/* ==========================================================================
   Lesson detail (page-lesson)
   Page-specific rules only; tokens, chrome and shared components in site.css.
   Every selector is scoped under .page-lesson.
   ========================================================================== */

/* --------------------------------------------------------------------------
   Back link
   -------------------------------------------------------------------------- */

.page-lesson .lesson-back {
  padding-top: clamp(26px, 3vw, 40px);
}
.page-lesson .lesson-back-link {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font: 500 12px/1 var(--font-mono);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink3);
}
.page-lesson .lesson-back-link:hover {
  color: var(--ink);
}

/* --------------------------------------------------------------------------
   Flex row: body column + aside. The body flex item carries no max-width
   (the .prose wrapper inside does), or the aside would steal the width.
   -------------------------------------------------------------------------- */

.page-lesson .lesson-page {
  padding: clamp(22px, 2.5vw, 34px) 0 clamp(52px, 6vw, 96px);
}
.page-lesson .lesson-layout {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(28px, 3.2vw, 54px);
  align-items: stretch;
}
.page-lesson .lesson-body {
  flex: 1 1 min(100%, 560px);
  min-width: 0;
}

/* --------------------------------------------------------------------------
   Video embed (16:9 wrapper; hosts a raw stored iframe, a youtube-nocookie
   iframe, or the thumbnail as a still)
   -------------------------------------------------------------------------- */

.page-lesson .lesson-video {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: var(--dark);
  border: 1px solid var(--rule);
  overflow: hidden;
}
.page-lesson .lesson-video iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}
.page-lesson .lesson-video-still {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* --------------------------------------------------------------------------
   Lesson header: mono meta row, H1, lead
   -------------------------------------------------------------------------- */

.page-lesson .lesson-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin-top: clamp(22px, 2.4vw, 32px);
  font: 500 11px/1 var(--font-mono);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink3);
}
.page-lesson .lesson-meta-num {
  color: var(--accent-text);
}
.page-lesson .lesson-title {
  margin: 16px 0 0;
  max-width: 24ch;
  font: 500 clamp(32px, 4vw, 56px)/1.04 var(--font-serif);
  letter-spacing: -0.03em;
  color: var(--ink);
  text-wrap: balance;
}
.page-lesson .lesson-lead {
  margin: 20px 0 0;
  max-width: 62ch;
  font: 400 clamp(18px, 1.5vw, 21px)/1.6 var(--font-sans);
  color: var(--ink2);
  text-wrap: pretty;
}

/* --------------------------------------------------------------------------
   Prose: lesson body opens on an ink rule; lesson h2s run smaller than the
   article scale, and lists render as hairline-ruled rows (no bullets)
   -------------------------------------------------------------------------- */

.page-lesson .lesson-prose {
  margin-top: clamp(30px, 3.4vw, 46px);
  padding-top: clamp(26px, 3vw, 38px);
  border-top: 1px solid var(--ink);
}
.page-lesson .prose p {
  margin: 18px 0 0;
}
.page-lesson .prose h2 {
  margin: clamp(30px, 3vw, 42px) 0 0;
  font: 500 clamp(20px, 2vw, 26px)/1.2 var(--font-serif);
  letter-spacing: normal;
  color: var(--ink);
  /* anchored h2s land below the sticky header (82px) with breathing room */
  scroll-margin-top: 110px;
}
.page-lesson .prose > h2:first-child {
  margin-top: 0;
}
.page-lesson .prose h2 + p {
  margin-top: 14px;
}
.page-lesson .prose ul {
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--rule);
}
.page-lesson .prose ul li {
  margin: 0;
  padding: 12px 0;
  border-bottom: 1px solid var(--rule);
  font: 400 16.5px/1.55 var(--font-sans);
  color: var(--ink2);
}

/* --------------------------------------------------------------------------
   Aside: all-lessons list, navy support block, sticky outline (last child)
   -------------------------------------------------------------------------- */

.page-lesson .lesson-aside {
  flex: 1 1 min(100%, 240px);
  min-width: 0;
  display: grid;
  gap: clamp(20px, 2.2vw, 28px);
  align-content: start;
}
.page-lesson .lesson-aside-label {
  font: 500 10.5px/1 var(--font-mono);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink3);
}

