/* ============================================================
   LumoPlans, The Lumo Course
   Reading-optimized layout: hero + two-column shell (reading pane
   on the left, chapter sidebar on the right). At <=900px the sidebar
   becomes a slide-in drawer. Mobile-first, tested from 375px.
   Loads after tokens.css + base.css + pages.css.
   ============================================================ */

/* ---------- Hero ---------- */

.course-hero {
  padding-block: var(--space-7) var(--space-6);
  border-bottom: 1px solid var(--line);
}

.course-hero-title {
  margin-top: var(--space-3);
  font-size: var(--text-3xl);
}
.course-hero-title em { font-style: normal; color: var(--lumo-deep); }

.course-hero-lede {
  margin-top: var(--space-4);
  max-width: 54ch;
  font-size: var(--text-lg);
  color: var(--ink-soft);
}

.course-hero-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: var(--space-5);
}

.course-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: var(--space-5);
}

.course-hero-toc-btn { display: inline-flex; }

@media (min-width: 56.25rem) {
  .course-hero-toc-btn { display: none; }
}

/* ---------- Shell ---------- */

.course-shell {
  display: grid;
  gap: var(--space-6);
  padding-block: var(--space-6) var(--space-8);
  align-items: start;
}

/* Desktop: reading pane + sticky sidebar (RTL-neutral: LTR document) */
@media (min-width: 56.25rem) {
  .course-shell {
    grid-template-columns: minmax(0, 1fr) 19rem;
    gap: var(--space-7);
  }
}

/* ---------- Reading pane ---------- */

.course-pane {
  min-height: 24rem;
  order: 2;
}

@media (min-width: 56.25rem) {
  .course-pane { order: 1; }
}

.course-empty {
  display: grid;
  place-items: center;
  gap: var(--space-4);
  padding-block: var(--space-8);
  text-align: center;
}

.course-spinner {
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 50%;
  border: 3px solid var(--line-strong);
  border-top-color: var(--lumo);
  animation: course-spin 0.8s linear infinite;
}

@keyframes course-spin { to { transform: rotate(360deg); } }

/* ---------- Landing (no chapter selected) ---------- */

.course-landing { display: grid; gap: var(--space-6); }

.course-resume {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-5);
}

.course-resume-title {
  margin-top: var(--space-2);
  font-size: var(--text-xl);
}

.course-resume-meta { margin-top: var(--space-2); font-size: var(--text-sm); }

.course-landing-h { font-size: var(--text-xl); }

.course-cats {
  display: grid;
  gap: var(--space-4);
  grid-template-columns: 1fr;
}

@media (min-width: 34rem) {
  .course-cats { grid-template-columns: 1fr 1fr; }
}

.course-cat {
  display: grid;
  gap: 0.35rem;
  padding: var(--space-5);
  text-align: left;
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  cursor: pointer;
  transition:
    transform var(--speed-fast) var(--ease-out),
    box-shadow var(--speed-fast) var(--ease-out),
    border-color var(--speed-fast) ease;
}

.course-cat:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--line-strong);
}

.course-cat:focus-visible { outline: 2px solid var(--lumo); outline-offset: 3px; }

.course-cat-meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--lumo-deep);
}

.course-cat-title {
  font-family: var(--font-display);
  font-weight: 560;
  font-size: var(--text-lg);
  line-height: var(--leading-snug);
  color: var(--ink);
}

.course-cat-sub { font-size: var(--text-sm); color: var(--muted); }

/* ---------- Chapter view ---------- */

.course-chapter {
  width: min(var(--container-narrow), 100%);
}

.course-chapter-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.course-chapter-kicker {
  margin-top: var(--space-4);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--muted);
}

.course-chapter-title {
  margin-top: var(--space-2);
  font-size: var(--text-2xl);
}

/* ---------- Prose (reading-optimized typography) ---------- */

.course-prose {
  margin-top: var(--space-6);
  font-size: var(--text-lg);
  line-height: var(--leading-body);
  color: var(--ink-soft);
}

.course-prose > * + * { margin-top: var(--space-4); }

.course-prose h1,
.course-prose h2,
.course-prose h3,
.course-prose h4 {
  font-family: var(--font-display);
  color: var(--ink);
}

