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

:root {
  --primary: #00a699;
  --primary-dark: #008b7a;
  --accent: #ff6b35;
  --dark: #1a1a1a;
  --light: #f5f5f5;
  --text: #333;
  --border: #e0e0e0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  color: var(--text);
  line-height: 1.6;
  background-color: #fff;
}

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

/* Header */
.header {
  background: #fff;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 20px;
  color: var(--primary);
}

.nav {
  display: flex;
  gap: 30px;
  align-items: center;
}

.nav a {
  text-decoration: none;
  color: var(--text);
  font-weight: 500;
  transition: color 0.3s;
}

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

/* Buttons */
.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s;
  border: none;
  cursor: pointer;
  font-size: 16px;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 16px rgba(0, 166, 153, 0.3);
}

.btn-secondary {
  background: #f0f0f0;
  color: var(--primary);
  border: 2px solid var(--primary);
}

.btn-secondary:hover {
  background: var(--primary);
  color: #fff;
}

.btn-large {
  padding: 16px 40px;
  font-size: 18px;
}

.btn-block {
  width: 100%;
  text-align: center;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, #f5f5f5 0%, #fff 100%);
  padding: 80px 20px;
  text-align: center;
}

.hero-content {
  max-width: 700px;
  margin: 0 auto;
}

.hero h1 {
  font-size: 48px;
  font-weight: 700;
  margin-bottom: 20px;
  color: var(--dark);
  line-height: 1.2;
}

.hero-subtitle {
  font-size: 20px;
  color: var(--primary);
  margin-bottom: 15px;
  font-weight: 600;
}

.hero-description {
  font-size: 16px;
  color: #666;
  margin-bottom: 30px;
  line-height: 1.8;
}

.hero .btn {
  margin-bottom: 20px;
}

.hero-promo {
  font-size: 14px;
  color: var(--accent);
  font-weight: 600;
}

/* Benefits */
.benefits {
  padding: 80px 20px;
  background: #fff;
}

.benefits h2,
.devices h2,
.instruction h2,
.promo h2,
.pricing h2 {
  font-size: 40px;
  text-align: center;
  margin-bottom: 50px;
  color: var(--dark);
}

.section-subtitle {
  text-align: center;
  font-size: 18px;
  color: #666;
  margin-bottom: 40px;
}

.benefits-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
}

.benefit-card {
  padding: 30px;
  border-radius: 12px;
  background: #f9f9f9;
  border: 1px solid var(--border);
  transition: all 0.3s;
  text-align: center;
}

.benefit-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 12px 24px rgba(0, 0, 0, 0.1);
  border-color: var(--primary);
}

.benefit-icon {
  font-size: 48px;
  margin-bottom: 15px;
}

.benefit-card h3 {
  font-size: 20px;
  margin-bottom: 12px;
  color: var(--dark);
}

.benefit-card p {
  color: #666;
  font-size: 15px;
}

/* Devices */
.devices {
  padding: 80px 20px;
  background: #f9f9f9;
}

.devices-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 25px;
  margin-top: 40px;
}

.device-card {
  background: #fff;
  padding: 40px 20px;
  border-radius: 12px;
  text-align: center;
  border: 2px solid transparent;
  transition: all 0.3s;
}

.device-card:hover {
  border-color: var(--primary);
  box-shadow: 0 8px 20px rgba(0, 166, 153, 0.1);
}

.device-icon {
  font-size: 64px;
  margin-bottom: 15px;
  display: block;
}

.device-card h3 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--dark);
}

.device-card p {
  color: #999;
  margin-bottom: 20px;
  font-size: 14px;
}

/* Instruction */
.instruction {
  padding: 80px 20px;
  background: #fff;
}

.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 30px;
  margin-top: 50px;
}

.step {
  position: relative;
  padding-left: 60px;
}

.step-number {
  position: absolute;
  left: 0;
  top: 0;
  width: 50px;
  height: 50px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  font-weight: 700;
}

.step h3 {
  font-size: 20px;
  margin-bottom: 12px;
  color: var(--dark);
}

.step p {
  color: #666;
  font-size: 15px;
  line-height: 1.8;
}

/* Promo */
.promo {
  padding: 80px 20px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: #fff;
  text-align: center;
}

.promo-content {
  max-width: 600px;
  margin: 0 auto;
}

.promo h2 {
  color: #fff;
  margin-bottom: 20px;
}

.promo-highlight {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 20px;
  color: #fff;
}

