/* ============================================
   KWT Labs — Knowledge Base
   ============================================ */

.kb-shell {
  background: var(--white);
  min-height: 60vh;
}

/* Sticky search bar */
.kb-search-bar {
  position: sticky;
  top: var(--header-h);
  z-index: 90;
  background: var(--white);
  border-bottom: 1px solid var(--gray-200);
  padding: 16px 0;
  box-shadow: 0 2px 8px rgba(15, 23, 42, 0.04);
}

.kb-search-bar__inner {
  display: flex;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
}

.kb-search-bar__brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 0.9375rem;
  color: var(--gray-900);
  white-space: nowrap;
}

.kb-search-bar__brand .icon {
  width: 20px;
  height: 20px;
  color: var(--primary);
}

.kb-search {
  flex: 1;
  min-width: 240px;
  max-width: 640px;
  position: relative;
}

.kb-search__wrap {
  position: relative;
}

.kb-search__icon {
  position: absolute;
  left: 16px;
  top: 50%;
  transform: translateY(-50%);
  pointer-events: none;
}

.kb-search__icon .icon {
  width: 18px;
  height: 18px;
  color: var(--gray-400);
}

.kb-search__input {
  width: 100%;
  padding: 12px 16px 12px 44px;
  font-size: 0.9375rem;
  font-family: var(--font);
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-lg);
  background: var(--gray-50);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.kb-search__input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(15, 111, 255, 0.12);
  background: var(--white);
}

.kb-search__results {
  position: absolute;
  top: calc(100% + 6px);
  left: 0;
  right: 0;
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  max-height: 420px;
  overflow-y: auto;
  z-index: 100;
}

.kb-search__group-label {
  padding: 10px 16px 6px;
  font-size: 0.6875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--gray-400);
  border-top: 1px solid var(--gray-100);
}

.kb-search__group-label:first-child {
  border-top: none;
}

.kb-search__hit {
  display: block;
  padding: 10px 16px;
  color: var(--gray-700);
  border-bottom: 1px solid var(--gray-100);
  transition: background var(--transition);
}

.kb-search__hit:hover {
  background: var(--primary-light);
  color: var(--gray-900);
}

.kb-search__hit strong {
  display: block;
  font-size: 0.875rem;
  color: var(--gray-900);
  margin-bottom: 2px;
}

.kb-search__hit span {
  font-size: 0.75rem;
  color: var(--gray-500);
}

.kb-search__hit--soon {
  opacity: 0.65;
}

.kb-search__empty {
  padding: 16px;
  font-size: 0.875rem;
  color: var(--gray-500);
}

/* Layout */
.kb-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 40px;
  padding: 32px 0 64px;
  align-items: start;
}

.kb-sidebar {
  position: sticky;
  top: calc(var(--header-h) + 80px);
}

.kb-sidebar__label {
  font-size: 0.6875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--gray-400);
  margin-bottom: 10px;
}

.kb-sidebar__label--sub {
  margin-top: 20px;
}

.kb-sidebar__nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.kb-sidebar__link {
  display: block;
  padding: 8px 12px;
  font-size: 0.875rem;
  color: var(--gray-600);
  border-radius: var(--radius-sm);
  transition: background var(--transition), color var(--transition);
}

.kb-sidebar__link:hover,
.kb-sidebar__link.is-active {
  background: var(--primary-light);
  color: var(--primary);
}

.kb-filters {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.kb-sidebar__faq {
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--gray-200);
}

.kb-sidebar__faq .kb-sidebar__link {
  font-weight: 600;
  color: var(--primary);
}

.kb-filter-btn {
  padding: 4px 10px;
  font-size: 0.75rem;
  font-family: var(--font);
  border: 1px solid var(--gray-200);
  border-radius: 999px;
  background: var(--white);
  color: var(--gray-600);
  cursor: pointer;
  transition: all var(--transition);
}

.kb-filter-btn:hover,
.kb-filter-btn.is-active {
  border-color: var(--primary);
  background: var(--primary-light);
  color: var(--primary);
}

.kb-main {
  min-width: 0;
}

.kb-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 0.8125rem;
  color: var(--gray-400);
  margin-bottom: 24px;
}

.kb-breadcrumb a {
  color: var(--gray-500);
}

.kb-breadcrumb a:hover {
  color: var(--primary);
}

/* Homepage hero */
.kb-hero {
  padding: 40px 0 48px;
  border-bottom: 1px solid var(--gray-100);
  margin-bottom: 48px;
}

.kb-hero h1 {
  font-size: clamp(2rem, 4vw, 2.5rem);
  color: var(--gray-900);
  margin-bottom: 12px;
}

.kb-hero__lead {
  font-size: 1.0625rem;
  color: var(--gray-500);
  line-height: 1.75;
  max-width: 600px;
  margin-bottom: 8px;
}

