/* ============================================================
   Begyn AI — Complete Theme System
   Brand Colors (LOCKED — never change):
     Primary Blue:  #1d4ed8 (700) / #1e3a8a (900) / #2563eb (600)
     Primary Light: #3b82f6 (500) / #60a5fa (400) / #93c5fd (300)
     Gold Accent:   #f59e0b / #fbbf24
   ============================================================ */

/* ---------- CSS Custom Properties — Light Mode ---------- */
:root {
  /* Brand primaries — NEVER override */
  --brand-50:  #eff6ff;
  --brand-100: #dbeafe;
  --brand-200: #bfdbfe;
  --brand-300: #93c5fd;
  --brand-400: #60a5fa;
  --brand-500: #3b82f6;
  --brand-600: #2563eb;
  --brand-700: #1d4ed8;
  --brand-800: #1e40af;
  --brand-900: #1e3a8a;
  --brand-950: #172554;
  --gold-400:  #fbbf24;
  --gold-500:  #f59e0b;

  /* Backgrounds */
  --bg-base:       #ffffff;
  --bg-subtle:     #f8fafc;
  --bg-muted:      #f1f5f9;
  --bg-card:       #ffffff;
  --bg-card-hover: #f8fafc;
  --bg-input:      #ffffff;
  --bg-badge:      #eff6ff;

  /* Borders */
  --border-base:   #e2e8f0;
  --border-strong: #cbd5e1;
  --border-brand:  var(--brand-300);

  /* Text */
  --text-primary:   #0f172a;
  --text-secondary: #374151;
  --text-muted:     #6b7280;
  --text-subtle:    #9ca3af;
  --text-on-brand:  #ffffff;

  /* Navigation */
  --nav-bg:        rgba(255,255,255,0.96);
  --nav-border:    #e8edf3;
  --nav-text:      #4b5563;
  --nav-text-hover:var(--brand-700);

  /* Footer */
  --footer-bg:      #0f172a;
  --footer-text:    #94a3b8;
  --footer-heading: #ffffff;

  /* Dropdowns */
  --dropdown-bg:    #ffffff;
  --dropdown-hover: #eff6ff;

  /* Chat widget (home hero) */
  --chat-bg:        #f9fafb;
  --chat-bubble-ai: #ffffff;
  --chat-text-ai:   #374151;
  --chat-border:    #f3f4f6;

  /* Code */
  --code-bg:        #f1f5f9;
  --code-text:      var(--brand-700);

  /* Scrollbar */
  --scrollbar-track: #f1f5f9;
  --scrollbar-thumb: var(--brand-400);

  /* Shadows */
  --shadow-sm:  0 1px 2px 0 rgb(0 0 0/.05);
  --shadow-md:  0 4px 6px -1px rgb(0 0 0/.07), 0 2px 4px -2px rgb(0 0 0/.07);
  --shadow-lg:  0 10px 15px -3px rgb(0 0 0/.08), 0 4px 6px -4px rgb(0 0 0/.08);
  --shadow-xl:  0 20px 25px -5px rgb(0 0 0/.09), 0 8px 10px -6px rgb(0 0 0/.09);

  /* Focus */
  --ring-brand: var(--brand-500);

  /* Theme toggle */
  --toggle-bg:     #f1f5f9;
  --toggle-border: #e2e8f0;
  --toggle-icon:   var(--text-muted);

  /* Section tint used in hero overlays */
  --hero-overlay: rgba(30,58,138,0.85);
}

/* ---------- Dark Mode ---------- */
html.dark {
  /* Backgrounds */
  --bg-base:       #0d1117;
  --bg-subtle:     #161b22;
  --bg-muted:      #1c2333;
  --bg-card:       #1c2333;
  --bg-card-hover: #222d3d;
  --bg-input:      #1c2333;
  --bg-badge:      #1c2333;

  /* Borders */
  --border-base:   #30363d;
  --border-strong: #3d4a5c;
  --border-brand:  var(--brand-700);

