/* ============================================
   AnsAI — Global Design System
   Premium Dark Theme for AI SaaS
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=JetBrains+Mono:wght@400;500&display=swap');

/* --- CSS Variables --- */
:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: rgba(255,255,255,0.04);
  --bg-card-hover: rgba(255,255,255,0.08);
  --glass: rgba(255,255,255,0.06);
  --glass-border: rgba(255,255,255,0.1);
  --text-primary: #f0f0f5;
  --text-secondary: #8888a0;
  --text-muted: #55556a;
  --accent: #6c5ce7;
  --accent-light: #a29bfe;
  --accent-glow: rgba(108,92,231,0.4);
  --gradient-1: linear-gradient(135deg, #6c5ce7, #00cec9);
  --gradient-2: linear-gradient(135deg, #fd79a8, #6c5ce7);
  --gradient-3: linear-gradient(135deg, #00cec9, #0984e3);
  --success: #00b894;
  --warning: #fdcb6e;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --shadow-glow: 0 0 40px rgba(108,92,231,0.15);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --font-main: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font-main);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }
ul { list-style: none; }

/* --- Utility --- */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section { padding: 120px 0; position: relative; }
.gradient-text {
  background: var(--gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.badge {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 16px; border-radius: 100px;
  background: var(--glass); border: 1px solid var(--glass-border);
  font-size: 0.8rem; font-weight: 500; color: var(--accent-light);
  letter-spacing: 0.5px;
}
.badge .dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--success);
  animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* --- Buttons --- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 14px 32px; border-radius: var(--radius-md);
  font-size: 0.95rem; font-weight: 600;
  transition: var(--transition); position: relative; overflow: hidden;
}
.btn-primary {
  background: var(--gradient-1); color: #fff;
  box-shadow: 0 4px 20px var(--accent-glow);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px var(--accent-glow);
}
.btn-secondary {
  background: var(--glass); color: var(--text-primary);
  border: 1px solid var(--glass-border);
}
.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent);
}
.btn-large { padding: 18px 40px; font-size: 1.05rem; border-radius: var(--radius-lg); }

/* ============ NAVBAR ============ */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  padding: 16px 0;
  background: rgba(10,10,15,0.7);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid transparent;
  transition: var(--transition);
}
.navbar.scrolled {
  padding: 12px 0;
  border-bottom-color: var(--glass-border);
}
.navbar .container {
  display: flex; align-items: center; justify-content: space-between;
}
.nav-logo {
  display: flex; align-items: center; gap: 10px;
  font-size: 1.5rem; font-weight: 800; letter-spacing: -0.5px;
}
.nav-logo .logo-icon {
  width: 36px; height: 36px; border-radius: var(--radius-sm);
  background: var(--gradient-1);
  display: flex; align-items: center; justify-content: center;
  font-size: 1rem; font-weight: 900; color: #fff;
}
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-links a {
  font-size: 0.9rem; font-weight: 500; color: var(--text-secondary);
  transition: var(--transition); position: relative;
}
.nav-links a:hover { color: var(--text-primary); }
.nav-links a::after {
  content: ''; position: absolute; bottom: -4px; left: 0;
  width: 0; height: 2px; background: var(--gradient-1);
  transition: var(--transition);
}
.nav-links a:hover::after { width: 100%; }
.nav-actions { display: flex; align-items: center; gap: 12px; }
.nav-actions .btn { padding: 10px 24px; font-size: 0.85rem; }
.mobile-toggle { display: none; flex-direction: column; gap: 5px; cursor: pointer; }
.mobile-toggle span {
  width: 24px; height: 2px; background: var(--text-primary);
  transition: var(--transition);
}

