/* ── RESET & BASE ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* Skip link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: #222;
  color: #fff;
  padding: 0.5rem 1rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-size: 0.875rem;
  z-index: 9999;
  text-decoration: none;
}
.skip-link:focus { top: 0; }

:focus-visible {
  outline: 3px solid #2255aa;
  outline-offset: 2px;
}

body {
  font-family: Georgia, 'Times New Roman', serif;
  background: #f5f4f0;
  color: #222;
  min-height: 100vh;
}

/* ── SITE HEADER ── */
.site-header {
  background: #fff;
  border-bottom: 1px solid #ddd;
  padding: 1.25rem 2rem;
  position: sticky;
  top: 0;
  z-index: 200;
}

.site-header h1 {
  font-size: 1.1rem;
  font-weight: normal;
  letter-spacing: 0.03em;
  color: #333;
}

.site-header h1 a {
  text-decoration: none;
  color: inherit;
}

.site-header h1 a:hover {
  color: #2255aa;
}

.site-header h1 span {
  color: #222;
  font-weight: bold;
}

.site-header--nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-header-nav {
  display: flex;
  gap: 1.5rem;
}

.site-header-nav a {
  font-size: 0.875rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #595959;
  text-decoration: none;
  white-space: nowrap;
}

.site-header-nav a:hover {
  color: #2255aa;
  text-decoration: underline;
}

/* ── PAGE NAV (index only) ── */
.page-nav {
  background: #fff;
  border-bottom: 1px solid #ddd;
  padding: 0 2rem;
  display: flex;
  gap: 0;
  position: sticky;
  top: 54px; /* sits below the header */
  z-index: 100;
}

.page-nav a {
  display: inline-block;
  padding: 0.7rem 1.25rem;
  font-size: 0.875rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #595959;
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color 0.15s, border-color 0.15s;
}

.page-nav a:hover,
.page-nav a:focus-visible {
  color: #2255aa;
  border-bottom-color: #2255aa;
  outline: none;
}

/* ── MAIN WRAPPER ── */
main {
  max-width: 1040px;
  margin: 0 auto;
  padding: 2.5rem 1.5rem;
}

/* ── HERO STRIP ── */
.hero-strip {
  display: flex;
  width: 100%;
  height: 210px;
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 2.75rem;
  gap: 3px;
}

.hero-strip img {
  flex: 1;
  width: 0; /* forces equal widths */
  height: 100%;
  object-fit: cover;
  display: block;
}

/* ── PAGE INTRO ── */
.page-intro {
  width: 100%;
  margin-bottom: 2.75rem;
  padding: 1.4rem 1.75rem;
  background: #fff;
  border: 1px solid #ddd;
  border-radius: 4px;
}

.page-intro p {
  font-size: 0.975rem;
  line-height: 1.8;
  color: #333;
  margin: 0;
}

/* ── SECTION LABELS ── */
.section-label {
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #595959;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  margin-bottom: 1.5rem;
}

/* ── SESSION GRID ── */
.session-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(290px, 1fr));
  gap: 1rem;
  margin-bottom: 1rem;
}

/* ── SESSION CARD ── */
.session-card {
  background: #fff;
  border: 1px solid #ddd;
  border-radius: 4px;
  padding: 1.5rem;
  text-decoration: none;
  color: inherit;
  display: block;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.session-card:hover {
  border-color: #aaa;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.session-card:focus-visible {
  border-color: #2255aa;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  outline: 3px solid #2255aa;
  outline-offset: 2px;
}

.session-num {
  font-size: 0.75rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #767676;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.session-card-title {
  font-size: 1.05rem;
  font-weight: bold;
  line-height: 1.3;
  margin-bottom: 0.35rem;
  color: #222;
}

.session-card-date {
  font-size: 0.875rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #595959;
  margin-bottom: 0.75rem;
}

.session-card-desc {
  font-size: 0.875rem;
  color: #444;
  line-height: 1.6;
  font-family: 'Helvetica Neue', Arial, sans-serif;
}

/* ── ARCHIVE EXPLORER LINK CARD ── */
.explorer-link {
  display: block;
  background: #fff;
  border: 1px solid #ddd;
  border-left: 3px solid #2255aa;
  border-radius: 0 4px 4px 0;
  padding: 1.5rem 1.75rem;
  text-decoration: none;
  color: inherit;
  transition: border-color 0.15s, box-shadow 0.15s;
  max-width: 620px;
}

.explorer-link:hover {
  border-color: #2255aa;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.explorer-link:focus-visible {
  outline: 3px solid #2255aa;
  outline-offset: 2px;
}

.explorer-link-title {
  font-size: 1.1rem;
  font-weight: bold;
  color: #2255aa;
  margin-bottom: 0.5rem;
}

.explorer-link-desc {
  font-size: 0.9rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #444;
  line-height: 1.6;
}

/* ── FOOTER ── */
footer {
  text-align: center;
  padding: 2.5rem 1rem;
  font-size: 0.875rem;
  color: #767676;
  font-family: 'Helvetica Neue', Arial, sans-serif;
}

/* ── SESSION PAGE: WRAPPER ── */
.session-page-wrap {
  max-width: 800px;
  margin: 0 auto;
  padding: 2.5rem 1.5rem;
}

/* ── SESSION PAGE: BACK BUTTON ── */
.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.875rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #444;
  text-decoration: none;
  padding: 0.25rem 0;
  margin-bottom: 2rem;
}

.back-btn:hover { color: #2255aa; }

/* ── SESSION PAGE: HEADER ── */
.session-header {
  margin-bottom: 2.25rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid #ddd;
}

.session-page-num {
  font-size: 0.8rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #767676;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.session-page-title {
  font-size: 1.75rem;
  font-weight: bold;
  line-height: 1.25;
  margin-bottom: 0.5rem;
}

.session-page-date {
  font-size: 0.9rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #595959;
}

/* ── SESSION PAGE: CONTENT ── */
.session-content h2 {
  font-size: 0.8rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #595959;
  margin-bottom: 0.75rem;
  margin-top: 2rem;
}

.session-content h2:first-child {
  margin-top: 0;
}

.session-content p {
  font-size: 0.975rem;
  line-height: 1.75;
  color: #333;
  margin-bottom: 1rem;
}

.session-content ul,
.session-content ol {
  margin-left: 1.5rem;
  margin-bottom: 1rem;
}

.session-content li {
  font-size: 0.975rem;
  line-height: 1.75;
  color: #333;
  margin-bottom: 0.3rem;
}

/* Callout box (for assignments, notes) */
.callout {
  background: #fff;
  border: 1px solid #ddd;
  border-left: 3px solid #2255aa;
  border-radius: 0 4px 4px 0;
  padding: 0.875rem 1.25rem;
  margin-top: 1.75rem;
  font-size: 0.9rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #333;
  line-height: 1.6;
}

.callout strong {
  display: block;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #2255aa;
  margin-bottom: 0.35rem;
}

/* Placeholder box */
.placeholder {
  background: #f9f9f7;
  border: 1px dashed #ccc;
  border-radius: 4px;
  padding: 1rem 1.25rem;
  font-size: 0.875rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #999;
  font-style: italic;
  margin-top: 0.5rem;
}

/* ── SESSION PAGE: PREV/NEXT NAV ── */
.session-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid #ddd;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-size: 0.875rem;
}

.session-nav a {
  color: #2255aa;
  text-decoration: none;
}

.session-nav a:hover {
  text-decoration: underline;
}

.session-nav .nav-prev { }
.session-nav .nav-next { }