/* Knowledge Base — Premium Styles */
:root {
  --kb-primary: var(--primary-color);
  --kb-primary-dark: var(--primary-dark);
  --kb-primary-light: var(--primary-light);
  --kb-primary-gradient: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-light) 100%);
  --kb-text: #0f172a;
  --kb-text-light: #64748b;
  --kb-text-muted: #94a3b8;
  --kb-bg: #f8fafc;
  --kb-bg-white: #ffffff;
  --kb-border: #e2e8f0;
  --kb-border-light: #f1f5f9;
  --kb-shadow: 0 1px 3px rgba(0,0,0,0.04), 0 4px 12px rgba(0,0,0,0.06);
  --kb-shadow-lg: 0 4px 8px rgba(0,0,0,0.04), 0 16px 40px rgba(0,0,0,0.08);
  --kb-radius: 12px;
  --kb-radius-lg: 20px;
  --kb-transition: all 0.3s var(--easing);
}

/* Dark Mode Variables */
[data-theme="dark"] {
  --kb-text: #e2e8f0;
  --kb-text-light: #94a3b8;
  --kb-text-muted: #64748b;
  --kb-bg: #0f172a;
  --kb-bg-white: #1e293b;
  --kb-border: #334155;
  --kb-border-light: #1e293b;
  --kb-shadow: 0 1px 3px rgba(0,0,0,0.2), 0 4px 12px rgba(0,0,0,0.25);
  --kb-shadow-lg: 0 4px 8px rgba(0,0,0,0.2), 0 16px 40px rgba(0,0,0,0.35);
}

/* Reset & Base */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Outfit', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  line-height: var(--leading-relaxed);
  color: var(--kb-text);
  background: var(--kb-bg);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

[data-theme="dark"] body {
  background: linear-gradient(160deg, #0f172a 0%, #1a1f36 40%, #0f172a 100%);
}

/* ---- Top Bar ---- */
.kb-topbar {
  background: var(--kb-bg-white);
  border-bottom: 1px solid var(--kb-border);
  padding: var(--space-3) var(--space-6);
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

[data-theme="dark"] .kb-topbar {
  background: rgba(30, 41, 59, 0.92);
}

.kb-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--kb-text);
  font-weight: 700;
  font-size: var(--text-lg);
}

.kb-logo i {
  color: var(--kb-primary);
  font-size: var(--text-xl);
}

.kb-topbar-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.kb-lang-switch {
  display: flex;
  gap: var(--space-1);
  background: var(--kb-border-light);
  padding: 3px;
  border-radius: var(--radius-sm);
}

[data-theme="dark"] .kb-lang-switch {
  background: #334155;
}

.kb-lang-btn {
  padding: 6px 14px;
  border: none;
  background: transparent;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-weight: 600;
  font-size: var(--text-sm);
  color: var(--kb-text-light);
  cursor: pointer;
  transition: var(--kb-transition);
}

.kb-lang-btn.active {
  background: var(--kb-bg-white);
  color: var(--kb-primary);
  box-shadow: 0 1px 4px rgba(0,0,0,0.08);
}

[data-theme="dark"] .kb-lang-btn.active {
  background: var(--text-light);
  color: var(--accent-amber);
}

.kb-theme-toggle {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  border: 1px solid var(--kb-border);
  background: var(--kb-bg-white);
  color: var(--kb-text);
  font-size: var(--text-base);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--kb-transition);
}

@media (hover: hover) {
  .kb-theme-toggle:hover {
    border-color: var(--kb-primary);
    color: var(--kb-primary);
  }
}

[data-theme="dark"] .kb-theme-toggle {
  background: #334155;
  border-color: var(--text-light);
  color: var(--accent-amber);
}

/* ---- Hero Section ---- */
.kb-hero {
  background: var(--kb-primary-gradient);
  color: var(--text-on-dark);
  padding: var(--space-16) var(--space-6) 56px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.kb-hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -30%;
  width: 80%;
  height: 200%;
  background: radial-gradient(circle, rgba(255,255,255,0.12) 0%, transparent 60%);
  pointer-events: none;
}

.kb-hero h1 {
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  font-weight: 800;
  margin-bottom: var(--space-3);
  letter-spacing: -0.02em;
  position: relative;
}

.kb-hero p {
  font-size: var(--text-lg);
  opacity: 0.92;
  max-width: 540px;
  margin: 0 auto var(--space-8);
  position: relative;
}

/* Search Box */
.kb-search-wrapper {
  max-width: 520px;
  margin: 0 auto;
  position: relative;
}

.kb-search-wrapper i.fa-search {
  position: absolute;
  left: 20px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--kb-text-muted);
  font-size: var(--text-base);
  z-index: 2;
}

.kb-search-input {
  width: 100%;
  padding: var(--space-4) var(--space-5) var(--space-4) 50px;
  border: none;
  border-radius: var(--radius-full);
  font-size: var(--text-base);
  font-family: inherit;
  background: var(--kb-bg-white);
  color: var(--kb-text);
  box-shadow: 0 4px 20px rgba(0,0,0,0.12);
  outline: none;
  transition: var(--kb-transition);
}

.kb-search-input:focus-visible {
  box-shadow: 0 4px 24px rgba(0,0,0,0.16), 0 0 0 3px rgba(255,255,255,0.4);
}

[data-theme="dark"] .kb-search-input {
  background: var(--bg-dark-surface);
  color: var(--text-dark-body);
}

.kb-search-input::placeholder {
  color: var(--kb-text-muted);
}

/* ---- Content Container ---- */
.kb-container {
  max-width: 880px;
  margin: 0 auto;
  padding: var(--space-10) var(--space-6) var(--space-20);
}

/* ---- Category Section ---- */
.kb-category {
  margin-bottom: var(--space-8);
}