.course-prose h2 {
  font-size: var(--text-xl);
  margin-top: var(--space-7);
  padding-top: var(--space-4);
  border-top: 1px solid var(--line);
  scroll-margin-top: 5.5rem;
}

.course-prose h3 {
  font-size: var(--text-lg);
  margin-top: var(--space-5);
}

.course-prose h4 {
  font-size: var(--text-base);
  font-weight: 640;
  margin-top: var(--space-5);
}

.course-prose p { max-width: 68ch; }

.course-prose a {
  color: var(--lumo-deep);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}
.course-prose a:hover { color: var(--ink); }

.course-prose strong { color: var(--ink); font-weight: 640; }

.course-prose ul,
.course-prose ol {
  padding-inline-start: 1.35rem;
  display: grid;
  gap: 0.5rem;
  max-width: 68ch;
}

.course-prose li { padding-inline-start: 0.15rem; }

.course-prose blockquote {
  margin-inline: 0;
  padding: var(--space-4) var(--space-5);
  border-inline-start: 3px solid var(--lumo);
  background: var(--lumo-soft);
  border-radius: 0 var(--r-md) var(--r-md) 0;
  color: var(--ink-soft);
}

.course-prose blockquote > * + * { margin-top: var(--space-3); }

.course-prose hr {
  margin-block: var(--space-6);
  border-top: 1px solid var(--line);
}

.course-prose img {
  border-radius: var(--r-md);
  border: 1px solid var(--line);
}

/* Inline code + code blocks, code blocks on --paper-deep well */
.course-prose code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: var(--paper-deep);
  padding: 0.12em 0.4em;
  border-radius: var(--r-sm);
  border: 1px solid var(--line);
}

.course-prose pre {
  background: var(--paper-deep);
  border: 1px solid var(--line-strong);
  border-radius: var(--r-md);
  padding: var(--space-5);
  overflow-x: auto;
  line-height: 1.55;
}

.course-prose pre code {
  background: none;
  border: 0;
  padding: 0;
  font-size: var(--text-sm);
  color: var(--ink);
  white-space: pre;
}

/* Tables */
.prose-table-wrap { overflow-x: auto; max-width: 100%; }

.course-prose table {
  border-collapse: collapse;
  width: 100%;
  font-size: var(--text-sm);
}

.course-prose th,
.course-prose td {
  text-align: left;
  padding: 0.6rem 0.85rem;
  border-bottom: 1px solid var(--line);
}

.course-prose th {
  font-weight: 700;
  color: var(--ink);
  background: var(--paper-deep);
}

.course-prose td { color: var(--ink-soft); }

/* ---------- "Being prepared" / error notice ---------- */

.course-notice {
  display: grid;
  gap: var(--space-3);
  place-items: start;
  padding: var(--space-6);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--paper-raised);
  box-shadow: var(--shadow-sm);
}

.course-notice-icon {
  display: grid;
  place-items: center;
  width: 3rem;
  height: 3rem;
  border-radius: var(--r-md);
  background: var(--lumo-soft);
  color: var(--lumo-deep);
  border: 1px solid rgba(79, 141, 255, 0.22);
}

.course-notice h2 { font-size: var(--text-xl); }
.course-notice p { max-width: 56ch; }

/* ---------- Chapter footer: mark-as-done + nav ---------- */

.course-chapter-foot {
  margin-top: var(--space-7);
  padding-top: var(--space-6);
  border-top: 1px solid var(--line);
  display: grid;
  gap: var(--space-5);
}

.course-done-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  align-self: start;
  min-height: 3rem;
  padding: 0.7rem 1.4rem;
  font: inherit;
  font-weight: 600;
  color: var(--ink);
  background: var(--paper-raised);
  border: 1px solid var(--line-strong);
  border-radius: var(--r-pill);
  cursor: pointer;
  transition:
    transform var(--speed-fast) var(--ease-out),
    background-color var(--speed-fast) ease,
    border-color var(--speed-fast) ease,
    color var(--speed-fast) ease;
}

.course-done-btn:hover { transform: translateY(-2px); border-color: var(--ink); }
.course-done-btn:active { transform: translateY(0); }
.course-done-btn:focus-visible { outline: 2px solid var(--lumo); outline-offset: 3px; }

