/* ==========================================================================
   CAUSE AI — Applied AI, Autonomous Agents & RAG Architecture Stylesheet
   ========================================================================== */

:root {
  --bg-canvas: #070910;
  --bg-surface: #0c101d;
  --bg-surface-elevated: #11172a;
  --bg-glass: rgba(12, 16, 29, 0.85);
  --border-hairline: rgba(59, 130, 246, 0.15);
  --border-active: rgba(59, 130, 246, 0.38);
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent-primary: #3b82f6;
  --accent-glow: rgba(59, 130, 246, 0.22);
  --accent-secondary: #2563eb;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  --container-max: 1220px;
}

[data-theme="light"] {
  --bg-canvas: #f8fafc;
  --bg-surface: #ffffff;
  --bg-surface-elevated: #eff6ff;
  --bg-glass: rgba(255, 255, 255, 0.9);
  --border-hairline: rgba(59, 130, 246, 0.2);
  --border-active: rgba(59, 130, 246, 0.45);
  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;
  --accent-primary: #2563eb;
  --accent-glow: rgba(37, 99, 235, 0.12);
}

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

html {
  font-family: var(--font-sans);
  color: var(--text-primary);
  background-color: var(--bg-canvas);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 85% 15%, var(--accent-glow) 0%, transparent 45%),
    linear-gradient(rgba(59, 130, 246, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(59, 130, 246, 0.03) 1px, transparent 1px);
  background-size: 100% 100%, 48px 48px, 48px 48px;
}

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

/* ==========================================================================
   TOPBAR
   ========================================================================== */
.topbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-glass);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-hairline);
  padding: 14px 0;
}

.topbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-primary);
}

.brand-logo {
  width: 32px;
  height: 32px;
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-weight: 700;
  font-size: 16px;
  letter-spacing: -0.02em;
  line-height: 1.1;
}

.brand-tag {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  color: var(--accent-primary);
  text-transform: uppercase;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 13.5px;
  font-weight: 500;
  transition: color 0.15s ease;
}

.nav-links a:hover {
  color: var(--text-primary);
}

.topbar-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  font-size: 12.5px;
  font-weight: 500;
  border-radius: 999px;
  border: 1px solid var(--border-hairline);
  background: var(--bg-surface);
  color: var(--text-secondary);
  text-decoration: none;
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-pill:hover {
  border-color: var(--border-active);
  color: var(--text-primary);
}

.btn-lang {
  font-family: var(--font-mono);
  font-size: 11px;
}

.theme-toggle-btn {
  background: transparent;
  border: 1px solid var(--border-hairline);
  color: var(--text-secondary);
  width: 32px;
  height: 32px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

/* Floating WhatsApp badge */
.floating-whatsapp {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 90;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 18px;
  border-radius: 999px;
  background: #25d366;
  color: #ffffff;
  text-decoration: none;
  font-weight: 600;
  font-size: 13.5px;
  box-shadow: 0 8px 24px rgba(37, 211, 102, 0.35);
  transition: transform 0.2s ease;
}

.floating-whatsapp:hover {
  transform: translateY(-2px);
}

/* ==========================================================================
   HERO
   ========================================================================== */
.hero {
  padding: 80px 0 60px;
}

.hero-meta {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 4px 12px;
  border-radius: 6px;
  border: 1px solid var(--border-hairline);
  background: var(--bg-surface);
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent-primary);
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(32px, 5vw, 52px);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.035em;
  max-width: 980px;
  margin-bottom: 20px;
}

.accent-text {
  color: var(--accent-primary);
}

.hero-desc {
  font-size: clamp(16px, 2vw, 19px);
  color: var(--text-secondary);
  max-width: 780px;
  line-height: 1.6;
  margin-bottom: 32px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 8px;
  background: var(--accent-primary);
  color: #ffffff;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: transform 0.15s ease, background 0.15s ease;
}

.btn-primary:hover {
  background: var(--accent-secondary);
  transform: translateY(-1px);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 8px;
  background: var(--bg-surface);
  border: 1px solid var(--border-hairline);
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.15s ease;
}

.btn-secondary:hover {
  border-color: var(--border-active);
  background: var(--bg-surface-elevated);
}

