/* ============================================================
   list.css — Course catalogue page
   Tokens: tokens.css   Header: header.css
   Responsive breakpoints: responsive/list.css
   ============================================================ */

/* ── PAGE WRAPPER ────────────────────────────────────────────── */
.catalog-page {
  max-width: 1280px;
  margin: 0 auto;
  padding: 48px 40px 96px;
}

/* ── PAGE HEADER ─────────────────────────────────────────────── */
.catalog-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  padding-bottom: 36px;
  margin-bottom: 32px;
  border-bottom: 1px solid var(--hairline);
}

.catalog-header__eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-soft);
  margin: 0 0 10px;
}

.catalog-header__title {
  font-family: var(--font-serif);
  font-size: clamp(1.75rem, 3.5vw, 2.75rem);
  font-weight: 400;
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--text);
  margin: 0 0 10px;
}

.catalog-header__sub {
  font-size: 14px;
  color: var(--text-soft);
  margin: 0;
  line-height: 1.6;
}

.catalog-header__sub strong { color: var(--text); font-weight: 600; }

.catalog-clear-link {
  margin-left: 6px;
  font-size: 13px;
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--duration) var(--ease);
}
.catalog-clear-link:hover { border-color: var(--accent); }

.catalog-header__count {
  flex-shrink: 0;
  text-align: right;
  line-height: 1.15;
}
.catalog-header__count-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.04em;
}
.catalog-header__count-label {
  font-family: var(--font-mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-soft);
}

/* ── SUBJECT FILTER — pill chips ─────────────────────────────── */
.subject-filter {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.subject-filter__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-soft);
  white-space: nowrap;
  flex-shrink: 0;
}

.subject-filter__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.subject-pill {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 12px;
  border-radius: 20px;
  border: 1px solid var(--hairline-strong);
  background: transparent;
  color: var(--text-soft);
  font-size: 13px;
  font-weight: 500;
  text-decoration: none;
  white-space: nowrap;
  transition: background var(--duration) var(--ease),
              color var(--duration) var(--ease),
              border-color var(--duration) var(--ease);
}

.subject-pill:hover {
  background: var(--surface-raised);
  color: var(--text);
  border-color: var(--text);
}

.subject-pill--active {
  background: var(--text);
  color: var(--surface);
  border-color: var(--text);
  font-weight: 600;
}

.subject-pill--active:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--text-on-accent);
}

.subject-pill__count {
  font-family: var(--font-mono);
  font-size: 10px;
  opacity: 0.65;
}

/* ── COURSE GRID ─────────────────────────────────────────────── */
.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(296px, 1fr));
  gap: 24px;
}

/* ── COURSE CARD ─────────────────────────────────────────────── */
.course-card {
  display: flex;
  flex-direction: column;
  background: var(--surface-raised);
  border: 1px solid var(--hairline);
  border-radius: 6px;
  overflow: hidden;
  transition: box-shadow var(--duration) var(--ease),
              border-color var(--duration) var(--ease),
              transform var(--duration) var(--ease);
}

.course-card:hover {
  border-color: var(--hairline-strong);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.07);
  transform: translateY(-2px);
}

/* THUMBNAIL */
.course-card__thumb-link { display: block; }

.course-card__thumb {
  position: relative;
  aspect-ratio: 16 / 9;
  background: var(--surface-sunken);
  overflow: hidden;
}

.course-card__thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 320ms var(--ease);
}

.course-card:hover .course-card__thumb img {
  transform: scale(1.03);
}

/* BODY */
.course-card__body {
  flex: 1;
  padding: 18px 20px 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* META ROW — subject tag + difficulty badge */
.course-card__meta-row {
  display: flex;
  align-items: center;
  gap: 7px;
  flex-wrap: wrap;
}

.course-card__subject-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  flex-shrink: 0;
}
.course-card__subject-tag:hover { text-decoration: underline; }

/* DIFFICULTY BADGE */
.course-card__badge {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 2px 7px;
  border-radius: 3px;
  line-height: 1.6;
}

.course-card__badge--beginner {
  background: rgba(34, 197, 94, 0.12);
  color: #166534;
}
[data-theme="dark"] .course-card__badge--beginner {
  background: rgba(34, 197, 94, 0.15);
  color: #86efac;
}

.course-card__badge--intermediate {
  background: rgba(234, 179, 8, 0.12);
  color: #854d0e;
}
[data-theme="dark"] .course-card__badge--intermediate {
  background: rgba(234, 179, 8, 0.15);
  color: #fde047;
}

.course-card__badge--advanced {
  background: rgba(180, 54, 28, 0.10);
  color: var(--accent-ink);
}
[data-theme="dark"] .course-card__badge--advanced {
  background: rgba(224, 122, 95, 0.15);
  color: var(--accent);
}

/* TITLE */
.course-card__title {
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 400;
  line-height: 1.3;
  letter-spacing: -0.01em;
  margin: 0;
  color: var(--text);
}

.course-card__title a {
  color: inherit;
  text-decoration: none;
  transition: color var(--duration) var(--ease);
}
.course-card:hover .course-card__title a { color: var(--accent); }

/* DESCRIPTION */
.course-card__desc {
  font-size: 13px;
  line-height: 1.55;
  color: var(--text-soft);
  margin: 0;
  /* clamp to 3 lines */
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 3;
  overflow: hidden;
}

.course-card__desc--placeholder {
  font-style: italic;
  opacity: 0.55;
}

/* STATS */
.course-card__stats {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 5px 8px;
  margin-top: auto;
  padding-top: 6px;
}

.course-card__stat {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-soft);
}

.course-card__stat svg { flex-shrink: 0; }

.course-card__sep {
  font-size: 11px;
  color: var(--hairline-strong);
}

/* CARD FOOTER — CTA */
.course-card__foot {
  padding: 14px 20px 18px;
  border-top: 1px solid var(--hairline);
}

/* ── BUTTONS ─────────────────────────────────────────────────── */
.c-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: var(--tap);
  padding: 0 18px;
  border-radius: var(--radius);
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.01em;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  border: 1px solid transparent;
  transition: background var(--duration) var(--ease),
              color var(--duration) var(--ease),
              border-color var(--duration) var(--ease);
}

.c-btn--primary {
  background: var(--text);
  color: var(--surface);
  border-color: var(--text);
}
.c-btn--primary:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--text-on-accent);
}

.c-btn--secondary {
  background: var(--surface);
  color: var(--text);
  border-color: var(--hairline-strong);
}
.c-btn--secondary:hover {
  border-color: var(--text);
  background: var(--surface-sunken);
}

/* ── EMPTY STATE ─────────────────────────────────────────────── */
.catalog-empty {
  grid-column: 1 / -1;
  padding: 80px 24px;
  text-align: center;
  border: 1px dashed var(--hairline-strong);
  border-radius: 6px;
}

.catalog-empty__head {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 400;
  color: var(--text);
  margin: 0 0 8px;
}

.catalog-empty__body {
  font-size: 14px;
  color: var(--text-soft);
  margin: 0 0 24px;
}

/* ── REDUCED MOTION ──────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  .course-card,
  .course-card__thumb img,
  .subject-pill,
  .catalog-clear-link,
  .c-btn { transition: none !important; }
}