.course-done-check {
  display: grid;
  place-items: center;
  width: 1.35rem;
  height: 1.35rem;
  border-radius: 50%;
  border: 1.5px solid var(--line-strong);
  color: transparent;
  transition: background-color var(--speed-fast) ease, border-color var(--speed-fast) ease, color var(--speed-fast) ease;
}

.course-done-btn.is-done {
  background: var(--trust-soft);
  border-color: rgba(23, 123, 84, 0.35);
  color: var(--trust);
}

.course-done-btn.is-done .course-done-check {
  background: var(--trust);
  border-color: var(--trust);
  color: var(--paper-raised);
}

.course-navrow {
  display: grid;
  gap: var(--space-4);
  grid-template-columns: 1fr;
}

@media (min-width: 34rem) {
  .course-navrow { grid-template-columns: 1fr 1fr; }
}

.course-navcard {
  display: grid;
  gap: 0.25rem;
  padding: var(--space-4) var(--space-5);
  text-align: left;
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  cursor: pointer;
  transition: transform var(--speed-fast) var(--ease-out), border-color var(--speed-fast) ease, box-shadow var(--speed-fast) ease;
}

.course-navcard:hover { transform: translateY(-3px); border-color: var(--line-strong); box-shadow: var(--shadow-sm); }
.course-navcard:focus-visible { outline: 2px solid var(--lumo); outline-offset: 3px; }
.course-navcard-next { text-align: right; }

.course-navcard.is-empty {
  border: 1px dashed var(--line);
  background: transparent;
  cursor: default;
  pointer-events: none;
}

.course-navcard-dir {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--lumo-deep);
}

.course-navcard-title {
  font-family: var(--font-display);
  font-weight: 560;
  font-size: var(--text-base);
  color: var(--ink);
  line-height: var(--leading-snug);
}

/* ---------- Sidebar ---------- */

.course-sidebar { order: 1; }

@media (min-width: 56.25rem) {
  .course-sidebar {
    order: 2;
    position: sticky;
    top: 5rem;
    align-self: start;
    max-height: calc(100vh - 6rem);
  }
}

.course-sidebar-panel {
  display: flex;
  flex-direction: column;
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
}

@media (min-width: 56.25rem) {
  .course-sidebar-panel { max-height: calc(100vh - 6rem); }
}

.course-sidebar-head {
  padding: var(--space-5);
  border-bottom: 1px solid var(--line);
}

.course-sidebar-head-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-3);
}

.course-progress-label {
  margin-top: 0.35rem;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--ink-soft);
}

.course-progress-track {
  margin-top: var(--space-4);
  height: 0.5rem;
  border-radius: var(--r-pill);
  background: var(--paper-deep);
  overflow: hidden;
}

.course-progress-fill {
  display: block;
  height: 100%;
  width: 0%;
  border-radius: var(--r-pill);
  background: linear-gradient(90deg, var(--lumo), var(--lumo-bright));
  transition: width var(--speed-base) var(--ease-out);
}

/* Close button, only shown in drawer mode */
.course-drawer-close {
  display: none;
  align-items: center;
  justify-content: center;
  width: 2.4rem;
  height: 2.4rem;
  border-radius: var(--r-sm);
  background: transparent;
  border: 1px solid var(--line);
  color: var(--ink-soft);
  cursor: pointer;
}
.course-drawer-close:hover { border-color: var(--ink); color: var(--ink); }
.course-drawer-close:focus-visible { outline: 2px solid var(--lumo); outline-offset: 2px; }

/* Nav / chapter list, scroll region */
.course-nav {
  overflow-y: auto;
  padding: var(--space-3);
  flex: 1;
}

.course-section + .course-section { margin-top: 0.35rem; }

.course-section-head {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.7rem 0.75rem;
  background: transparent;
  border: 0;
  border-radius: var(--r-sm);
  cursor: pointer;
  text-align: left;
  color: var(--ink);
  transition: background-color var(--speed-fast) ease;
}

.course-section-head:hover { background: var(--paper-deep); }
.course-section-head:focus-visible { outline: 2px solid var(--lumo); outline-offset: 2px; }

.course-section-text {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  flex: 1;
  min-width: 0;
}

.course-section-title {
  font-family: var(--font-display);
  font-weight: 560;
  font-size: var(--text-base);
  line-height: var(--leading-snug);
}

.course-section-count {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--muted);
  margin-inline-start: auto;
}