  /* Text */
  --text-primary:   #f0f6fc;
  --text-secondary: #c9d1d9;
  --text-muted:     #8b949e;
  --text-subtle:    #6e7681;
  --text-on-brand:  #ffffff;

  /* Navigation */
  --nav-bg:        rgba(13,17,23,0.97);
  --nav-border:    #30363d;
  --nav-text:      #8b949e;
  --nav-text-hover:var(--brand-400);

  /* Footer */
  --footer-bg:      #080d13;
  --footer-text:    #6e7681;
  --footer-heading: #c9d1d9;

  /* Dropdowns */
  --dropdown-bg:    #1c2333;
  --dropdown-hover: #222d3d;

  /* Chat widget */
  --chat-bg:        #161b22;
  --chat-bubble-ai: #1c2333;
  --chat-text-ai:   #c9d1d9;
  --chat-border:    #30363d;

  /* Code */
  --code-bg:        #1c2333;
  --code-text:      var(--brand-400);

  /* Scrollbar */
  --scrollbar-track: #161b22;
  --scrollbar-thumb: var(--brand-600);

  /* Shadows */
  --shadow-sm:  0 1px 2px 0 rgb(0 0 0/.3);
  --shadow-md:  0 4px 6px -1px rgb(0 0 0/.4), 0 2px 4px -2px rgb(0 0 0/.4);
  --shadow-lg:  0 10px 15px -3px rgb(0 0 0/.5), 0 4px 6px -4px rgb(0 0 0/.4);
  --shadow-xl:  0 20px 25px -5px rgb(0 0 0/.6), 0 8px 10px -6px rgb(0 0 0/.5);

  /* Toggle */
  --toggle-bg:     #1c2333;
  --toggle-border: #30363d;
  --toggle-icon:   #8b949e;
}

/* ============================================================
   RESET & BASE
   ============================================================ */
*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  /* Prevent layout shift during theme switch */
  color-scheme: light dark;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background-color: var(--bg-base);
  color: var(--text-primary);
  transition: background-color 0.25s ease, color 0.25s ease;
  min-height: 100vh;
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Poppins', 'Inter', sans-serif;
  color: var(--text-primary);
  line-height: 1.2;
}

/* ============================================================
   SCROLLBAR
   ============================================================ */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--scrollbar-track); }
::-webkit-scrollbar-thumb {
  background: var(--scrollbar-thumb);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover { background: var(--brand-500); }

/* ============================================================
   FOCUS / ACCESSIBILITY
   ============================================================ */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--ring-brand);
  outline-offset: 2px;
  border-radius: 4px;
}

.skip-to-content {
  position: absolute; top: -40px; left: 0;
  background: var(--brand-700); color: #fff;
  padding: 8px 16px; z-index: 9999;
  font-size: 0.875rem; font-weight: 600;
  text-decoration: none; border-radius: 0 0 6px 0;
  transition: top 0.2s;
}
.skip-to-content:focus { top: 0; }

/* ============================================================
   SMOOTH THEME TRANSITIONS
   ============================================================ */
body,
.site-nav,
.site-footer,
.feature-card,
.article-card,
.pricing-card,
.use-case-card,
.testimonial-card,
.faq-item,
.trust-badge,
.form-input,
.mobile-menu,
.nav-dropdown,
.hero-chat-card,
.stat-section,
.section-white,
.section-subtle,
.section-muted {
  transition:
    background-color 0.25s ease,
    border-color 0.2s ease,
    color 0.2s ease,
    box-shadow 0.2s ease;
}

/* ============================================================
   NAVIGATION
   ============================================================ */
.site-nav {
  background: var(--nav-bg);
  border-bottom: 1px solid var(--nav-border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.nav-link {
  color: var(--nav-text);
  transition: color 0.15s ease;
  text-decoration: none;
}
.nav-link:hover { color: var(--nav-text-hover); }