/* ============ HERO ============ */
.hero {
  min-height: 100vh; display: flex; align-items: center;
  padding-top: 80px; position: relative; overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0; z-index: 0;
}
.hero-bg .orb {
  position: absolute; border-radius: 50%; filter: blur(80px); opacity: 0.3;
}
.hero-bg .orb-1 {
  width: 600px; height: 600px; top: -200px; right: -100px;
  background: var(--accent);
}
.hero-bg .orb-2 {
  width: 400px; height: 400px; bottom: -100px; left: -50px;
  background: #00cec9;
}
.hero-bg .orb-3 {
  width: 300px; height: 300px; top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  background: #fd79a8; opacity: 0.15;
}
.hero-grid {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
}
.hero .container { position: relative; z-index: 1; text-align: center; }
.hero h1 {
  font-size: clamp(2.8rem, 6vw, 5rem);
  font-weight: 900; line-height: 1.1;
  letter-spacing: -2px; margin: 24px 0;
}
.hero .subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--text-secondary); max-width: 600px;
  margin: 0 auto 40px; line-height: 1.7;
}
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero-stats {
  display: flex; gap: 48px; justify-content: center;
  margin-top: 64px; padding-top: 40px;
  border-top: 1px solid var(--glass-border);
}
.hero-stats .stat { text-align: center; }
.hero-stats .stat-number {
  font-size: 2rem; font-weight: 800;
  background: var(--gradient-1);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.hero-stats .stat-label {
  font-size: 0.85rem; color: var(--text-muted); margin-top: 4px;
}

/* ============ FEATURES ============ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 24px; margin-top: 64px;
}
.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 36px;
  transition: var(--transition);
  position: relative; overflow: hidden;
}
.feature-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0;
  height: 2px; background: var(--gradient-1);
  opacity: 0; transition: var(--transition);
}
.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: rgba(108,92,231,0.3);
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
}
.feature-card:hover::before { opacity: 1; }
.feature-icon {
  width: 56px; height: 56px; border-radius: var(--radius-md);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem; margin-bottom: 20px;
}
.feature-icon.chat { background: rgba(108,92,231,0.15); }
.feature-icon.write { background: rgba(253,121,168,0.15); }
.feature-icon.image { background: rgba(0,206,201,0.15); }
.feature-icon.doc { background: rgba(9,132,227,0.15); }
.feature-icon.code { background: rgba(0,184,148,0.15); }
.feature-icon.translate { background: rgba(253,203,110,0.15); }
.feature-card h3 {
  font-size: 1.2rem; font-weight: 700; margin-bottom: 10px;
}
.feature-card p {
  color: var(--text-secondary); font-size: 0.92rem; line-height: 1.6;
}
.feature-card .feature-tag {
  display: inline-block; margin-top: 16px;
  padding: 4px 12px; border-radius: 100px;
  font-size: 0.75rem; font-weight: 600;
  background: rgba(108,92,231,0.1); color: var(--accent-light);
}

/* ============ DEMO SECTION ============ */
.demo-section { background: var(--bg-secondary); }
.demo-window {
  margin-top: 48px;
  background: var(--bg-primary);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-glow);
}
.demo-titlebar {
  display: flex; align-items: center; gap: 8px;
  padding: 14px 20px;
  background: rgba(255,255,255,0.03);
  border-bottom: 1px solid var(--glass-border);
}
.demo-dot {
  width: 12px; height: 12px; border-radius: 50%;
}
.demo-dot.red { background: #ff5f57; }
.demo-dot.yellow { background: #ffbd2e; }
.demo-dot.green { background: #28c840; }
.demo-titlebar span {
  margin-left: auto; font-size: 0.8rem;
  color: var(--text-muted); font-family: var(--font-mono);
}
.demo-content {
  padding: 32px; min-height: 300px;
  display: flex; flex-direction: column; gap: 16px;
}
.demo-chat { display: flex; flex-direction: column; gap: 16px; }
.demo-msg {
  max-width: 80%; padding: 16px 20px;
  border-radius: var(--radius-md); font-size: 0.92rem; line-height: 1.6;
  animation: fadeInUp 0.5s ease-out both;
}
.demo-msg.user {
  align-self: flex-end;
  background: var(--accent); color: #fff;
  border-bottom-right-radius: 4px;
}
.demo-msg.ai {
  align-self: flex-start;
  background: var(--bg-card); border: 1px solid var(--glass-border);
  border-bottom-left-radius: 4px;
}
.demo-input-bar {
  display: flex; gap: 12px; padding: 20px;
  border-top: 1px solid var(--glass-border);
}
.demo-input-bar input {
  flex: 1; padding: 14px 20px;
  background: var(--bg-card); border: 1px solid var(--glass-border);
  border-radius: var(--radius-md); color: var(--text-primary);
  font-size: 0.9rem; font-family: var(--font-main);
  outline: none; transition: var(--transition);
}
.demo-input-bar input:focus { border-color: var(--accent); }
.demo-input-bar button {
  padding: 14px 24px; background: var(--gradient-1);
  border-radius: var(--radius-md); color: #fff;
  font-weight: 600; font-size: 0.9rem;
}

