80,0.4);
  background: var(--green-dim);
  box-shadow: 0 0 10px var(--green-glow);
}

/* ================================================================
   MARKDOWN CONTENT STYLES
   ================================================================ */
.lesson-content h1 {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 1.5rem;
  line-height: 1.25;
  letter-spacing: -0.025em;
}
.lesson-content h2 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  margin: 2.75rem 0 0.8rem;
  padding-bottom: 0.45rem;
  border-bottom: 1px solid var(--border);
  scroll-margin-top: 1.5rem;
}
.lesson-content h3 {
  font-size: 1.02rem;
  font-weight: 600;
  color: var(--text-primary);
  margin: 2rem 0 0.55rem;
  scroll-margin-top: 1.5rem;
}
.lesson-content h4 {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin: 1.5rem 0 0.4rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.lesson-content p {
  color: var(--text-primary);
  opacity: 0.88;
  margin-bottom: 1.1rem;
  line-height: 1.8;
  font-size: 0.96rem;
}
.lesson-content > p:first-child { font-size: 1.02rem; opacity: 1; }
.lesson-content ul,
.lesson-content ol {
  margin: 0.6rem 0 1.1rem 1.6rem;
}
.lesson-content li {
  color: var(--text-primary);
  opacity: 0.88;
  margin-bottom: 0.45rem;
  line-height: 1.7;
  font-size: 0.96rem;
}
.lesson-content li p { margin-bottom: 0.3rem; }
.lesson-content li > ul,
.lesson-content li > ol { margin-top: 0.35rem; margin-bottom: 0.35rem; }
.lesson-content strong { color: var(--text-primary); font-weight: 600; opacity: 1; }
.lesson-content em { color: var(--text-secondary); }
.lesson-content hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2.5rem 0;
}

/* Blockquote */
.lesson-content blockquote {
  border-left: 3px solid var(--accent);
  margin: 1.25rem 0;
  padding: 0.9rem 1.5rem;
  background: var(--accent-dim);
  border-radius: 0 8px 8px 0;
}
.lesson-content blockquote p { color: var(--text-primary); margin-bottom: 0; font-style: italic; }

/* Code */
.lesson-content code {
  font-family: var(--mono);
  font-size: 0.83em;
  background: var(--card-bg);
  border: 1px solid var(--border);
  padding: 0.14em 0.4em;
  border-radius: 4px;
  color: #e3b341;
}
.lesson-content pre {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 9px;
  padding: 1.25rem 1.5rem;
  overflow-x: auto;
  margin: 1.25rem 0;
}
.lesson-content pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.86rem;
  color: var(--text-primary);
  opacity: 0.9;
}

/* Tables */
.lesson-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.87rem;
  border: 1px solid var(--border);
  border-radius: 9px;
  overflow: hidden;
  display: block;
  overflow-x: auto;
}
.lesson-content th {
  background: var(--card-bg);
  padding: 0.65rem 1rem;
  text-align: left;
  font-weight: 600;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}
.lesson-content td {
  padding: 0.6rem 1rem;
  border-bottom: 1px solid var(--border);
  color: var(--text-primary);
  opacity: 0.88;
  vertical-align: top;
  line-height: 1.55;
}
.lesson-content tr:last-child td { border-bottom: none; }
.lesson-content tbody tr:hover td { background: rgba(255,255,255,0.018); }