.kb-category-header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-3);
  border-bottom: 2px solid var(--kb-border);
}

.kb-category-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius);
  background: var(--kb-primary-gradient);
  color: var(--text-on-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-lg);
  flex-shrink: 0;
}

.kb-category-header h2 {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--kb-text);
  margin: 0;
}

/* ---- Accordion ---- */
.kb-accordion {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.kb-accordion-item {
  background: var(--kb-bg-white);
  border: 1px solid var(--kb-border);
  border-radius: var(--kb-radius);
  overflow: hidden;
  transition: var(--kb-transition);
}

@media (hover: hover) {
  .kb-accordion-item:hover {
    border-color: var(--kb-primary-light);
    box-shadow: var(--kb-shadow);
  }
}

.kb-accordion-item.active {
  border-color: var(--kb-primary);
  box-shadow: 0 2px 12px rgba(255, 49, 49, 0.08);
}

.kb-accordion-trigger {
  width: 100%;
  padding: var(--space-4) var(--space-5);
  border: none;
  background: transparent;
  text-align: left;
  font-family: inherit;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--kb-text);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-3);
  transition: var(--kb-transition);
}

@media (hover: hover) {
  .kb-accordion-trigger:hover {
    color: var(--kb-primary);
  }
}

.kb-accordion-trigger:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
  box-shadow: var(--primary-focus-ring);
}

.kb-accordion-trigger i.fa-chevron-down {
  font-size: var(--text-xs);
  color: var(--kb-text-muted);
  transition: transform 0.3s ease;
  flex-shrink: 0;
}

.kb-accordion-item.active .kb-accordion-trigger i.fa-chevron-down {
  transform: rotate(180deg);
  color: var(--kb-primary);
}

.kb-accordion-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
}

.kb-accordion-item.active .kb-accordion-content {
  max-height: 600px;
}

.kb-accordion-body {
  padding: 0 var(--space-5) var(--space-5);
  font-size: var(--text-sm);
  line-height: var(--leading-relaxed);
  color: var(--kb-text-light);
  hanging-punctuation: first last;
}

.kb-accordion-body p {
  margin-bottom: var(--space-3);
  text-wrap: pretty;
}

.kb-accordion-body ul,
.kb-accordion-body ol {
  padding-left: var(--space-5);
  margin-bottom: var(--space-3);
}

.kb-accordion-body li {
  margin-bottom: 6px;
}

.kb-accordion-body strong {
  color: var(--kb-text);
}

.kb-accordion-body code {
  background: var(--kb-border-light);
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
}

[data-theme="dark"] .kb-accordion-body code {
  background: #334155;
}

/* ---- No Results ---- */
.kb-no-results {
  text-align: center;
  padding: var(--space-12) var(--space-5);
  color: var(--kb-text-muted);
  display: none;
}

.kb-no-results.visible {
  display: block;
}

.kb-no-results i {
  font-size: var(--text-5xl);
  margin-bottom: var(--space-4);
  opacity: 0.4;
}

.kb-no-results h3 {
  font-size: var(--text-xl);
  color: var(--kb-text-light);
  margin-bottom: var(--space-2);
}

/* ---- Footer ---- */
.kb-footer {
  text-align: center;
  padding: var(--space-8) var(--space-6);
  color: var(--kb-text-muted);
  font-size: var(--text-sm);
  border-top: 1px solid var(--kb-border);
  margin-top: var(--space-8);
}

.kb-footer a {
  color: var(--kb-primary);
  text-decoration: none;
  font-weight: 600;
}

@media (hover: hover) {
  .kb-footer a:hover {
    text-decoration: underline;
  }
}

/* ---- Back to Top ---- */
.kb-back-to-top {
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 44px;
  height: 44px;
  border-radius: var(--radius-full);
  border: none;
  background: var(--kb-primary-gradient);
  color: var(--text-on-dark);
  font-size: var(--text-base);
  cursor: pointer;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 16px rgba(255,49,49,0.3);
  transition: var(--kb-transition);
  opacity: 0;
  pointer-events: none;
  transform: translateY(16px);
}

.kb-back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

@media (hover: hover) {
  .kb-back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 24px rgba(255,49,49,0.4);
  }
}

/* ---- Quick Links ---- */
.kb-quick-links {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: var(--space-3);
  margin-bottom: var(--space-10);
}

.kb-quick-link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-4);
  background: var(--kb-bg-white);
  border: 1px solid var(--kb-border);
  border-radius: var(--kb-radius);
  text-decoration: none;
  color: var(--kb-text);
  font-weight: 600;
  font-size: var(--text-sm);
  transition: var(--kb-transition);
}

@media (hover: hover) {
  .kb-quick-link:hover {
    border-color: var(--kb-primary);
    box-shadow: var(--kb-shadow);
    transform: translateY(-2px);
    color: var(--kb-primary);
  }
}

.kb-quick-link i {
  font-size: var(--text-lg);
  color: var(--kb-primary);
}

/* ---- Responsive ---- */
@media (max-width: 640px) {
  .kb-hero {
    padding: var(--space-12) var(--space-4) var(--space-10);
  }

  .kb-hero h1 {
    font-size: var(--text-2xl);
  }

  .kb-container {
    padding: var(--space-6) var(--space-4) 60px;
  }

  .kb-quick-links {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-2);
  }

  .kb-quick-link {
    font-size: var(--text-xs);
    padding: var(--space-3);
  }

  .kb-accordion-trigger {
    padding: var(--space-4) var(--space-4);
    font-size: var(--text-sm);
  }

  .kb-accordion-body {
    padding: 0 var(--space-4) var(--space-4);
    font-size: var(--text-sm);
  }

  .kb-topbar {
    padding: var(--space-3) var(--space-4);
  }
}