.lesson-page {
  max-width: 760px;
  margin: 96px auto 80px;
  padding: 0 24px;
  font: 400 16px/1.7 Inter, sans-serif;
  color: var(--text-secondary);
}
.lesson-back {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font: 500 14px/1 Inter, sans-serif;
  color: var(--text-muted);
  text-decoration: none;
  padding: 8px 0;
  margin-bottom: 24px;
  transition: color .15s ease;
}
.lesson-back:hover { color: #10b981; }
[data-theme="light"] .lesson-back:hover { color: #059669; }

.lesson-head { margin-bottom: 32px; }
.lesson-badge {
  display: inline-flex;
  align-items: center;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(245,158,11,0.14);
  color: #f59e0b;
  font: 600 11px/1 Inter, sans-serif;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 14px;
}
[data-theme="light"] .lesson-badge { color: #b45309; }
.lesson-title {
  font: 700 32px/1.25 Onest, Inter, sans-serif;
  margin: 0;
  color: var(--text);
}
.lesson-meta {
  margin: 10px 0 0;
  font: 500 14px/1.5 Inter, sans-serif;
  color: var(--text-muted);
}

.lesson h2 {
  font: 700 22px/1.3 Onest, Inter, sans-serif;
  margin: 36px 0 14px;
  color: var(--text);
}
.lesson h3 {
  font: 600 17px/1.4 Onest, Inter, sans-serif;
  margin: 22px 0 10px;
  color: var(--text);
}
.lesson p { margin: 0 0 14px; }
.lesson ul, .lesson ol {
  margin: 0 0 14px;
  padding-left: 22px;
}
.lesson li { margin: 6px 0; }
.lesson li::marker { color: var(--text-muted); }
.lesson strong { color: var(--text); font-weight: 600; }
.lesson em { color: var(--text); }
.lesson blockquote {
  margin: 18px 0;
  padding: 16px 20px;
  border-left: 3px solid #f59e0b;
  background: var(--bg-secondary);
  border-radius: 0 10px 10px 0;
  font: 500 15.5px/1.65 Inter, sans-serif;
  color: var(--text);
}
.lesson blockquote p { margin: 0 0 8px; }
.lesson blockquote p:last-child { margin: 0; }

.lesson-table-wrap {
  overflow-x: auto;
  margin: 14px 0 22px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--bg-card);
}
.lesson-table {
  width: 100%;
  border-collapse: collapse;
  font: 400 14.5px/1.55 Inter, sans-serif;
}
.lesson-table thead th {
  text-align: left;
  padding: 12px 16px;
  background: var(--bg-secondary);
  color: var(--text-muted);
  font: 600 12px/1.2 Inter, sans-serif;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  border-bottom: 1px solid var(--border);
}
.lesson-table tbody td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  color: var(--text);
  vertical-align: top;
}
.lesson-table tbody tr:last-child td { border-bottom: none; }
.lesson-table tbody td:first-child {
  font-weight: 600;
  color: var(--text);
  width: 38%;
}

.lesson-summary {
  margin: 36px 0 0;
  padding: 22px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 3px solid #f59e0b;
  border-radius: 14px;
}
.lesson-summary h2 { margin-top: 0; }
.lesson-summary ol { margin: 8px 0 0; padding-left: 22px; }
.lesson-summary li { margin: 8px 0; color: var(--text); }

.lesson-next-hint {
  margin: 28px 0 0;
  color: var(--text-muted);
  font-size: 15px;
}

.lesson-nav {
  margin-top: 36px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 12px;
}
.lesson-nav > :nth-child(1) { justify-self: start; }
.lesson-nav > :nth-child(2) { justify-self: center; }
.lesson-nav > :nth-child(3) { justify-self: end; }
.lesson-nav-spacer { display: block; min-height: 1px; }
@media (max-width: 700px) {
  .lesson-nav { grid-template-columns: 1fr; gap: 10px; }
  .lesson-nav > :nth-child(1),
  .lesson-nav > :nth-child(2),
  .lesson-nav > :nth-child(3) { justify-self: stretch; }
  .lesson-nav .lesson-nav-btn { justify-content: center; width: 100%; }
  .lesson-nav-spacer { display: none; }
}
.lesson-nav-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text);
  font: 600 14px/1 Inter, sans-serif;
  text-decoration: none;
  transition: border-color .15s ease, background .15s ease, color .15s ease;
}
.lesson-nav-btn:hover {
  border-color: rgba(245,158,11,0.5);
  background: rgba(245,158,11,0.08);
  color: #f59e0b;
}
[data-theme="light"] .lesson-nav-btn:hover { color: #b45309; border-color: rgba(180,83,9,0.5); }

@media (max-width: 700px) {
  .lesson-page { margin: 72px auto 56px; padding: 0 16px; font-size: 15.5px; }
  .lesson-title { font-size: 24px; }
  .lesson h2 { font-size: 19px; }
  .lesson h3 { font-size: 16px; }
  .lesson-summary { padding: 18px; }
  .lesson-table tbody td:first-child { width: auto; }
}