/* ============ PRICING ============ */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px; margin-top: 64px; align-items: start;
}
.price-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 40px 32px; text-align: center;
  transition: var(--transition); position: relative;
}
.price-card.featured {
  border-color: var(--accent);
  box-shadow: var(--shadow-glow);
  transform: scale(1.02);
}
.price-card.featured .popular-badge {
  position: absolute; top: -14px; left: 50%; transform: translateX(-50%);
  padding: 6px 20px; border-radius: 100px;
  background: var(--gradient-1); color: #fff;
  font-size: 0.78rem; font-weight: 700;
  letter-spacing: 0.5px;
}
.price-card:hover { transform: translateY(-4px); }
.price-card.featured:hover { transform: scale(1.02) translateY(-4px); }
.price-card h3 {
  font-size: 1.1rem; font-weight: 600;
  color: var(--text-secondary); margin-bottom: 12px;
}
.price-amount {
  font-size: 3rem; font-weight: 900; margin-bottom: 4px;
}
.price-amount span { font-size: 1rem; font-weight: 400; color: var(--text-muted); }
.price-desc {
  font-size: 0.85rem; color: var(--text-muted); margin-bottom: 32px;
}
.price-features { text-align: left; margin-bottom: 32px; }
.price-features li {
  display: flex; align-items: center; gap: 10px;
  padding: 8px 0; font-size: 0.9rem; color: var(--text-secondary);
}
.price-features li .check {
  color: var(--success); font-weight: 700; font-size: 1rem;
}
.price-card .btn { width: 100%; }

/* ============ SECTION HEADER ============ */
.section-header { text-align: center; max-width: 640px; margin: 0 auto; }
.section-header h2 {
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 800; letter-spacing: -1px; margin: 16px 0;
}
.section-header p {
  color: var(--text-secondary); font-size: 1.05rem; line-height: 1.7;
}

/* ============ FAQ ============ */
.faq-list { max-width: 720px; margin: 48px auto 0; }
.faq-item {
  border-bottom: 1px solid var(--glass-border);
  padding: 24px 0;
}
.faq-question {
  display: flex; align-items: center; justify-content: space-between;
  font-size: 1rem; font-weight: 600; cursor: pointer;
  color: var(--text-primary); transition: var(--transition);
  width: 100%; text-align: left; padding: 0;
}
.faq-question:hover { color: var(--accent-light); }
.faq-question .icon {
  font-size: 1.3rem; transition: transform 0.3s ease;
  color: var(--text-muted);
}
.faq-item.active .faq-question .icon { transform: rotate(45deg); color: var(--accent); }
.faq-answer {
  max-height: 0; overflow: hidden;
  transition: max-height 0.4s ease, padding 0.3s ease;
}
.faq-item.active .faq-answer {
  max-height: 200px; padding-top: 16px;
}
.faq-answer p {
  font-size: 0.92rem; color: var(--text-secondary); line-height: 1.7;
}

/* ============ CTA ============ */
.cta-section {
  text-align: center;
  background: var(--bg-secondary);
  position: relative; overflow: hidden;
}
.cta-section::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(circle at center, var(--accent-glow), transparent 70%);
  opacity: 0.3;
}
.cta-section .container { position: relative; z-index: 1; }
.cta-section h2 {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 900; letter-spacing: -1px; margin-bottom: 16px;
}
.cta-section p {
  color: var(--text-secondary); font-size: 1.1rem;
  max-width: 500px; margin: 0 auto 36px;
}

