:root {
  --dark-900: #0D1117;
  --dark-800: #141C26;
  --dark-700: #1A2332;
  --dark-600: #2A3A4E;
  --cyan-400: #33CFFF;
  --cyan-500: #00BFFF;
  --cyan-600: #00A3E0;
  --cyan-700: #0090C8;
  --cyan-glow: rgba(0,191,255,0.4);
  --light-50: #FFFFFF;
  --light-100: #F0F4F8;
  --light-200: #E6F7FF;
  --text-900: #1A2332;
  --text-600: #7A8A9E;
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "Inter", sans-serif;
  font-weight: 400;
  color: var(--text-900);
  background: var(--light-50);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* TYPOGRAPHY */
.section-title {
  font-size: 28px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 12px;
  color: var(--text-900);
}
.section-subtitle {
  font-size: 16px;
  text-align: center;
  color: var(--text-600);
  margin-bottom: 48px;
}

/* BUTTONS */
.cta-button {
  display: inline-block;
  background: var(--cyan-500);
  color: #fff;
  font-family: "Inter", sans-serif;
  font-weight: 600;
  font-size: 16px;
  padding: 14px 32px;
  border-radius: 12px;
  border: none;
  cursor: pointer;
  transition: background 0.3s, box-shadow 0.3s;
}
.cta-button:hover {
  background: var(--cyan-600);
  box-shadow: 0 0 24px var(--cyan-glow);
}
.cta-button:active {
  background: var(--cyan-700);
}

/* ANIMATIONS */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

@keyframes glowPulse {
  0%, 100% { box-shadow: 0 0 20px rgba(0,191,255,0.3); }
  50% { box-shadow: 0 0 28px rgba(0,191,255,0.5); }
}

/* HEADER */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: var(--light-50);
  transition: box-shadow 0.3s;
}
.header.scrolled {
  box-shadow: 0 2px 16px rgba(0,0,0,0.08);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  font-size: 24px;
  font-weight: 700;
  line-height: 1;
}
.logo .logo-ai { color: var(--cyan-500); }
.logo-light { color: #fff; }
.logo-light .logo-ai { color: var(--cyan-500); }

.nav-desktop {
  display: none;
  align-items: center;
  gap: 32px;
}
.nav-desktop a {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-600);
  transition: color 0.3s;
}
.nav-desktop a:hover { color: var(--cyan-500); }
.header-cta-wrap { display: none; }

/* Burger */
.burger {
  display: flex;
  flex-direction: column;
  justify-content: center;
  width: 40px; height: 40px;
  cursor: pointer;
  background: none;
  border: none;
  gap: 5px;
}
.burger span {
  display: block;
  width: 24px; height: 2px;
  background: var(--text-900);
  border-radius: 2px;
  transition: transform 0.3s, opacity 0.3s;
}
.burger.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.burger.active span:nth-child(2) { opacity: 0; }
.burger.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Mobile menu */
.mobile-menu {
  display: none;
  position: fixed;
  top: 72px; left: 0; right: 0; bottom: 0;
  background: var(--light-50);
  z-index: 999;
  padding: 32px 20px;
  flex-direction: column;
  gap: 24px;
}
.mobile-menu.open { display: flex; }
.mobile-menu a {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-900);
}
.mobile-menu .cta-button {
  text-align: center;
  margin-top: 16px;
}

/* HERO */
.hero {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--dark-700) 0%, var(--dark-600) 50%, var(--dark-700) 100%);
  padding: 140px 0 80px;
  min-height: 100vh;
  display: flex;
  align-items: center;
}
.hero-glow1, .hero-glow2, .hero-glow3 {
  position: absolute;
  pointer-events: none;
  border-radius: 50%;
}
.hero-glow1 {
  top: -20%; left: -10%;
  width: 500px; height: 500px;
  background: radial-gradient(circle, rgba(0,191,255,0.08) 0%, transparent 70%);
}
.hero-glow2 {
  bottom: -10%; right: -5%;
  width: 400px; height: 400px;
  background: radial-gradient(circle, rgba(0,191,255,0.06) 0%, transparent 70%);
}
.hero-glow3 {
  top: 40%; left: 60%;
  width: 350px; height: 350px;
  background: radial-gradient(circle, rgba(0,191,255,0.05) 0%, transparent 70%);
}
.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 720px;
  margin: 0 auto;
}
.hero-logo {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 24px;
  color: #fff;
}
.hero-logo .logo-ai { color: var(--cyan-500); }

.hero h1 {
  font-size: 36px;
  font-weight: 700;
  color: #fff;
  line-height: 1.2;
  margin-bottom: 20px;
}
.hero .hero-desc {
  font-size: 18px;
  color: rgba(255,255,255,0.85);
  margin-bottom: 40px;
  line-height: 1.6;
}
.hero-buttons {
  display: flex;
  flex-direction: column;
  gap: 16px;
  align-items: center;
}
.hero-cta {
  box-shadow: 0 0 20px var(--cyan-glow);
  animation: glowPulse 3s ease-in-out infinite;
}
.hero-cta:hover {
  background: var(--cyan-600);
  box-shadow: 0 0 32px rgba(0,191,255,0.6);
}
.hero-secondary {
  display: inline-block;
  padding: 14px 32px;
  border: 2px solid rgba(255,255,255,0.5);
  border-radius: 12px;
  color: #fff;
  font-weight: 600;
  font-size: 16px;
  transition: border-color 0.3s, background 0.3s;
}
.hero-secondary:hover {
  border-color: #fff;
  background: rgba(255,255,255,0.1);
}

