/* ═══════════════════════════════════════════════════════
   FAQ Page — faq.css
   Matches the API4Trading design system exactly.
═══════════════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800;900&family=JetBrains+Mono:wght@400;500;700&display=swap');

:root {
  --bg-canvas:   #050810;
  --bg-surface:  #0C1120;
  --bg-elevated: #111827;
  --border-light: rgba(255,255,255,0.06);
  --border-hover: rgba(255,255,255,0.12);
  --primary:      #3B82F6;
  --primary-glow: rgba(59,130,246,0.5);
  --accent:       #6366F1;
  --success:      #10B981;
  --warning:      #F59E0B;
  --text-primary:   #F9FAFB;
  --text-secondary: #9CA3AF;
  --text-muted:     #4B5563;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Menlo', 'Courier New', monospace;
  --radius-sm:  6px;
  --radius-md: 12px;
  --radius-lg: 24px;
  --header-h:  64px;
  --sidebar-w: 320px;
}

*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }

html { scroll-behavior: smooth; height: 100%; }

body {
  font-family: var(--font-sans);
  background: var(--bg-canvas);
  color: var(--text-primary);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  height: 100%;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }

/* ─── HEADER ─────────────────────────────────────── */
.faq-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-h);
  background: rgba(5,8,16,0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-light);
  z-index: 1000;
}

.faq-header-inner {
  max-width: 1600px;
  margin: 0 auto;
  padding: 0 32px;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 32px;
}

.faq-logo img { height: 56px; display: block; }

.faq-nav {
  display: flex;
  align-items: center;
  gap: 28px;
  margin-left: 16px;
}

.faq-nav a {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.2s;
}
.faq-nav a:hover,
.faq-nav a.active { color: var(--text-primary); }
.faq-nav a.active { position: relative; }
.faq-nav a.active::after {
  content: '';
  position: absolute;
  bottom: -4px; left: 0; right: 0;
  height: 2px;
  background: var(--primary);
  border-radius: 2px;
}

.faq-header-cta {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn-ghost {
  padding: 8px 20px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-light);
  font-size: 14px;
  font-weight: 600;
  color: var(--text-secondary);
  transition: all 0.2s;
  cursor: pointer;
  background: transparent;
}
.btn-ghost:hover { border-color: var(--border-hover); color: var(--text-primary); }

.btn-primary {
  padding: 8px 20px;
  border-radius: var(--radius-md);
  background: var(--primary);
  font-size: 14px;
  font-weight: 700;
  color: #fff;
  transition: all 0.2s;
  cursor: pointer;
  border: none;
  display: inline-block;
}
.btn-primary:hover { background: #5b96f8; box-shadow: 0 0 20px var(--primary-glow); }

/* Mobile menu */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 20px;
  cursor: pointer;
  margin-left: auto;
}

.mobile-nav {
  display: none;
  flex-direction: column;
  gap: 4px;
  padding: 16px 24px;
  border-top: 1px solid var(--border-light);
  background: var(--bg-canvas);
}
.mobile-nav a {
  padding: 10px 0;
  font-size: 15px;
  font-weight: 500;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-light);
}
.mobile-nav a:last-child { border-bottom: none; }
.mobile-nav a.active { color: var(--primary); }
.mobile-nav.open { display: flex; }

/* ─── LAYOUT ──────────────────────────────────────── */
.faq-layout {
  display: flex;
  height: 100vh;
  padding-top: var(--header-h);
}

/* ─── SIDEBAR ─────────────────────────────────────── */
.faq-sidebar {
  width: var(--sidebar-w);
  flex-shrink: 0;
  height: 100%;
  overflow-y: auto;
  border-right: 1px solid var(--border-light);
  background: var(--bg-canvas);
  position: sticky;
  top: var(--header-h);
}

/* Custom scrollbar for sidebar */
.faq-sidebar::-webkit-scrollbar { width: 4px; }
.faq-sidebar::-webkit-scrollbar-track { background: transparent; }
.faq-sidebar::-webkit-scrollbar-thumb { background: var(--border-hover); border-radius: 4px; }

.faq-sidebar-inner {
  padding: 24px 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* ── Search ── */
.faq-search-wrap {
  position: relative;
  margin-bottom: 4px;
}

.faq-search-icon {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 13px;
  pointer-events: none;
}

.faq-search {
  width: 100%;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 10px 40px 10px 38px;
  font-family: var(--font-sans);
  font-size: 14px;
  color: var(--text-primary);
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.faq-search::placeholder { color: var(--text-muted); }
.faq-search:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59,130,246,0.1);
}
/* Hide browser default clear button */
.faq-search::-webkit-search-cancel-button { display: none; }

