/* ===== RESET & BASE ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --white: #ffffff;
  --black: #0a0a0a;
  --gray-bg: #f5f5f5;
  --gray-mid: #999;
  --gray-text: #555;
  --font-en: 'Inter', sans-serif;
  --font-ja: 'Noto Sans JP', 'Hiragino Sans', sans-serif;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  background: var(--white);
  color: var(--black);
  font-family: var(--font-ja);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

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

/* ===== CONTAINER ===== */
.container {
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== HEADER ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid #e8e8e8;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

.header-logo {
  height: 22px;
  width: auto;
}

.header-nav {
  display: none;
  gap: 36px;
}

.header-nav a {
  font-family: var(--font-en);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--black);
  transition: opacity 0.2s;
}

.header-nav a:hover {
  opacity: 0.35;
}

/* ===== HERO ===== */
.hero {
  min-height: 100dvh;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  padding: 80px 24px 60px;
  text-align: center;
}

.hero-logo {
  width: min(520px, 78vw);
  margin: 0 auto 48px;
}

.hero-catch {
  font-family: var(--font-ja);
  font-size: clamp(13px, 2.5vw, 16px);
  font-weight: 400;
  color: var(--gray-mid);
  letter-spacing: 0.2em;
}

/* ===== SECTION BASE ===== */
.section {
  padding: 120px 0;
}

.section-label {
  display: block;
  font-family: var(--font-en);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gray-mid);
  margin-bottom: 20px;
}

.section-title {
  font-family: var(--font-en);
  font-size: clamp(52px, 10vw, 96px);
  font-weight: 900;
  line-height: 0.95;
  letter-spacing: -0.03em;
  margin-bottom: 64px;
}

/* ===== BUSINESS ===== */
.business {
  background: var(--black);
  color: var(--white);
}

.business .section-label {
  color: #555;
}

.business .section-title {
  color: var(--white);
}

.business-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  border: 1px solid #222;
}

.business-card {
  background: #111;
  padding: 48px 40px;
  border: 1px solid #222;
  transition: background 0.25s ease, border-color 0.25s ease;
  cursor: default;
}

.business-card:hover {
  background: #1a1a1a;
  border-color: #444;
}

.card-num {
  display: block;
  font-family: var(--font-en);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: #444;
  margin-bottom: 24px;
}

.business-card h3 {
  font-family: var(--font-en);
  font-size: clamp(18px, 3vw, 22px);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--white);
  margin-bottom: 16px;
}

.business-card p {
  font-size: 14px;
  line-height: 1.9;
  color: #777;
}

/* ===== PHILOSOPHY ===== */
.philosophy {
  background: var(--black);
  color: var(--white);
}

.philosophy .section-label {
  color: #555;
}

.philosophy .section-title {
  color: var(--white);
}

.philosophy-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 64px;
}

.philosophy-body {
  font-size: 15px;
  line-height: 2;
  color: #888;
}

.philosophy-photo img {
  width: 100%;
  max-width: 440px;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  object-position: center top;
  filter: brightness(0.9);
}

/* ===== FOOTER ===== */
.footer {
  background: var(--white);
  padding: 80px 0 48px;
  border-top: 1px solid #e8e8e8;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 16px;
}

.footer-title {
  font-family: var(--font-en);
  font-size: 12px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.05em;
  margin-bottom: 20px;
}

.footer-title a {
  color: var(--black);
  transition: opacity 0.2s;
}

.footer-title a:hover {
  opacity: 0.5;
}

.footer-meta {
  font-family: var(--font-en);
  font-size: 12px;
  color: var(--gray-mid);
  letter-spacing: 0.05em;
}

.footer-meta a:hover {
  opacity: 0.5;
}

.footer-copy {
  font-family: var(--font-en);
  font-size: 11px;
  color: #ccc;
  margin-top: 40px;
}

.footer-policy-link {
  color: #ccc;
  margin-right: 20px;
  transition: opacity 0.2s;
}

.footer-policy-link:hover {
  opacity: 0.5;
}

/* ===== MOBILE: HEADER SCROLL CONTROL ===== */
@media (max-width: 639px) {
  .header {
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
    background: rgba(10, 10, 10, 0.96);
    border-bottom-color: #222;
  }

  .header.is-visible {
    opacity: 1;
    pointer-events: auto;
  }

  .header-logo {
    filter: invert(1);
  }

  .hero {
    padding-top: 0;
    padding-bottom: 0;
  }

  .footer-copy {
    align-self: flex-end;
  }
}


/* ===== RESPONSIVE: TABLET ===== */
@media (min-width: 640px) {
  .header-nav {
    display: flex;
  }

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

}

/* ===== RESPONSIVE: DESKTOP ===== */
@media (min-width: 900px) {
  .business-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 2px;
  }

  .philosophy-grid {
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: 96px;
  }

  .philosophy-photo {
    order: 2;
  }

  .philosophy-text {
    order: 1;
  }

  .footer-inner {
    flex-direction: row;
    align-items: flex-start;
    justify-content: space-between;
  }

  .footer-copy {
    margin-top: 0;
    align-self: flex-end;
  }
}