/* ================================================================
   LESSON NAVIGATION (prev/next)
   ================================================================ */
.lesson-nav {
  display: flex;
  justify-content: space-between;
  align-items: stretch;
  margin-top: 3.5rem;
  padding-top: 1.75rem;
  border-top: 1px solid var(--border);
  gap: 1rem;
}
.lesson-nav-btn {
  display: flex;
  flex-direction: column;
  padding: 0.85rem 1.25rem;
  border: 1px solid var(--border);
  border-radius: 9px;
  cursor: pointer;
  background: var(--card-bg);
  transition: border-color 0.15s, background 0.15s, transform 0.1s;
  max-width: 47%;
  text-decoration: none;
}
.lesson-nav-btn:hover {
  border-color: var(--accent);
  background: var(--accent-dim);
  transform: translateY(-1px);
  text-decoration: none;
}
.lesson-nav-btn .dir {
  font-size: 0.67rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--text-muted);
  margin-bottom: 0.3rem;
}
.lesson-nav-btn .nav-title {
  font-size: 0.86rem;
  color: var(--text-primary);
  font-weight: 500;
  line-height: 1.35;
}
.lesson-nav-btn.next-btn { margin-left: auto; text-align: right; }

/* ================================================================
   MOBILE HAMBURGER
   ================================================================ */
.hamburger {
  display: none;
  position: fixed;
  top: 0.85rem;
  left: 0.85rem;
  z-index: 200;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 7px;
  width: 36px;
  height: 36px;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-primary);
  font-size: 1rem;
  line-height: 1;
  flex-shrink: 0;
}
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.55);
  z-index: 150;
}

/* ================================================================
   RESPONSIVE
   ================================================================ */
@media (max-width: 1120px) {
  .right-sidebar { display: none; }
}
@media (max-width: 760px) {
  body { overflow: auto; }
  .layout { flex-direction: column; height: auto; min-height: 100vh; overflow: visible; }
  .left-sidebar {
    position: fixed;
    top: 0;
    left: -100%;
    z-index: 160;
    height: 100vh;
    transition: left 0.28s ease;
    width: min(280px, 88vw);
    box-shadow: 4px 0 20px rgba(0,0,0,0.5);
  }
  .left-sidebar.open { left: 0; }
  .sidebar-overlay.open { display: block; }
  .content-area { height: auto; overflow: visible; min-height: 100vh; }
  .content-inner { padding: 4.5rem 1.25rem 3rem; }
  .hamburger { display: flex; }
}

/* ================================================================
   PORTAL PAGE (index.html)
   ================================================================ */
.portal-layout {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--content-bg);
}

.portal-header {
  background: var(--sidebar-bg);
  border-bottom: 1px solid var(--border);
  padding: 1rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: 10;
}
.portal-brand {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-primary);
}

.portal-main {
  flex: 1;
  max-width: 1040px;
  margin: 0 auto;
  padding: 3rem 2rem 5rem;
  width: 100%;
}

.portal-hero {
  margin-bottom: 2.5rem;
}
.portal-hero h1 {
  font-size: 2.4rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--text-primary);
  line-height: 1.2;
  margin-bottom: 0.6rem;
}
.portal-hero p {
  font-size: 1.02rem;
  color: var(--text-secondary);
  max-width: 560px;
  line-height: 1.65;
}

/* Progress card */
.progress-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem 2rem;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 2rem;
  flex-wrap: wrap;
}
.progress-card .big-pct {
  font-size: 2.75rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1;
  flex-shrink: 0;
}
.progress-card .pct-sub {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 0.2rem;
}
.progress-card .bar-wrap { flex: 1; min-width: 160px; }
.progress-card .bar-info {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}
.progress-card .bar-track {
  height: 7px;
  background: var(--border);
  border-radius: 4px;
  overflow: hidden;
}
.progress-card .bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), #79aaff);
  border-radius: 4px;
  transition: width 0.5s ease;
}
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: var(--accent);
  color: #fff;
  padding: 0.7rem 1.5rem;
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  transition: background 0.15s, transform 0.1s;
  flex-shrink: 0;
}
.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
  text-decoration: none;
  transform: translateY(-1px);
}