.course-section-chev {
  flex: none;
  color: var(--muted);
  transition: transform var(--speed-base) var(--ease-out);
}

.course-section.is-open .course-section-chev { transform: rotate(180deg); }

.course-section-body {
  display: none;
  padding: 0.15rem 0 0.5rem;
}

.course-section.is-open .course-section-body { display: block; }

/* Chapter item */
.course-chap {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  width: 100%;
  padding: 0.55rem 0.75rem;
  background: transparent;
  border: 0;
  border-radius: var(--r-sm);
  text-align: left;
  cursor: pointer;
  transition: background-color var(--speed-fast) ease;
}

.course-chap:hover { background: var(--paper-deep); }
.course-chap:focus-visible { outline: 2px solid var(--lumo); outline-offset: -2px; }

.course-chap.is-current {
  background: var(--lumo-soft);
}

.course-chap-check {
  flex: none;
  display: grid;
  place-items: center;
  width: 1.15rem;
  height: 1.15rem;
  margin-top: 0.15rem;
  border-radius: 50%;
  border: 1.5px solid var(--line-strong);
  color: transparent;
  transition: background-color var(--speed-fast) ease, border-color var(--speed-fast) ease, color var(--speed-fast) ease;
}

.course-chap.is-done .course-chap-check {
  background: var(--trust);
  border-color: var(--trust);
  color: var(--paper-raised);
}

.course-chap-text { min-width: 0; }

.course-chap-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
}

.course-chap-title {
  display: block;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--ink-soft);
  line-height: var(--leading-snug);
}

.course-chap.is-current .course-chap-title { color: var(--ink); }

.course-sidebar-foot {
  padding: var(--space-4) var(--space-5);
  border-top: 1px solid var(--line);
}

.course-reset-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.4rem 0.2rem;
  background: transparent;
  border: 0;
  color: var(--muted);
  font: inherit;
  font-size: var(--text-sm);
  cursor: pointer;
}

.course-reset-btn:hover { color: var(--danger); }
.course-reset-btn:focus-visible { outline: 2px solid var(--lumo); outline-offset: 2px; border-radius: var(--r-sm); }

/* ---------- Mobile drawer (<=900px) ---------- */

.course-drawer-backdrop { display: none; }

.course-fab {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  position: fixed;
  left: 1rem;
  bottom: 1rem;
  z-index: 90;
  padding: 0.7rem 1.1rem;
  min-height: 3rem;
  background: var(--ink);
  color: var(--paper);
  border: 0;
  border-radius: var(--r-pill);
  box-shadow: var(--shadow-md);
  font: inherit;
  font-weight: 600;
  font-size: var(--text-sm);
  cursor: pointer;
}

.course-fab:focus-visible { outline: 2px solid var(--lumo); outline-offset: 3px; }

.course-fab-count {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--lumo-bright);
}

@media (min-width: 56.25rem) {
  .course-fab { display: none; }
}

/* Below 900px: sidebar slides in from the left as a drawer */
@media (max-width: 56.24rem) {
  .course-sidebar {
    position: fixed;
    inset: 0 auto 0 0;
    z-index: 200;
    width: min(20rem, 88vw);
    max-width: 88vw;
    transform: translateX(-102%);
    transition: transform var(--speed-base) var(--ease-out);
    padding: 0;
  }

  .course-sidebar.is-open { transform: translateX(0); }

  .course-sidebar-panel {
    height: 100%;
    border-radius: 0;
    border: 0;
    border-inline-end: 1px solid var(--line);
    box-shadow: var(--shadow-lg);
  }

  .course-drawer-close { display: inline-flex; }

  .course-drawer-backdrop {
    display: block;
    position: fixed;
    inset: 0;
    z-index: 150;
    background: rgba(20, 23, 42, 0.42);
    -webkit-backdrop-filter: blur(2px);
    backdrop-filter: blur(2px);
  }

  .course-drawer-backdrop[hidden] { display: none; }

  body.course-drawer-lock { overflow: hidden; }
}

@media (prefers-reduced-motion: reduce) {
  .course-sidebar,
  .course-progress-fill,
  .course-section-chev,
  .course-cat,
  .course-navcard,
  .course-done-btn { transition: none; }
  .course-spinner { animation-duration: 0.01ms; }
}