/* HOW IT WORKS */
.how-it-works {
  background: var(--light-100);
  padding: 80px 0;
}
.steps-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}
.step-card {
  background: var(--light-50);
  border-radius: 16px;
  padding: 40px 28px 32px;
  text-align: center;
  box-shadow: 0 4px 24px rgba(0,0,0,0.08);
  position: relative;
  overflow: hidden;
}
.step-number {
  position: absolute;
  top: 8px; left: 20px;
  font-size: 56px;
  font-weight: 700;
  color: var(--light-100);
  line-height: 1;
  z-index: 0;
}
.step-icon {
  width: 64px; height: 64px;
  border-radius: 50%;
  background: var(--light-200);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  margin: 0 auto 20px;
  position: relative;
  z-index: 1;
}
.step-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
  position: relative;
  z-index: 1;
}
.step-card p {
  font-size: 15px;
  color: var(--text-600);
  line-height: 1.6;
  position: relative;
  z-index: 1;
}

/* EXAMPLES */
.examples {
  background: var(--light-50);
  padding: 80px 0;
}
.examples-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}
.example-card {
  background: var(--light-50);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 4px 24px rgba(0,0,0,0.08);
}
.example-slider {
  position: relative;
  width: 100%;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  cursor: col-resize;
  user-select: none;
}
.example-slider .img-before,
.example-slider .img-after {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 1px;
}
.example-slider .img-before {
  background: #9CA3AF;
  z-index: 2;
}
.example-slider .img-after {
  background: #6BA38E;
  z-index: 1;
}
.example-slider .slider-handle {
  position: absolute;
  top: 0; bottom: 0;
  width: 3px;
  background: #fff;
  z-index: 5;
  left: 50%;
  transform: translateX(-50%);
  pointer-events: none;
}
.example-slider .slider-handle::after {
  content: "\25C0\25B6";
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  width: 36px; height: 36px;
  background: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  color: var(--text-900);
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}
.example-slider input[type="range"] {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  z-index: 10;
  opacity: 0;
  cursor: col-resize;
  margin: 0;
  -webkit-appearance: none;
}
.example-badges {
  position: absolute;
  top: 12px; left: 12px; right: 12px;
  display: flex;
  justify-content: space-between;
  z-index: 8;
  pointer-events: none;
}
.badge-before, .badge-after {
  font-size: 12px;
  font-weight: 600;
  padding: 4px 14px;
  border-radius: 20px;
  color: #fff;
}
.badge-before { background: #6B7280; }
.badge-after { background: var(--cyan-500); }
.example-caption {
  padding: 16px 20px;
  font-size: 15px;
  font-weight: 600;
  text-align: center;
}

/* PRICING */
.pricing {
  background: var(--light-100);
  padding: 80px 0;
}
.pricing-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  align-items: start;
}
.pricing-card {
  background: var(--light-50);
  border-radius: 16px;
  padding: 36px 28px;
  box-shadow: 0 4px 24px rgba(0,0,0,0.08);
  position: relative;
  border: 2px solid transparent;
}
.pricing-card.popular {
  border-color: var(--cyan-500);
  box-shadow: 0 0 16px var(--cyan-glow), 0 4px 24px rgba(0,0,0,0.08);
}
.pricing-badge {
  position: absolute;
  top: -14px; left: 50%;
  transform: translateX(-50%);
  background: var(--cyan-500);
  color: #fff;
  font-size: 13px;
  font-weight: 600;
  padding: 4px 20px;
  border-radius: 20px;
  white-space: nowrap;
}
.pricing-card h3 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 8px;
}
.pricing-price {
  font-size: 42px;
  font-weight: 700;
  line-height: 1.1;
}
.pricing-period {
  font-size: 16px;
  font-weight: 400;
  color: var(--text-600);
  margin-bottom: 24px;
  display: inline-block;
}
.pricing-features { margin-bottom: 28px; }
.pricing-features li {
  padding: 8px 0;
  font-size: 15px;
  color: var(--text-600);
  display: flex;
  align-items: flex-start;
  gap: 10px;
}
.pricing-features li::before {
  content: "\2713";
  color: var(--cyan-500);
  font-weight: 700;
  flex-shrink: 0;
}
.pricing-card .cta-button {
  display: block;
  width: 100%;
  text-align: center;
}
.pricing-note {
  text-align: center;
  margin-top: 40px;
  font-size: 16px;
  color: var(--text-600);
}
.pricing-note a {
  color: var(--cyan-500);
  font-weight: 600;
}
.pricing-note a:hover { color: var(--cyan-600); }