.faq-search-clear {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 12px;
  padding: 2px 4px;
  transition: color 0.2s;
}
.faq-search-clear:hover { color: var(--text-primary); }

.faq-match-count {
  font-size: 11px;
  color: var(--text-muted);
  padding: 0 2px;
  min-height: 16px;
  font-family: var(--font-mono);
}

/* ── Nav list ── */
.faq-nav-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-top: 8px;
}

.faq-category-group {
  margin-bottom: 4px;
}

.faq-category-label {
  font-size: 10px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  padding: 16px 10px 6px;
  display: flex;
  align-items: center;
  gap: 8px;
  user-select: none;
}
.faq-category-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border-light);
}

.faq-nav-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 9px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.4;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
  font-family: var(--font-sans);
}
.faq-nav-item:hover {
  background: var(--bg-surface);
  color: var(--text-primary);
}
.faq-nav-item.active {
  background: rgba(59,130,246,0.1);
  color: var(--primary);
}
.faq-nav-item.active .faq-nav-dot {
  background: var(--primary);
  box-shadow: 0 0 6px var(--primary-glow);
}
.faq-nav-item.hidden { display: none; }

.faq-nav-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--text-muted);
  flex-shrink: 0;
  margin-top: 6px;
  transition: background 0.2s, box-shadow 0.2s;
}

/* ─── MAIN CONTENT ────────────────────────────────── */
.faq-main {
  flex: 1;
  height: 100%;
  overflow-y: auto;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 64px 80px;
}

.faq-main::-webkit-scrollbar { width: 4px; }
.faq-main::-webkit-scrollbar-track { background: transparent; }
.faq-main::-webkit-scrollbar-thumb { background: var(--border-hover); border-radius: 4px; }

/* ── Welcome State ── */
.faq-welcome {
  max-width: 600px;
  text-align: center;
  padding-top: 40px;
  animation: fadeUp 0.4s ease;
}

.faq-welcome-icon {
  width: 72px;
  height: 72px;
  margin: 0 auto 32px;
  background: rgba(59,130,246,0.08);
  border: 1px solid rgba(59,130,246,0.15);
  border-radius: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  color: var(--primary);
}

.faq-welcome h1 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 16px;
  background: linear-gradient(135deg, #fff 0%, var(--text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.faq-welcome p {
  color: var(--text-secondary);
  font-size: 16px;
  line-height: 1.7;
  margin-bottom: 40px;
}

.faq-welcome-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
}

.faq-welcome-tag {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: 20px;
  padding: 8px 18px;
  font-size: 13px;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s;
}
.faq-welcome-tag:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(59,130,246,0.05);
}

/* ── Article View ── */
.faq-article {
  max-width: 760px;
  width: 100%;
  animation: fadeUp 0.3s ease;
}

.faq-article-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 32px;
}

.faq-article-category {
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--primary);
  background: rgba(59,130,246,0.08);
  padding: 4px 12px;
  border-radius: 20px;
  border: 1px solid rgba(59,130,246,0.15);
}

.faq-copy-link {
  display: flex;
  align-items: center;
  gap: 7px;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-family: var(--font-sans);
  font-size: 13px;
  padding: 6px 14px;
  cursor: pointer;
  transition: all 0.2s;
}
.faq-copy-link:hover { border-color: var(--border-hover); color: var(--text-primary); }
.faq-copy-link.copied { color: var(--success); border-color: rgba(16,185,129,0.3); }

.faq-article-question {
  font-size: 36px;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 40px;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.faq-article-answer {
  font-size: 17px;
  line-height: 1.8;
  color: var(--text-secondary);
  padding-bottom: 48px;
  border-bottom: 1px solid var(--border-light);
}

/* Rich answer typography */
.faq-article-answer p { margin-bottom: 20px; }
.faq-article-answer p:last-child { margin-bottom: 0; }

.faq-article-answer h2 {
  font-size: 22px;
  font-weight: 700;
  color: var(--text-primary);
  margin: 32px 0 16px;
}

.faq-article-answer h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
  margin: 24px 0 12px;
}

.faq-article-answer strong { color: var(--text-primary); font-weight: 600; }

.faq-article-answer a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
}
.faq-article-answer a:hover { color: #5b96f8; }

.faq-article-answer ul,
.faq-article-answer ol {
  padding-left: 24px;
  margin: 16px 0 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.faq-article-answer li { color: var(--text-secondary); }