.kb-hero__tagline {
  font-size: 0.875rem;
  color: var(--primary);
  font-weight: 600;
  margin-top: 16px;
}

.kb-hero .kb-search {
  max-width: 100%;
  margin-top: 28px;
}

.kb-hero .kb-search__input {
  padding: 16px 20px 16px 50px;
  font-size: 1rem;
  background: var(--white);
}

.kb-section-block {
  margin-bottom: 56px;
}

.kb-section-block h2 {
  font-size: 1.375rem;
  color: var(--gray-900);
  margin-bottom: 8px;
}

.kb-section-block__desc {
  font-size: 0.9375rem;
  color: var(--gray-500);
  margin-bottom: 24px;
}

/* Cards */
.kb-card-grid {
  display: grid;
  gap: 16px;
}

.kb-card-grid--2 { grid-template-columns: repeat(2, 1fr); }
.kb-card-grid--3 { grid-template-columns: repeat(3, 1fr); }
.kb-card-grid--4 { grid-template-columns: repeat(4, 1fr); }

.kb-topic-card {
  display: flex;
  flex-direction: column;
  padding: 24px;
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.kb-topic-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.kb-topic-card--lg {
  padding: 28px;
}

.kb-topic-card__icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--primary-light);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
}

.kb-topic-card__icon .icon {
  width: 22px;
  height: 22px;
  color: var(--primary);
}

.kb-topic-card h3 {
  font-size: 1.0625rem;
  color: var(--gray-900);
  margin-bottom: 6px;
}

.kb-topic-card p {
  font-size: 0.875rem;
  color: var(--gray-500);
  flex: 1;
}

.kb-topic-card__link {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--primary);
  margin-top: 12px;
}

.kb-article-card {
  display: block;
  padding: 20px;
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-md);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.kb-article-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.kb-article-card__tag {
  display: inline-block;
  font-size: 0.6875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--primary);
  background: var(--primary-light);
  padding: 3px 8px;
  border-radius: 4px;
  margin-bottom: 8px;
}

.kb-article-card h3 {
  font-size: 0.9375rem;
  color: var(--gray-900);
  margin-bottom: 6px;
}

.kb-article-card p {
  font-size: 0.8125rem;
  color: var(--gray-500);
  line-height: 1.5;
}

.kb-product-card {
  padding: 24px;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.kb-product-card h3 {
  font-size: 1.125rem;
  color: var(--gray-900);
}

.kb-product-card__count {
  font-size: 0.8125rem;
  color: var(--gray-500);
}

/* Article page */
.kb-article__header {
  margin-bottom: 32px;
}

.kb-article__header h1 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  color: var(--gray-900);
  margin-bottom: 12px;
}

.kb-article__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.8125rem;
  color: var(--gray-500);
}

.kb-error-badge {
  display: inline-block;
  font-weight: 700;
  color: #b45309;
  background: #fef3c7;
  padding: 2px 10px;
  border-radius: 999px;
  font-size: 0.75rem;
}

.kb-section {
  margin-bottom: 28px;
  padding: 24px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--gray-200);
}

.kb-section h2 {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.kb-section h2 .icon {
  width: 18px;
  height: 18px;
}

.kb-section--problem {
  background: #fef2f2;
  border-color: #fecaca;
}

.kb-section--problem h2 { color: #b91c1c; }

.kb-section--symptoms {
  background: #fffbeb;
  border-color: #fde68a;
}

.kb-section--symptoms h2 { color: #b45309; }

.kb-section--symptoms ul {
  list-style: disc;
  padding-left: 20px;
}

.kb-section--symptoms li {
  font-size: 0.9375rem;
  margin-bottom: 6px;
  color: var(--gray-700);
}

.kb-section--cause {
  background: var(--gray-50);
  border-color: var(--gray-200);
}

.kb-section--cause h2 { color: var(--gray-700); }

.kb-section--resolution {
  background: #ecfdf5;
  border-color: #a7f3d0;
}

.kb-section--resolution h2 { color: #047857; }

.kb-steps {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.kb-steps li {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  font-size: 0.9375rem;
  color: var(--gray-700);
}

.kb-step-num {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--primary);
  color: var(--white);
  font-weight: 700;
  font-size: 0.8125rem;
  border-radius: 50%;
}

.kb-copy-solution {
  margin-top: 16px;
}

.kb-screenshot-placeholder {
  margin: 32px 0;
  padding: 48px 24px;
  background: var(--gray-50);
  border: 2px dashed var(--gray-300);
  border-radius: var(--radius-lg);
  text-align: center;
  color: var(--gray-400);
}

.kb-screenshot-placeholder .icon {
  width: 40px;
  height: 40px;
  margin: 0 auto 12px;
}

.kb-video-placeholder {
  margin: 24px 0;
  padding: 32px;
  background: var(--primary-light);
  border-radius: var(--radius-lg);
  text-align: center;
}

