:root {
  --accent: #3A7BD5;
  --bg: #FAFAFA;
  --text: #1A1A1A;
  --muted: #6B6B6B;
  --border: #E8E8E8;
  --white: #FFFFFF;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Inter', 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  font-size: 18px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: opacity 0.2s ease;
}

a:hover {
  opacity: 0.7;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 32px;
}

.section {
  padding: 120px 0;
}

/* Header */
.site-header {
  background: var(--white);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
  background: rgba(255, 255, 255, 0.9);
}

.logo {
  font-weight: 600;
  font-size: 15px;
  letter-spacing: -0.01em;
  padding: 20px 0;
  color: var(--text);
}

/* Hero */
.hero {
  padding: 140px 0 120px;
  text-align: center;
}

.hero h1 {
  font-size: clamp(48px, 8vw, 72px);
  line-height: 1.05;
  margin: 0 0 16px 0;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--text);
}

.subhead {
  font-size: clamp(20px, 3vw, 28px);
  margin: 0 0 24px 0;
  font-weight: 400;
  color: var(--muted);
}

.tagline {
  font-size: 18px;
  color: var(--text);
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.6;
}

.note {
  color: var(--muted);
  margin: 0 0 48px 0;
  font-size: 16px;
}

.hero img {
  margin: 0 auto;
  max-width: 600px;
  border-radius: 16px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.08);
}

/* Products */
.products {
  background: var(--white);
}

.products .product {
  display: grid;
  grid-template-columns: 1fr;
  gap: 48px;
  padding: 80px 0;
  align-items: center;
}

.products .product:first-child {
  padding-top: 0;
}

.products .product:last-child {
  padding-bottom: 0;
}

.products .product + .product {
  border-top: 1px solid var(--border);
}

.product-text h2 {
  font-size: clamp(28px, 4vw, 42px);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
  margin: 0 0 16px 0;
  line-height: 1.2;
}

.product-text p {
  margin: 0 0 24px 0;
  font-size: 20px;
  color: var(--muted);
  line-height: 1.6;
}

.product-text ul {
  list-style: none;
  padding: 0;
}

.product-text li {
  padding: 8px 0 8px 24px;
  position: relative;
  font-size: 17px;
  color: var(--text);
}

.product-text li:before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-weight: bold;
  font-size: 20px;
}

.product-media {
  display: flex;
  justify-content: center;
  align-items: center;
}

.product-media img {
  border-radius: 20px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.1);
  max-width: 400px;
  width: 100%;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.product-media img:hover {
  transform: translateY(-4px);
  box-shadow: 0 24px 72px rgba(0,0,0,0.12);
}

/* How/Single line */
.how {
  text-align: center;
  padding: 100px 0;
}

.single-line {
  font-weight: 500;
  font-size: clamp(24px, 4vw, 36px);
  color: var(--text);
  letter-spacing: -0.01em;
  line-height: 1.4;
  max-width: 800px;
  margin: 0 auto;
}

/* CTA */
.cta {
  background: var(--white);
  text-align: center;
  padding: 100px 0;
}

.cta-heading {
  font-size: clamp(28px, 4vw, 42px);
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text);
  line-height: 1.3;
}

.cta-heading a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 4px;
  text-decoration-thickness: 2px;
}

.cta-heading a:hover {
  opacity: 0.8;
}

/* Footer */
.site-footer {
  background: var(--white);
  border-top: 1px solid var(--border);
  padding: 48px 0;
}

.site-footer .container {
  display: flex;
  flex-direction: column;
  gap: 12px;
  text-align: center;
  font-size: 15px;
  color: var(--muted);
}

.site-footer a {
  color: var(--text);
  font-weight: 500;
}

/* Responsive */
@media (min-width: 900px) {
  .section { 
    padding: 140px 0; 
  }
  
  .products .product {
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    padding: 100px 0;
  }
  
  .products .product:nth-child(even) .product-media {
    order: -1;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0 24px;
  }
  
  .section {
    padding: 80px 0;
  }
  
  .hero {
    padding: 100px 0 80px;
  }
  
  .products .product {
    padding: 60px 0;
  }
}

/* Accessibility */
:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 4px;
  border-radius: 4px;
}