/* ==========================================================================
   SERVICES GRID (9 AI SERVICES)
   ========================================================================== */
.services-section {
  padding: 60px 0 80px;
}

.section-head {
  margin-bottom: 36px;
}

.section-kicker {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--accent-primary);
  text-transform: uppercase;
  margin-bottom: 8px;
}

.section-title {
  font-size: 30px;
  font-weight: 700;
  letter-spacing: -0.025em;
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 22px;
}

.service-card {
  position: relative;
  background: var(--bg-surface);
  border: 1px solid var(--border-hairline);
  border-radius: 12px;
  padding: 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all 0.2s ease;
}

.service-card:hover {
  transform: translateY(-2px);
  border-color: var(--border-active);
  box-shadow: 0 8px 24px rgba(59, 130, 246, 0.08);
}

.service-icon-box {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-primary);
  margin-bottom: 20px;
}

.service-title {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.service-desc {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
  flex: 1;
}

.service-cta-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--accent-primary);
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
  transition: gap 0.15s ease;
}

.service-cta-link:hover {
  gap: 10px;
}

/* ==========================================================================
   INTERACTIVE ARCHITECTURE BLUEPRINT
   ========================================================================== */
.blueprint-section {
  padding: 60px 0 80px;
  border-top: 1px solid var(--border-hairline);
}

.blueprint-tabs {
  display: flex;
  gap: 10px;
  margin-bottom: 24px;
  overflow-x: auto;
  padding-bottom: 4px;
}

.blueprint-tab-btn {
  padding: 10px 18px;
  border-radius: 8px;
  border: 1px solid var(--border-hairline);
  background: var(--bg-surface);
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.15s ease;
}

.blueprint-tab-btn.active, .blueprint-tab-btn:hover {
  background: var(--accent-primary);
  color: #ffffff;
  border-color: var(--accent-primary);
}

.blueprint-box {
  background: var(--bg-surface);
  border: 1px solid var(--border-hairline);
  border-radius: 14px;
  padding: 32px;
}

.blueprint-diagram {
  background: var(--bg-canvas);
  border: 1px solid var(--border-hairline);
  border-radius: 10px;
  padding: 24px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.8;
  margin-bottom: 20px;
}

.blueprint-step {
  display: inline-block;
  padding: 4px 10px;
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.25);
  border-radius: 6px;
  color: var(--accent-primary);
}

/* ==========================================================================
   CONTACT CALLOUT
   ========================================================================== */
.contact-banner {
  margin: 30px 0 80px;
  background: var(--bg-surface);
  border: 1px solid var(--border-active);
  border-radius: 14px;
  padding: 40px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.contact-banner-text h3 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 8px;
}

.contact-banner-text p {
  color: var(--text-secondary);
  font-size: 14.5px;
}

.contact-banner-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

/* ==========================================================================
   SEO GUIDE ACCORDIONS
   ========================================================================== */
.guide-section {
  padding: 60px 0 80px;
  border-top: 1px solid var(--border-hairline);
}

.accordion-group {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.guide-accordion {
  border: 1px solid var(--border-hairline);
  border-radius: 10px;
  background: var(--bg-surface);
  overflow: hidden;
  transition: border-color 0.15s ease;
}

.guide-accordion[open] {
  border-color: var(--border-active);
}

.guide-accordion summary {
  padding: 18px 22px;
  font-weight: 700;
  font-size: 16px;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.guide-accordion summary::-webkit-details-marker {
  display: none;
}

.guide-accordion summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--accent-primary);
}

.guide-accordion[open] summary::after {
  content: "−";
}

.guide-content {
  padding: 0 24px 24px;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.7;
}

/* Footer */
.footer {
  border-top: 1px solid var(--border-hairline);
  padding: 40px 0;
  font-size: 13px;
  color: var(--text-muted);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
}

.footer-nav {
  display: flex;
  gap: 20px;
}

.footer-nav a {
  color: var(--text-secondary);
  text-decoration: none;
}

.footer-nav a:hover {
  color: var(--text-primary);
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  .services-grid {
    grid-template-columns: 1fr;
  }
  .contact-banner {
    padding: 24px;
  }
}