:root {
  color-scheme: light;
  --bg: #ffffff;
  --surface: #ffffff;
  --surface-strong: #11110f;
  --text: #161512;
  --muted: #5c5951;
  --line: #d9d4c8;
  --line-strong: #b7af9b;
  --focus: #11110f;

  --container: 900px;
  --pad-mobile: 20px;
  --pad-tablet: 30px;

  --space-1: 0.5rem;
  --space-2: 0.75rem;
  --space-3: 1rem;
  --space-4: 1.5rem;
  --space-5: 2.25rem;
  --space-6: clamp(2.75rem, 6vw, 5rem);

  --radius: 0.35rem;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic UI", "YuGothic", "Meiryo", sans-serif;
  font-size: 16px;
  line-height: 1.76;
  letter-spacing: 0.01em;
  text-rendering: optimizeLegibility;
}

a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

a:hover {
  border-bottom-color: currentColor;
}

a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 3px;
  border-radius: var(--radius);
}

.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-3);
  z-index: 50;
  padding: var(--space-2) var(--space-3);
  background: var(--surface-strong);
  color: #f7f4ea;
  border-radius: var(--radius);
}

.skip-link:focus {
  top: var(--space-2);
}

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--pad-mobile);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(6px);
}

.header-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  padding-block: 0.9rem;
}

.site-mark {
  margin: 0;
  font-size: 0.8rem;
  font-weight: 620;
  letter-spacing: 0.09em;
  color: var(--muted);
  text-transform: uppercase;
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-3);
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-list a {
  display: inline-block;
  font-size: 0.95rem;
  font-weight: 520;
  padding: 0.1rem 0;
}

.nav-list a[aria-current="page"] {
  border-bottom-color: currentColor;
}

.section {
  padding-block: var(--space-6);
  border-top: 1px solid var(--line);
}

.hero {
  border-top: 0;
  padding-top: clamp(3.25rem, 8vw, 6rem);
}

.hero-inner {
  display: grid;
  gap: var(--space-3);
}

.eyebrow {
  margin: 0;
  font-size: 0.76rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

h1,
h2,
h3 {
  margin: 0;
  line-height: 1.3;
  letter-spacing: 0.01em;
  font-weight: 620;
}

h1 {
  font-size: 38px;
  margin-top: 0.2em;
}

h2 {
  font-size: 24px;
  margin-bottom: 1.1rem;
}

h3 {
  font-size: 20px;
  margin-bottom: 0.75rem;
}

p,
li,
dt,
dd {
  font-size: 16px;
}

p {
  margin: 0;
}

.lead {
  color: var(--text);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1.76;
}

.hero-cta {
  margin-top: var(--space-2);
  font-weight: 520;
}

.card {
  padding-block: var(--space-4);
  border-top: 1px solid var(--line);
}

.card:first-of-type {
  border-top-color: var(--line-strong);
}

.company-data {
  margin: 0;
  display: grid;
  grid-template-columns: 1fr;
}

.company-data div {
  padding-block: var(--space-3);
}

.company-data dt {
  margin: 0;
  font-size: 0.86rem;
  font-weight: 620;
  letter-spacing: 0.05em;
  color: var(--muted);
}

.company-data dd {
  margin: var(--space-1) 0 0;
}

.patent-list {
  margin: var(--space-3) 0 0;
  padding-left: 1.2rem;
}

.patent-list li + li {
  margin-top: var(--space-2);
}

.contact-strip h2 {
  margin-bottom: var(--space-2);
}

.site-footer {
  padding-block: var(--space-5);
  background: var(--surface);
  border-top: 1px solid var(--line);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}

.footer-inner p {
  margin: 0;
  font-size: 0.93rem;
  color: var(--muted);
}

.footer-links {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-3);
}

.footer-links a {
  font-size: 0.93rem;
}

@media (min-width: 600px) {
  .container {
    padding-inline: var(--pad-tablet);
  }

  h1 {
    font-size: 75px;
  }

  h2 {
    font-size: 24px;
  }

  h3 {
    font-size: 24px;
  }

  p,
  li,
  dt,
  dd {
    font-size: 18px;
  }

  .lead {
    font-size: 24px;
    line-height: 1.76;
  }
}

@media (min-width: 900px) {
  .container {
    padding-inline: 0;
  }

  h1 {
    font-size: 90px;
  }

  h2 {
    font-size: 28px;
  }

  h3 {
    font-size: 28px;
  }

  .lead {
    font-size: 28px;
    line-height: 1.8;
  }

  .company-data {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(2rem, 6vw, 6rem);
  }

  .company-data div {
    border-bottom: 0;
  }
}

@media (max-width: 47.99rem) {
  .header-inner {
    align-items: flex-start;
  }

  .nav-list {
    gap: var(--space-2);
  }

  .section {
    padding-block: var(--space-5);
  }
}