:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f6f6f4;
  --color-text: #16181d;
  --color-muted: #5b6068;
  --color-line: #e3e3df;
  --color-accent: #111317;
  --max-width: 880px;
  --space: clamp(2.5rem, 6vw, 5rem);
  font-family: system-ui, -apple-system, "Hiragino Kaku Gothic ProN",
    "Hiragino Sans", "Noto Sans JP", Meiryo, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a {
  color: inherit;
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: 1.5rem;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--color-line);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
  gap: 1rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.01em;
}

.brand-mark {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  border: 3px solid var(--color-accent);
}

.brand-name {
  font-size: 1.05rem;
}

.site-nav {
  display: flex;
  gap: 1.4rem;
  font-size: 0.9rem;
}

.site-nav a {
  text-decoration: none;
  color: var(--color-muted);
  transition: color 0.15s ease;
}

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

/* Hero */
.hero {
  padding-block: clamp(4rem, 12vw, 8rem);
  border-bottom: 1px solid var(--color-line);
}

.hero-kicker {
  margin: 0;
  font-size: 0.8rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-muted);
}

.hero-title {
  margin: 0.4rem 0 0;
  font-size: clamp(2.6rem, 9vw, 4.5rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
  font-weight: 800;
}

.hero-reading {
  margin: 0.5rem 0 0;
  color: var(--color-muted);
  letter-spacing: 0.08em;
}

.hero-lead {
  margin: 1.8rem 0 0;
  max-width: 40ch;
  font-size: 1.05rem;
  color: var(--color-text);
}

.hero-lead:empty {
  display: none;
}

/* Sections */
.section {
  padding-block: var(--space);
}

.section-alt {
  background: var(--color-bg-alt);
}

.section-title {
  margin: 0 0 1.5rem;
  font-size: 1.4rem;
  letter-spacing: 0.02em;
}

.section-lead {
  margin: 0 0 2rem;
  max-width: 60ch;
  color: var(--color-muted);
}

.section-lead:empty {
  display: none;
}

/* Overview table */
.overview {
  margin: 0;
  border-top: 1px solid var(--color-line);
}

.overview-row {
  display: grid;
  grid-template-columns: 9rem 1fr;
  gap: 1rem;
  padding-block: 0.9rem;
  border-bottom: 1px solid var(--color-line);
}

.overview dt {
  margin: 0;
  font-weight: 600;
  color: var(--color-muted);
  font-size: 0.95rem;
}

.overview dd {
  margin: 0;
}

.overview dd:empty::after {
  content: "—";
  color: var(--color-line);
}

@media (max-width: 540px) {
  .overview-row {
    grid-template-columns: 1fr;
    gap: 0.2rem;
  }
}

/* Services */
.services {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.service-card {
  padding: 1.4rem;
  background: var(--color-bg);
  border: 1px solid var(--color-line);
  border-radius: 12px;
}

.service-card h3 {
  margin: 0 0 0.5rem;
  font-size: 1.05rem;
}

.service-card h3:empty::after {
  content: "サービス";
  color: var(--color-line);
}

.service-card p {
  margin: 0;
  color: var(--color-muted);
  font-size: 0.95rem;
}

/* Contact */
.contact-line {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 1rem;
  align-items: baseline;
  margin: 0;
}

.contact-label {
  font-weight: 600;
  color: var(--color-muted);
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-line);
  padding-block: 2rem;
}

.copyright {
  margin: 0;
  font-size: 0.85rem;
  color: var(--color-muted);
}