/* Dropdown */
.nav-dropdown {
  background: var(--dropdown-bg);
  border: 1px solid var(--border-base);
  box-shadow: var(--shadow-xl);
}
.nav-dropdown-item {
  color: var(--text-secondary);
  transition: background 0.15s ease, color 0.15s ease;
  text-decoration: none;
  display: block;
}
.nav-dropdown-item:hover {
  background: var(--dropdown-hover);
  color: var(--nav-text-hover);
}

/* Mobile menu */
.mobile-menu {
  background: var(--nav-bg);
  border-top: 1px solid var(--nav-border);
}
.mobile-menu-link {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.15s ease, background 0.15s ease;
  display: block;
}
.mobile-menu-link:hover { color: var(--nav-text-hover); }

/* ============================================================
   THEME TOGGLE BUTTON — polished pill with icon swap
   ============================================================ */
#theme-toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 0.5rem;
  border: 1.5px solid var(--toggle-border);
  background: var(--toggle-bg);
  color: var(--toggle-icon);
  cursor: pointer;
  flex-shrink: 0;
  overflow: hidden;
  transition:
    background-color 0.2s ease,
    border-color 0.2s ease,
    color 0.2s ease,
    transform 0.15s ease,
    box-shadow 0.2s ease;
}
#theme-toggle:hover {
  background: var(--brand-600);
  border-color: var(--brand-600);
  color: #fff;
  transform: scale(1.08);
  box-shadow: 0 0 0 3px rgba(37,99,235,0.25);
}
#theme-toggle:active { transform: scale(0.96); }

/* Icon states — positioned absolutely so they overlap */
#theme-toggle .icon-sun,
#theme-toggle .icon-moon {
  position: absolute;
  font-size: 0.875rem;
  transition: opacity 0.3s ease, transform 0.35s cubic-bezier(0.34,1.56,0.64,1);
  pointer-events: none;
}

/* Light mode: show sun, hide moon */
#theme-toggle .icon-sun  { opacity: 1; transform: rotate(0deg) scale(1); }
#theme-toggle .icon-moon { opacity: 0; transform: rotate(180deg) scale(0.5); }

/* Dark mode: hide sun, show moon */
html.dark #theme-toggle .icon-sun  { opacity: 0; transform: rotate(-180deg) scale(0.5); }
html.dark #theme-toggle .icon-moon { opacity: 1; transform: rotate(0deg) scale(1); }

/* Tooltip */
#theme-toggle::after {
  content: attr(title);
  position: absolute;
  bottom: -2.2rem;
  left: 50%;
  transform: translateX(-50%);
  white-space: nowrap;
  background: var(--text-primary);
  color: var(--bg-base);
  font-size: 0.7rem;
  font-weight: 500;
  padding: 0.2rem 0.5rem;
  border-radius: 0.3rem;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.2s ease 0.5s;
  z-index: 100;
}
#theme-toggle:hover::after { opacity: 1; }

/* ============================================================
   SECTION UTILITIES
   ============================================================ */
.section-white  { background: var(--bg-base); }
.section-subtle { background: var(--bg-subtle); }
.section-muted  { background: var(--bg-muted); }

/* ============================================================
   HERO SECTIONS — brand gradient preserved in both themes
   ============================================================ */
.hero-brand-gradient {
  background: linear-gradient(135deg, #1e3a8a 0%, #1d4ed8 50%, #1e40af 100%);
}

/* ============================================================
   CARDS
   ============================================================ */
/* Feature cards */
.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-base);
  box-shadow: var(--shadow-sm);
}
.feature-card:hover {
  border-color: var(--brand-300);
  box-shadow: var(--shadow-lg);
  background: var(--bg-card-hover);
}
html.dark .feature-card:hover { border-color: var(--brand-600); }

