/* =================================================================
   Knowledge hub (knowledge-hub.php)
   Load AFTER css/index.css (tokens, fonts, header, footer).
   ================================================================= */

/* -----------------------------------------------------------------
   HERO — the homepage hero, with the search inside it
   ----------------------------------------------------------------- */
.kh-hero {
  --orb-w: 360px;
  --orb-h: 270px;
  --orb-side: 8%;
  --orb-top: 50%;
  --orb-cx: calc(var(--orb-side) + var(--orb-w) / 2);

  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding: clamp(3rem, 2rem + 5vw, 5.5rem) var(--gutter) !important;
  color: var(--night-soft);
  background:
    radial-gradient(60% 80% at var(--orb-cx) var(--orb-top), rgba(14, 78, 134, 0.3), transparent 70%),
    linear-gradient(160deg, var(--night-surface) 0%, var(--night-panel) 50%, var(--night-page) 100%);
}

.kh-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -2;
  background: repeating-radial-gradient(
    ellipse var(--orb-w) var(--orb-h) at var(--orb-cx) var(--orb-top),
    rgba(255, 255, 255, 0.07) 0 1px,
    transparent 1px 7%
  );
  -webkit-mask-image: radial-gradient(ellipse 60% 100% at var(--orb-cx) var(--orb-top), #000 10%, rgba(0, 0, 0, 0.35) 55%, transparent 85%);
  mask-image: radial-gradient(ellipse 60% 100% at var(--orb-cx) var(--orb-top), #000 10%, rgba(0, 0, 0, 0.35) 55%, transparent 85%);
}

.kh-hero::after {
  content: "";
  position: absolute;
  z-index: -1;
  top: var(--orb-top);
  left: var(--orb-side);
  width: var(--orb-w);
  height: var(--orb-h);
  margin-top: calc(var(--orb-h) / -2);
  pointer-events: none;
  background: radial-gradient(
    ellipse at center,
    rgba(246, 178, 60, 0.7) 0%,
    rgba(224, 154, 30, 0.3) 22%,
    rgba(34, 184, 216, 0.22) 48%,
    transparent 70%
  );
  filter: blur(2px);
}

.kh-hero-inner {
  max-width: var(--container);
  margin: 0 auto;
}

.kh-hero-inner > * {
  max-width: 660px;
}

.kh-crumbs {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 1rem;
  font-size: var(--fs-sm);
  color: var(--night-soft);
}

.kh-crumbs a:hover { color: var(--night-ink); }
.kh-crumbs i { font-size: 0.65em; opacity: 0.7; }
.kh-crumbs [aria-current] { color: var(--night-ink); }

.kh-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 1.4rem + 3vw, 3.4rem);
  font-weight: 700;
  line-height: 1.25;
  color: var(--white);
  margin-bottom: 0.9rem;
}

.kh-hero p {
  font-size: clamp(1rem, 0.9rem + 0.4vw, 1.15rem);
  line-height: 1.9;
  color: var(--night-soft);
  margin-bottom: 1.75rem;
}

/* Search (on the dark hero) */
.kh-search {
  position: relative;
  display: block;
}

.kh-search > i {
  position: absolute;
  z-index: 1;
  right: 1.15rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--night-soft);
  pointer-events: none;
}

.kh-search input {
  width: 100%;
  height: 56px;
  padding: 0 3rem 0 3.25rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--night-line);
  background: rgba(17, 45, 71, 0.75);
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
  color: var(--night-ink);
  font-size: var(--fs-base);
  transition: border-color var(--transition), box-shadow var(--transition), background var(--transition);
}

.kh-search input::placeholder {
  color: var(--night-soft);
  opacity: 0.85;
}

.kh-search input:focus {
  outline: none;
  border-color: var(--lagoon);
  background: rgba(17, 45, 71, 0.95);
  box-shadow: 0 0 0 4px rgba(34, 184, 216, 0.18);
}

.kh-search kbd {
  position: absolute;
  z-index: 1;
  left: 0.9rem;
  top: 50%;
  transform: translateY(-50%);
  min-width: 26px;
  padding: 0.1rem 0.45rem;
  border-radius: 6px;
  border: 1px solid var(--night-line);
  color: var(--night-soft);
  font-family: ui-monospace, monospace;
  font-size: 0.8rem;
  text-align: center;
}

.kh-search input:focus ~ kbd {
  display: none;
}

@media (max-width: 760px) {
  .kh-hero {
    --orb-w: 240px;
    --orb-h: 180px;
    --orb-side: -80px;
    --orb-top: 25%;
  }

  .kh-search kbd {
    display: none;
  }
}

/* -----------------------------------------------------------------
   FILTER BAR
   ----------------------------------------------------------------- */
.kh-body {
  background: var(--foam);
}