.kb-video-placeholder .icon {
  width: 36px;
  height: 36px;
  color: var(--primary);
  margin: 0 auto 8px;
}

.kb-doc-link {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 16px 20px;
  background: var(--gray-50);
  border-radius: var(--radius-md);
  margin: 24px 0;
  font-size: 0.875rem;
}

.kb-doc-link .icon {
  width: 20px;
  height: 20px;
  color: var(--primary);
  flex-shrink: 0;
  margin-top: 2px;
}

.kb-related {
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--gray-200);
}

.kb-related h2 {
  font-size: 1.125rem;
  margin-bottom: 16px;
}

.kb-helpful {
  margin-top: 40px;
  padding: 24px;
  background: var(--gray-50);
  border-radius: var(--radius-lg);
  text-align: center;
}

.kb-helpful p {
  font-size: 0.9375rem;
  color: var(--gray-600);
  margin-bottom: 12px;
}

.kb-helpful__buttons {
  display: flex;
  justify-content: center;
  gap: 12px;
}

.kb-helpful__btn {
  font-size: 1.5rem;
  padding: 8px 20px;
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-md);
  background: var(--white);
  cursor: pointer;
  transition: border-color var(--transition), transform 0.15s ease;
}

.kb-helpful__btn:hover {
  border-color: var(--primary);
  transform: scale(1.05);
}

.kb-helpful__thanks {
  font-size: 0.875rem;
  color: var(--success);
  font-weight: 600;
}

/* Hub */
.kb-hub-header {
  margin-bottom: 32px;
}

.kb-hub-header h1 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  color: var(--gray-900);
  margin-bottom: 8px;
}

.kb-hub-header__desc {
  color: var(--gray-500);
  font-size: 1rem;
  max-width: 600px;
}

.kb-hub-header__count {
  font-size: 0.8125rem;
  color: var(--gray-400);
  margin-top: 8px;
}

.kb-empty {
  padding: 48px;
  text-align: center;
  background: var(--gray-50);
  border-radius: var(--radius-lg);
}

.kb-empty p {
  color: var(--gray-500);
  margin-bottom: 16px;
}

/* Error codes */
.kb-error-card {
  padding: 24px;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  margin-bottom: 20px;
}

.kb-error-card__code {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--white);
  background: var(--primary);
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 12px;
}

.kb-error-card h3 {
  font-size: 1.125rem;
  color: var(--gray-900);
  margin-bottom: 12px;
}

.kb-error-card dl {
  display: grid;
  gap: 12px;
  font-size: 0.9375rem;
}

.kb-error-card dt {
  font-weight: 700;
  color: var(--gray-700);
}

.kb-error-card dd {
  color: var(--gray-600);
  margin-left: 0;
  line-height: 1.6;
}

.kb-error-card__related {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--gray-200);
  font-size: 0.875rem;
}

.kb-error-card__related a {
  margin-right: 12px;
}

/* Collections, solved, community */
.kb-solved-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 0;
  border-bottom: 1px solid var(--gray-100);
  font-size: 0.875rem;
}

.kb-solved-item__status {
  font-weight: 600;
  color: var(--success);
  font-size: 0.75rem;
}

.kb-community {
  padding: 32px;
  border: 2px dashed var(--gray-300);
  border-radius: var(--radius-lg);
  text-align: center;
  opacity: 0.7;
}

.kb-community h2 {
  font-size: 1.125rem;
  color: var(--gray-500);
  margin-bottom: 8px;
}

.kb-footer-links {
  border-top: 1px solid var(--gray-200);
  padding: 24px 0;
  background: var(--gray-50);
}

.kb-footer-links__inner {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  justify-content: center;
  font-size: 0.875rem;
}

.kb-home--full .kb-layout {
  grid-template-columns: 1fr;
}

.kb-home--full .kb-sidebar {
  display: none;
}

.kb-updated-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.kb-updated-item {
  display: flex;
  justify-content: space-between;
  padding: 12px 0;
  border-bottom: 1px solid var(--gray-100);
  font-size: 0.875rem;
}

.kb-updated-item time {
  color: var(--gray-400);
  font-size: 0.8125rem;
}

/* Filter hidden */
.kb-article-card.is-filtered-out,
.kb-article-card[data-filter-hidden="true"] {
  display: none;
}

/* Responsive */
@media (max-width: 1024px) {
  .kb-card-grid--4 { grid-template-columns: repeat(2, 1fr); }
  .kb-card-grid--3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .kb-layout {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .kb-sidebar {
    position: static;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--gray-200);
  }

  .kb-sidebar__nav {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 6px;
  }

  .kb-sidebar__label--sub {
    width: 100%;
  }

  .kb-filters {
    display: none;
  }

  .kb-card-grid--2,
  .kb-card-grid--3,
  .kb-card-grid--4 {
    grid-template-columns: 1fr;
  }

  .kb-search-bar__brand span:last-child {
    display: none;
  }
}