/* Feature icon badges — dark mode tint */
.feature-icon-blue   { background: #eff6ff; color: #1d4ed8; }
.feature-icon-green  { background: #f0fdf4; color: #16a34a; }
.feature-icon-yellow { background: #fefce8; color: #ca8a04; }
.feature-icon-purple { background: #faf5ff; color: #7c3aed; }
.feature-icon-red    { background: #fef2f2; color: #dc2626; }
.feature-icon-indigo { background: #eef2ff; color: #4338ca; }

html.dark .feature-icon-blue   { background: rgba(29,78,216,0.15); color: var(--brand-400); }
html.dark .feature-icon-green  { background: rgba(22,163,74,0.15);  color: #4ade80; }
html.dark .feature-icon-yellow { background: rgba(202,138,4,0.15);  color: #fbbf24; }
html.dark .feature-icon-purple { background: rgba(124,58,237,0.15); color: #c084fc; }
html.dark .feature-icon-red    { background: rgba(220,38,38,0.15);  color: #f87171; }
html.dark .feature-icon-indigo { background: rgba(67,56,202,0.15);  color: #818cf8; }

/* Article / blog cards */
.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-base);
}
.article-card:hover {
  border-color: var(--brand-400);
  box-shadow: var(--shadow-lg);
}

/* Stats */
.stat-box {
  background: var(--bg-muted);
  border: 1px solid var(--border-base);
}

/* Use-case cards */
.use-case-card {
  background: var(--bg-card);
  border: 1px solid var(--border-base);
}
.use-case-card:hover {
  box-shadow: var(--shadow-lg);
  border-color: var(--brand-400);
}

/* Testimonial cards */
.testimonial-card {
  background: var(--bg-subtle);
  border: 1px solid var(--border-base);
}

/* FAQ */
.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-base);
}
.faq-item summary {
  color: var(--text-primary);
  cursor: pointer;
}
.faq-item summary:hover  { color: var(--brand-600); }
html.dark .faq-item summary:hover { color: var(--brand-400); }
.faq-answer { color: var(--text-secondary); }

/* Pricing cards */
.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-base);
}
.pricing-card:hover {
  border-color: var(--brand-400);
  box-shadow: var(--shadow-lg);
}

/* Trust / integration badges */
.trust-badge {
  background: var(--bg-card);
  border: 1px solid var(--border-base);
  color: var(--text-secondary);
}

/* Integration partner logos */
.integration-logo {
  background: var(--bg-card);
  border: 1px solid var(--border-base);
  color: var(--text-secondary);
  transition: border-color 0.2s, box-shadow 0.2s, background 0.25s;
}
.integration-logo:hover {
  border-color: var(--brand-400);
  box-shadow: var(--shadow-md);
  color: var(--brand-600);
}
html.dark .integration-logo:hover { color: var(--brand-400); }

/* ============================================================
   HERO CHAT CARD (homepage) — dark mode aware
   ============================================================ */
.hero-chat-card {
  background: var(--bg-card);
  border: 1px solid var(--border-base);
}
.hero-chat-bg   { background: var(--chat-bg); }
.hero-chat-ai   { background: var(--chat-bubble-ai); color: var(--chat-text-ai); box-shadow: var(--shadow-sm); }
.hero-chat-user { background: var(--brand-100); color: var(--brand-900); }
html.dark .hero-chat-user { background: rgba(29,78,216,0.2); color: var(--brand-300); }

/* ============================================================
   FORMS
   ============================================================ */
.form-input {
  background: var(--bg-input);
  border: 1px solid var(--border-base);
  color: var(--text-primary);
}
.form-input:focus {
  outline: none;
  border-color: var(--brand-500);
  box-shadow: 0 0 0 3px rgba(59,130,246,0.18);
}
.form-input::placeholder { color: var(--text-subtle); }
.form-label { color: var(--text-secondary); font-weight: 500; }

/* ============================================================
   FOOTER
   ============================================================ */
.site-footer {
  background: var(--footer-bg);
}
.footer-heading { color: var(--footer-heading); }
.footer-text    { color: var(--footer-text); }
.footer-link    { text-decoration: none; transition: color 0.15s ease; }
.footer-link:hover { color: #fff; }
.footer-social {
  background: rgba(255,255,255,0.06);
  transition: background 0.2s ease, color 0.2s ease;
}
.footer-social:hover {
  background: var(--brand-700);
  color: #fff;
}