/* FAQ */
.faq {
  background: var(--light-50);
  padding: 80px 0;
}
.faq-list {
  max-width: 800px;
  margin: 0 auto;
}
.faq-item {
  border-bottom: 1px solid #E5E7EB;
}
.faq-question {
  width: 100%;
  background: none;
  border: none;
  font-family: "Inter", sans-serif;
  font-size: 16px;
  font-weight: 600;
  color: var(--text-900);
  padding: 20px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  text-align: left;
  gap: 16px;
}
.faq-icon {
  flex-shrink: 0;
  font-size: 22px;
  color: var(--text-600);
  transition: transform 0.3s;
  font-weight: 300;
}
.faq-item.active .faq-icon {
  transform: rotate(45deg);
}
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}
.faq-answer-inner {
  padding: 0 0 20px;
  font-size: 15px;
  color: var(--text-600);
  line-height: 1.7;
}

/* FINAL CTA */
.final-cta {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--dark-700) 0%, var(--dark-600) 50%, var(--dark-700) 100%);
  padding: 80px 0;
  text-align: center;
}
.final-cta::before {
  content: "";
  position: absolute;
  top: -30%; right: -10%;
  width: 400px; height: 400px;
  background: radial-gradient(circle, rgba(0,191,255,0.08) 0%, transparent 70%);
  pointer-events: none;
}
.final-cta-content { position: relative; z-index: 1; }
.final-cta h2 {
  font-size: 28px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 16px;
  line-height: 1.3;
}
.final-cta .final-desc {
  font-size: 18px;
  color: rgba(255,255,255,0.85);
  margin-bottom: 36px;
}
.final-cta .big-cta {
  font-size: 18px;
  padding: 18px 40px;
}
.final-cta .final-note {
  margin-top: 16px;
  font-size: 14px;
  color: rgba(255,255,255,0.7);
}

/* FOOTER */
.footer {
  background: var(--dark-800);
  padding: 48px 0 24px;
  color: rgba(255,255,255,0.8);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  margin-bottom: 32px;
}
.footer-brand p {
  font-size: 14px;
  color: rgba(255,255,255,0.6);
  line-height: 1.6;
  margin-top: 12px;
}
.footer-nav h4, .footer-contact h4 {
  font-size: 16px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 16px;
}
.footer-nav a {
  display: block;
  font-size: 14px;
  color: rgba(255,255,255,0.6);
  margin-bottom: 10px;
  transition: color 0.3s;
}
.footer-nav a:hover { color: var(--cyan-500); }
.footer-contact a {
  color: var(--cyan-500);
  font-size: 14px;
}
.footer-contact a:hover { color: var(--cyan-400); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 13px;
  color: rgba(255,255,255,0.5);
}
.footer-bottom a { color: rgba(255,255,255,0.5); }
.footer-bottom a:hover { color: var(--cyan-500); }

/* SCROLL TO TOP */
.scroll-top {
  position: fixed;
  bottom: 24px; right: 24px;
  width: 48px; height: 48px;
  background: var(--cyan-500);
  color: #fff;
  border: none;
  border-radius: 50%;
  font-size: 20px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 16px var(--cyan-glow);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s, background 0.3s;
  z-index: 900;
}
.scroll-top.visible { opacity: 1; visibility: visible; }
.scroll-top:hover { background: var(--cyan-600); }

/* RESPONSIVE 768px */
@media (min-width: 768px) {
  .section-title { font-size: 32px; }
  .hero h1 { font-size: 44px; }
  .hero-buttons { flex-direction: row; justify-content: center; }
  .steps-grid { grid-template-columns: repeat(3, 1fr); gap: 24px; }
  .examples-grid { grid-template-columns: repeat(2, 1fr); }
  .pricing-grid { grid-template-columns: repeat(3, 1fr); gap: 20px; }
  .pricing-card.popular { transform: scale(1.05); z-index: 2; }
  .footer-grid { grid-template-columns: 2fr 1fr 1fr; }
  .footer-bottom { flex-direction: row; justify-content: space-between; }
}

/* RESPONSIVE 1024px */
@media (min-width: 1024px) {
  .section-title { font-size: 36px; }
  .hero h1 { font-size: 52px; }
  .hero { padding: 0; min-height: 100vh; }
  .nav-desktop { display: flex; }
  .header-cta-wrap { display: block; }
  .burger { display: none; }
  .final-cta h2 { font-size: 36px; }
}




/* Строчная i увеличенная до высоты заглавной A */
.logo-i {
  font-size: 1.00em;
  line-height: 0;
  vertical-align: baseline;
  position: relative;
  top: 0.01em;
}

/* Кнопки тарифов */
.btn-primary {
  display: inline-block;
  margin-top: 1.5rem;
  padding: 0.75rem 2rem;
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  color: #fff;
  text-decoration: none;
  border-radius: 0.5rem;
  font-weight: 600;
  font-size: 1rem;
  transition: transform 0.2s, box-shadow 0.2s;
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}
.pricing-card.popular .btn-primary {
  background: linear-gradient(135deg, #8b5cf6, #a78bfa);
}