.faq-article-answer code {
  font-family: var(--font-mono);
  font-size: 14px;
  background: var(--bg-elevated);
  border: 1px solid var(--border-light);
  padding: 2px 8px;
  border-radius: 4px;
  color: #60a5fa;
}

.faq-article-answer pre {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 24px;
  margin: 20px 0;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-secondary);
}
.faq-article-answer pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: inherit;
}

.faq-article-answer blockquote {
  border-left: 3px solid var(--primary);
  padding: 16px 20px;
  margin: 20px 0;
  background: rgba(59,130,246,0.04);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--text-secondary);
  font-style: italic;
}

/* Tip / Note callouts */
.faq-article-answer .callout {
  display: flex;
  gap: 14px;
  padding: 16px 20px;
  border-radius: var(--radius-md);
  margin: 20px 0;
  font-size: 15px;
}
.faq-article-answer .callout.tip  { background: rgba(16,185,129,0.06); border: 1px solid rgba(16,185,129,0.15); }
.faq-article-answer .callout.info { background: rgba(59,130,246,0.06); border: 1px solid rgba(59,130,246,0.15); }
.faq-article-answer .callout.warn { background: rgba(245,158,11,0.06);  border: 1px solid rgba(245,158,11,0.15); }
.faq-article-answer .callout i { margin-top: 2px; flex-shrink: 0; }
.callout.tip  i { color: var(--success); }
.callout.info i { color: var(--primary); }
.callout.warn i { color: var(--warning); }

/* ── Prev / Next ── */
.faq-article-nav {
  display: flex;
  justify-content: space-between;
  margin-top: 32px;
}

.faq-nav-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 10px 20px;
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s;
}
.faq-nav-btn:hover { border-color: var(--border-hover); color: var(--text-primary); }
.faq-nav-btn:disabled { opacity: 0.3; cursor: not-allowed; }
.faq-nav-btn--next { margin-left: auto; }

/* ── No Results ── */
.faq-no-results {
  text-align: center;
  padding-top: 60px;
  color: var(--text-secondary);
  animation: fadeUp 0.3s ease;
}
.faq-no-results i { font-size: 40px; color: var(--text-muted); margin-bottom: 20px; display: block; }
.faq-no-results h2 { font-size: 22px; margin-bottom: 8px; color: var(--text-primary); }
.faq-no-results p { font-size: 15px; color: var(--text-muted); }

/* ─── FOOTER ──────────────────────────────────────── */
.faq-footer {
  border-top: 1px solid var(--border-light);
  background: var(--bg-canvas);
  padding: 32px;
}

.faq-footer-inner {
  max-width: 1600px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.faq-footer-brand { display: flex; align-items: center; gap: 16px; }

.faq-footer-brand p {
  font-size: 12px;
  color: var(--text-muted);
}

.faq-footer-links {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}
.faq-footer-links a {
  font-size: 13px;
  color: var(--text-secondary);
  transition: color 0.2s;
}
.faq-footer-links a:hover { color: var(--text-primary); }

.faq-footer-copy {
  font-size: 12px;
  color: var(--text-muted);
}

/* ─── ANIMATIONS ──────────────────────────────────── */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ─── HIGHLIGHT MATCH ─────────────────────────────── */
mark.faq-highlight {
  background: rgba(59,130,246,0.25);
  color: var(--primary);
  border-radius: 2px;
  padding: 0 1px;
}

/* ─── RESPONSIVE ──────────────────────────────────── */
@media (max-width: 1024px) {
  .faq-main { padding: 48px 48px; }
}

@media (max-width: 768px) {
  :root { --sidebar-w: 260px; }
  .faq-nav, .faq-header-cta { display: none; }
  .mobile-menu-btn { display: block; }

  .faq-layout { position: relative; }

  .faq-sidebar {
    position: fixed;
    top: var(--header-h);
    left: 0;
    bottom: 0;
    z-index: 500;
    transform: translateX(-100%);
    transition: transform 0.3s cubic-bezier(0.16,1,0.3,1);
    box-shadow: 4px 0 30px rgba(0,0,0,0.5);
  }
  .faq-sidebar.open { transform: translateX(0); }

  .faq-main {
    width: 100%;
    padding: 32px 24px;
  }

  .faq-article-question { font-size: 26px; }
  .faq-article-answer { font-size: 15px; }

  .faq-footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }
  .faq-logo img { height: 42px; }
}

@media (max-width: 480px) {
  .faq-main { padding: 24px 16px; }
  .faq-article-question { font-size: 22px; }
  .faq-article-nav { flex-direction: column; gap: 10px; }
  .faq-nav-btn--next { margin-left: 0; }
}