.kh-bar {
  max-width: var(--container);
  margin: 0 auto 1.75rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.kh-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.kh-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  min-height: 40px;
  padding: 0 0.95rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--mist);
  background: var(--white);
  color: var(--ink);
  font-size: var(--fs-sm);
  font-weight: 600;
  transition: background var(--transition), border-color var(--transition), color var(--transition);
}

.kh-chip i {
  font-size: 0.85em;
  color: var(--ink-soft);
}

.kh-chip span {
  min-width: 24px;
  padding: 0 0.4rem;
  border-radius: var(--radius-pill);
  background: var(--foam);
  color: var(--ink-soft);
  font-size: var(--fs-xs);
  font-variant-numeric: tabular-nums;
  text-align: center;
}

.kh-chip:hover {
  border-color: var(--ocean);
}

.kh-chip[aria-pressed="true"] {
  background: var(--ocean);
  border-color: var(--ocean);
  color: var(--white);
}

.kh-chip[aria-pressed="true"] i {
  color: inherit;
}

.kh-chip[aria-pressed="true"] span {
  background: rgba(255, 255, 255, 0.18);
  color: var(--white);
}

.kh-count {
  color: var(--ink-soft);
  font-size: var(--fs-sm);
}

/* On phones the chips scroll sideways in one row */
@media (max-width: 760px) {
  .kh-chips {
    flex-wrap: nowrap;
    overflow-x: auto;
    width: 100%;
    padding-bottom: 4px;
    scrollbar-width: none;
  }

  .kh-chips::-webkit-scrollbar {
    display: none;
  }

  .kh-chip {
    flex-shrink: 0;
    white-space: nowrap;
  }
}

/* -----------------------------------------------------------------
   CARDS
   ----------------------------------------------------------------- */
.kh-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 290px), 1fr));
  gap: clamp(1.1rem, 0.8rem + 1vw, 1.75rem);
  max-width: var(--container);
  margin: 0 auto;
}

.kh-card {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border-radius: var(--radius-lg);
  background: var(--white);
  border: 1px solid var(--line-soft);
  box-shadow: var(--shadow-1);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.kh-card[hidden] {
  display: none;
}

.kh-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2);
  border-color: #BFD6E6;
}

.kh-media {
  display: block;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background:
    radial-gradient(120% 90% at 50% 100%, rgba(34, 184, 216, 0.14), transparent 60%),
    var(--foam);
  border-bottom: 1px solid var(--mist);
}

.kh-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.45s ease;
}

.kh-card:hover .kh-media img {
  transform: scale(1.04);
}

.kh-card .card-body {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  padding: 1.1rem 1.25rem 1.25rem;
}

.kh-tag {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.2rem 0.7rem;
  border-radius: var(--radius-pill);
  background: #E3F5FA;
  color: var(--lagoon-ink);
  font-size: var(--fs-xs);
  font-weight: 700;
}

.kh-card .card-title {
  font-family: var(--font-display);
  font-size: 1.08rem;
  font-weight: 700;
  line-height: 1.55;
  color: var(--ocean);
}

.kh-card .card-title a:hover {
  color: var(--lagoon-ink);
}

.kh-card .card-desc {
  flex-grow: 1;
  font-size: var(--fs-sm);
  line-height: 1.85;
  color: var(--ink-soft);
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 3;
  overflow: hidden;
}

.kh-card .card-link a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  min-height: 42px;
  padding: 0 1.1rem;
  border-radius: var(--radius-md);
  background: var(--ocean);
  color: var(--white);
  font-size: var(--fs-sm);
  font-weight: 700;
  transition: background var(--transition);
}

.kh-card .card-link a i {
  font-size: 0.75em;
}

.kh-card .card-link a:hover {
  background: var(--deep);
}

/* Search match highlight */
.kh-card mark {
  background: rgba(246, 178, 60, 0.35);
  color: inherit;
  border-radius: 3px;
  padding: 0 1px;
}

/* Empty state */
.kh-empty {
  max-width: 520px;
  margin: 1rem auto 0;
  padding: 2.5rem 1rem;
  text-align: center;
  color: var(--ink-soft);
  border: 1.5px dashed var(--mist);
  border-radius: var(--radius-lg);
  background: var(--white);
}

.kh-empty[hidden] {
  display: none;
}

.kh-empty > i {
  display: block;
  font-size: 1.6rem;
  margin-bottom: 0.5rem;
  color: var(--ink-faint);
}

.kh-reset {
  margin-top: 1rem;
  min-height: 42px;
  padding: 0 1.2rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--ocean);
  background: var(--white);
  color: var(--ocean);
  font-weight: 700;
}

.kh-reset:hover {
  background: var(--foam);
}