.promo p {
  font-size: 16px;
  opacity: 0.95;
  margin-bottom: 30px;
  line-height: 1.8;
}

/* Pricing */
.pricing {
  padding: 80px 20px;
  background: #f9f9f9;
}

.pricing h2 {
  margin-bottom: 15px;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
  margin-top: 50px;
}

.pricing-card {
  background: #fff;
  padding: 40px 30px;
  border-radius: 12px;
  border: 2px solid var(--border);
  position: relative;
  transition: all 0.3s;
  display: flex;
  flex-direction: column;
}

.pricing-card:hover {
  border-color: var(--primary);
  box-shadow: 0 12px 30px rgba(0, 166, 153, 0.15);
}

.pricing-featured {
  border-color: var(--primary);
  transform: scale(1.05);
  box-shadow: 0 12px 30px rgba(0, 166, 153, 0.2);
}

.badge {
  position: absolute;
  top: -15px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--accent);
  color: #fff;
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 700;
}

.pricing-card h3 {
  font-size: 24px;
  margin-bottom: 20px;
  color: var(--dark);
}

.price {
  font-size: 48px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 5px;
}

.period {
  font-size: 14px;
  color: #999;
  margin-bottom: 15px;
}

.discount {
  color: var(--accent);
  font-weight: 600;
  font-size: 14px;
  margin-bottom: 15px;
}

.pricing-card .description {
  font-size: 14px;
  color: #666;
  margin-bottom: 20px;
}

.features {
  list-style: none;
  margin-bottom: 30px;
  flex-grow: 1;
}

.features li {
  padding: 10px 0;
  color: #666;
  font-size: 14px;
  border-bottom: 1px solid var(--border);
}

.features li:last-child {
  border-bottom: none;
}

/* Footer */
.footer {
  background: var(--dark);
  color: #fff;
  padding: 40px 20px;
  text-align: center;
  font-size: 14px;
}

/* SEO Block */
.seo-block {
  padding: 80px 20px;
  background: #fff;
}

.seo-content {
  max-width: 800px;
  margin: 0 auto;
}

.seo-content h2 {
  font-size: 40px;
  color: var(--dark);
  margin-bottom: 30px;
  line-height: 1.2;
}

.seo-content h3 {
  font-size: 28px;
  color: var(--dark);
  margin-top: 40px;
  margin-bottom: 20px;
  font-weight: 700;
}

.seo-content p {
  font-size: 16px;
  color: #555;
  line-height: 1.8;
  margin-bottom: 20px;
}

.seo-content ul,
.seo-content ol {
  margin-left: 30px;
  margin-bottom: 20px;
  color: #555;
  font-size: 16px;
  line-height: 1.8;
}

.seo-content li {
  margin-bottom: 12px;
}

.seo-content ol li {
  list-style-type: decimal;
}

.seo-content ul li {
  list-style-type: disc;
}

/* Responsive */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 32px;
  }

  .hero-subtitle {
    font-size: 18px;
  }

  .nav {
    gap: 15px;
    font-size: 14px;
  }

  .nav a {
    display: none;
  }

  .nav a:first-child {
    display: inline;
  }

  .benefits h2,
  .devices h2,
  .instruction h2,
  .pricing h2 {
    font-size: 32px;
  }

  .pricing-featured {
    transform: scale(1);
  }

  .pricing-grid {
    grid-template-columns: 1fr;
  }

  .devices-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .promo-highlight {
    font-size: 24px;
  }

  .seo-content h2 {
    font-size: 32px;
  }

  .seo-content h3 {
    font-size: 24px;
  }

  .seo-content p {
    font-size: 15px;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 15px;
  }

  .hero {
    padding: 60px 15px;
  }

  .hero h1 {
    font-size: 24px;
  }

  .benefits-grid,
  .devices-grid {
    grid-template-columns: 1fr;
  }

  .nav a {
    display: none;
  }

  .step {
    padding-left: 0;
    text-align: center;
  }

  .step-number {
    position: static;
    margin-bottom: 15px;
  }

  .seo-content h2 {
    font-size: 24px;
  }

  .seo-content h3 {
    font-size: 20px;
  }

  .seo-content p,
  .seo-content ul,
  .seo-content ol {
    font-size: 14px;
  }

  .seo-content ul,
  .seo-content ol {
    margin-left: 20px;
  }
}