/* Sprint callout */
.sprint-callout {
  background: var(--green-dim);
  border: 1px solid rgba(63,185,80,0.3);
  border-radius: 10px;
  padding: 1rem 1.5rem;
  margin-bottom: 2.5rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}
.sprint-callout .sprint-icon {
  font-size: 1.4rem;
  flex-shrink: 0;
  text-shadow: 0 0 12px var(--green-glow);
}
.sprint-callout .sprint-text h4 {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--green);
  margin-bottom: 0.2rem;
}
.sprint-callout .sprint-text p {
  font-size: 0.8rem;
  color: var(--text-secondary);
}
.sprint-callout a {
  margin-left: auto;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--green);
  border: 1px solid rgba(63,185,80,0.4);
  padding: 0.4rem 0.9rem;
  border-radius: 6px;
  transition: background 0.12s;
  flex-shrink: 0;
}
.sprint-callout a:hover { background: rgba(63,185,80,0.15); text-decoration: none; }

/* Section headers */
.section-label {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 1rem;
  margin-top: 2.5rem;
}

/* Module grid */
.module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(290px, 1fr));
  gap: 1rem;
}
.module-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.2rem 1.25rem;
  text-decoration: none;
  display: block;
  transition: border-color 0.15s, background 0.15s, transform 0.12s;
  position: relative;
}
.module-card:hover {
  border-color: var(--accent);
  background: var(--card-hover);
  transform: translateY(-2px);
  text-decoration: none;
}
.module-card.completed { border-color: rgba(63,185,80,0.28); }
.module-card.completed:hover { border-color: var(--green); }

.module-card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.7rem;
}
.module-num {
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--text-muted);
}
.module-status {
  width: 20px;
  height: 20px;
  border: 1.5px solid var(--border-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 9px;
  color: transparent;
  transition: all 0.2s;
}
.module-status.done { background: var(--green-dim); border-color: var(--green); color: var(--green); }

.module-card h3 {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.35;
  margin-bottom: 0.4rem;
}
.module-card .module-badges {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
  margin-top: 0.55rem;
}
.module-card .m-badge {
  font-size: 0.66rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--accent);
  background: var(--accent-dim);
  border-radius: 20px;
  padding: 0.18rem 0.55rem;
}
.module-card .m-sprint {
  font-size: 0.66rem;
  font-weight: 700;
  color: var(--green);
  background: var(--green-dim);
  border-radius: 20px;
  padding: 0.18rem 0.55rem;
  text-shadow: 0 0 8px var(--green-glow);
}

/* Bonus row */
.bonus-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.85rem;
}
.bonus-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.1rem 1.2rem;
  text-decoration: none;
  transition: border-color 0.15s, transform 0.12s;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}
.bonus-card:hover { border-color: var(--yellow); transform: translateY(-1px); text-decoration: none; }
.bonus-badge {
  font-size: 0.66rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--yellow);
  margin-bottom: 0.1rem;
}
.bonus-card h4 { font-size: 0.88rem; font-weight: 600; color: var(--text-primary); line-height: 1.3; }

/* Resources section */
.resources-section {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 0.85rem;
}
.resource-group {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  overflow: hidden;
}
.resource-group-header {
  padding: 0.65rem 1rem;
  border-bottom: 1px solid var(--border);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
.resource-group-header .icon { font-size: 0.9rem; }
.resource-list { list-style: none; padding: 0.4rem 0; }
.resource-list li a {
  display: block;
  padding: 0.42rem 1rem;
  font-size: 0.81rem;
  color: var(--text-secondary);
  transition: color 0.12s, background 0.12s;
}
.resource-list li a:hover {
  color: var(--accent);
  background: var(--accent-dim);
  text-decoration: none;
}

/* ================================================================
   LOADING STATE
   ================================================================ */
.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 120px;
  color: var(--text-muted);
  font-size: 0.88rem;
}

/* ================================================================
   PROMISE / CALLOUT BOXES (inside lesson content)
   ================================================================ */
.lesson-content .callout {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.25rem 1.5rem;
  margin: 1.5rem 0;
}
.lesson-content .callout-sprint {
  background: var(--green-dim);
  border: 1px solid rgba(63,185,80,0.3);
  border-radius: 10px;
  padding: 1.25rem 1.5rem;
  margin: 2rem 0;
}