/* ============ FOOTER ============ */
.footer {
  padding: 64px 0 32px;
  border-top: 1px solid var(--glass-border);
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
}
.footer-brand .nav-logo { margin-bottom: 16px; }
.footer-brand p {
  color: var(--text-muted); font-size: 0.88rem; line-height: 1.6;
  max-width: 280px;
}
.footer-col h4 {
  font-size: 0.85rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 1px;
  color: var(--text-muted); margin-bottom: 20px;
}
.footer-col a {
  display: block; padding: 6px 0;
  font-size: 0.9rem; color: var(--text-secondary);
  transition: var(--transition);
}
.footer-col a:hover { color: var(--text-primary); }
.footer-bottom {
  margin-top: 48px; padding-top: 24px;
  border-top: 1px solid var(--glass-border);
  display: flex; justify-content: space-between; align-items: center;
  font-size: 0.82rem; color: var(--text-muted);
}

/* ============ ANIMATIONS ============ */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}
.animate-in {
  opacity: 0; transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.animate-in.visible {
  opacity: 1; transform: translateY(0);
}

/* ============ RESPONSIVE ============ */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .mobile-toggle { display: flex; }
  .nav-links.active {
    display: flex; flex-direction: column;
    position: absolute; top: 100%; left: 0; right: 0;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--glass-border);
    padding: 24px;
  }
  .hero-stats { flex-direction: column; gap: 24px; }
  .features-grid { grid-template-columns: 1fr; }
  .pricing-grid { grid-template-columns: 1fr; }
  .price-card.featured { transform: none; }
  .price-card.featured:hover { transform: translateY(-4px); }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .footer-bottom { flex-direction: column; gap: 12px; text-align: center; }
  .hero h1 { letter-spacing: -1px; }
  .section { padding: 80px 0; }
}

/* --- AUTH MODAL --- */
.modal-overlay { position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.6); backdrop-filter: blur(5px); z-index: 9999; display: flex; align-items: center; justify-content: center; opacity: 0; visibility: hidden; transition: var(--transition); }
.modal-overlay.active { opacity: 1; visibility: visible; }
.modal-content { background: var(--bg-card); border: 1px solid var(--glass-border); border-radius: var(--radius-lg); width: 100%; max-width: 400px; padding: 32px; position: relative; transform: translateY(20px); transition: var(--transition); box-shadow: 0 20px 40px rgba(0,0,0,0.4); }
.modal-overlay.active .modal-content { transform: translateY(0); }
.modal-close { position: absolute; top: 16px; right: 16px; background: transparent; border: none; color: var(--text-muted); font-size: 1.5rem; cursor: pointer; transition: var(--transition); }
.modal-close:hover { color: var(--text-primary); }
.modal-header h3 { font-size: 1.5rem; margin-bottom: 8px; }
.modal-header p { color: var(--text-secondary); font-size: 0.9rem; margin-bottom: 24px; }
.auth-form .form-group { margin-bottom: 16px; text-align: left; }
.auth-form label { display: block; font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 8px; font-weight: 500; }
.auth-form input { width: 100%; padding: 12px 16px; background: var(--bg-secondary); border: 1px solid var(--glass-border); border-radius: var(--radius-sm); color: var(--text-primary); font-family: var(--font-main); outline: none; transition: var(--transition); }
.auth-form input:focus { border-color: var(--accent); }
.btn-full { width: 100%; padding: 14px; font-size: 1rem; margin-top: 8px; }
.modal-footer { margin-top: 24px; text-align: center; font-size: 0.9rem; color: var(--text-secondary); }
.modal-footer a { color: var(--text-secondary); text-decoration: none; }
.modal-footer span { color: var(--accent-light); font-weight: 600; }
.auth-error { color: #ff6b6b; font-size: 0.85rem; margin-bottom: 12px; text-align: center; }