.page-lesson .lesson-toc {
  border: 1px solid var(--rule);
  background: var(--panel);
}
.page-lesson .lesson-toc-head {
  padding: 18px 20px;
  border-bottom: 1px solid var(--rule);
}
.page-lesson .lesson-toc-item {
  display: grid;
  grid-template-columns: 30px 1fr;
  gap: 12px;
  padding: 13px 20px;
  border-bottom: 1px solid var(--rule);
  transition: background-color 0.15s;
}
.page-lesson .lesson-toc-item:last-child {
  border-bottom-color: transparent;
}
.page-lesson .lesson-toc-item:hover {
  background: var(--band);
}
.page-lesson .lesson-toc-num {
  font: 400 11.5px/1.45 var(--font-mono);
  color: var(--ink3);
}
.page-lesson .lesson-toc-title {
  font: 400 14.5px/1.42 var(--font-sans);
  color: var(--ink2);
}
.page-lesson .lesson-toc-item:hover .lesson-toc-title {
  color: var(--ink);
}
.page-lesson .lesson-toc-item.is-current {
  background: var(--band);
}
.page-lesson .lesson-toc-item.is-current .lesson-toc-num {
  color: var(--accent-text);
}
.page-lesson .lesson-toc-item.is-current .lesson-toc-title {
  color: var(--ink);
}

.page-lesson .lesson-support {
  background: var(--dark);
  color: var(--paper);
  padding: 24px;
}
.page-lesson .lesson-support .lesson-aside-label {
  color: var(--accent-soft);
}
.page-lesson .lesson-support p {
  margin: 14px 0 0;
  font: 400 15.5px/1.6 var(--font-sans);
  color: rgba(var(--paper-rgb), 0.86);
}
.page-lesson .lesson-support .btn {
  margin-top: 20px;
  padding: 14px 20px;
  min-height: 46px;
  font-size: 14px;
}

/* Sticky positioning comes from the shared .sticky-aside (top: 96px). */
.page-lesson .lesson-outline {
  border: 1px solid var(--rule);
  background: var(--panel);
  padding: 20px;
}
.page-lesson .lesson-outline-links {
  display: grid;
  gap: 12px;
  margin-top: 16px;
}
.page-lesson .lesson-outline-links a {
  font: 400 14px/1.45 var(--font-sans);
  color: var(--ink2);
}
.page-lesson .lesson-outline-links a:hover {
  color: var(--ink);
}

/* --------------------------------------------------------------------------
   Previous / next band
   -------------------------------------------------------------------------- */

.page-lesson .lesson-pn {
  padding: clamp(40px, 5vw, 72px) 0;
}
.page-lesson .lesson-pn-row {
  display: flex;
  flex-wrap: wrap;
  gap: 18px 32px;
  align-items: center;
  justify-content: space-between;
}
.page-lesson .lesson-pn-link {
  display: grid;
  gap: 8px;
}
.page-lesson .lesson-pn-link--next {
  margin-left: auto;
  text-align: right;
  justify-items: end;
}
.page-lesson .lesson-pn-label {
  font: 500 10.5px/1 var(--font-mono);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink3);
}
.page-lesson .lesson-pn-title {
  font: 500 clamp(19px, 1.8vw, 24px)/1.24 var(--font-serif);
  color: var(--ink);
}
.page-lesson .lesson-pn-link:hover .lesson-pn-title {
  color: var(--accent-text);
}

/* --------------------------------------------------------------------------
   Per-lesson FAQ (band section; accordion styling shared via .faq)
   -------------------------------------------------------------------------- */

.page-lesson .lesson-faq {
  padding: clamp(48px, 5.6vw, 90px) 0;
}
.page-lesson .lesson-faq-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 300px), 1fr));
  gap: clamp(28px, 4vw, 68px);
}
.page-lesson .lesson-faq-title {
  margin: 14px 0 0;
  max-width: 16ch;
  font: 500 clamp(26px, 3.2vw, 42px)/1.06 var(--font-serif);
  letter-spacing: -0.025em;
  color: var(--ink);
}
.page-lesson .lesson-faq-intro {
  margin: 18px 0 0;
  max-width: 42ch;
  font: 400 17px/1.6 var(--font-sans);
  color: var(--ink2);
  text-wrap: pretty;
}
.page-lesson .lesson-faq-cta {
  margin-top: 24px;
}
.page-lesson .lesson-faq-cta .btn {
  padding: 15px 22px;
}
.page-lesson .lesson-faq-list {
  border-top: 1px solid var(--ink);
}