/* ============================================================
   BLOG PROSE
   ============================================================ */
.prose p          { margin-bottom: 1.25rem; color: var(--text-secondary); line-height: 1.75; }
.prose h2         { font-size: 1.5rem; font-weight: 700; color: var(--text-primary); margin: 2rem 0 1rem; font-family: 'Poppins',sans-serif; }
.prose h3         { font-size: 1.25rem; font-weight: 600; color: var(--text-primary); margin: 1.5rem 0 .75rem; }
.prose ul         { list-style: disc; padding-left: 1.5rem; margin-bottom: 1.25rem; }
.prose ul li      { margin-bottom: .5rem; color: var(--text-secondary); }
.prose ol         { list-style: decimal; padding-left: 1.5rem; margin-bottom: 1.25rem; }
.prose ol li      { margin-bottom: .5rem; color: var(--text-secondary); }
.prose strong     { font-weight: 700; color: var(--text-primary); }
.prose pre        { background: #0d1117; color: #e2e8f0; padding: 1.25rem; border-radius: .75rem; overflow-x: auto; margin-bottom: 1.25rem; font-size: .875rem; border: 1px solid var(--border-base); }
.prose code       { background: var(--code-bg); color: var(--code-text); padding: .125rem .375rem; border-radius: .25rem; font-size: .875em; }
.prose blockquote { border-left: 4px solid var(--brand-500); padding-left: 1.25rem; margin: 1.5rem 0; color: var(--text-muted); font-style: italic; }
.prose a          { color: var(--brand-600); text-decoration: underline; transition: color 0.15s; }
.prose a:hover    { color: var(--brand-800); }
html.dark .prose a { color: var(--brand-400); }
html.dark .prose a:hover { color: var(--brand-300); }

/* ============================================================
   GRADIENT TEXT
   ============================================================ */
.gradient-text {
  background: linear-gradient(135deg, #60a5fa, #a78bfa);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ============================================================
   STAT BAND — always brand blue
   ============================================================ */
.stat-band {
  background: linear-gradient(135deg, var(--brand-700) 0%, var(--brand-800) 100%);
}

/* ============================================================
   CTA SECTIONS
   ============================================================ */
.cta-section-dark {
  background: linear-gradient(135deg, #0f172a 0%, #1e3a8a 50%, #0f172a 100%);
}
html.dark .cta-section-dark {
  background: linear-gradient(135deg, #080d13 0%, #172554 50%, #080d13 100%);
}

/* ============================================================
   BADGE / PILL utilities
   ============================================================ */
.badge-brand {
  background: var(--bg-badge);
  color: var(--brand-700);
  border: 1px solid var(--brand-200);
}
html.dark .badge-brand {
  background: rgba(29,78,216,0.15);
  color: var(--brand-300);
  border-color: rgba(29,78,216,0.3);
}

/* ============================================================
   ANIMATIONS
   ============================================================ */
@keyframes fadeIn { from { opacity:0; transform:translateY(6px); } to { opacity:1; transform:translateY(0); } }
@keyframes pulse  { 0%,100% { opacity:1; } 50% { opacity:.5; } }
@keyframes spin   { to { transform: rotate(360deg); } }

main { animation: fadeIn 0.25s ease-out both; }
.animate-pulse { animation: pulse 2s cubic-bezier(.4,0,.6,1) infinite; }
.animate-spin  { animation: spin 1s linear infinite; }

/* ============================================================
   MOBILE MENU
   ============================================================ */
#mobile-menu { transition: all 0.2s ease; }

/* ============================================================
   PRINT
   ============================================================ */
@media print {
  nav, footer, .cta-section, .cta-section-dark { display: none !important; }
  body { background: #fff; color: #000; }
  a { color: #1d4ed8; }
}

/* ============================================================
   RESPONSIVE UTILITIES
   ============================================================ */
@media (max-width: 768px) {
  h1 { font-size: 2rem !important; }
  h2 { font-size: 1.6rem !important; }
}