/* Reset */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  margin: 0;
  padding: 0;
  scroll-behavior: smooth;
}

/* Global tokens */
:root {
  --aurora-bg:
    radial-gradient(circle at 12% 0%, rgba(210, 228, 255, 0.92), transparent 55%),
    radial-gradient(circle at 88% 0%, rgba(196, 222, 255, 0.88), transparent 55%),
    radial-gradient(circle at 0% 100%, rgba(206, 242, 234, 0.9), transparent 55%),
    radial-gradient(circle at 100% 100%, rgba(255, 229, 214, 0.5), transparent 50%);
}

/* Body */
body {
  margin: 0;
  padding: 0;
  font-family: "Helvetica Neue", system-ui, -apple-system, BlinkMacSystemFont,
    sans-serif;
  background-color: #fafafa;
  color: #111111;
  line-height: 1.85;
  overflow-x: hidden;
  position: relative;
}

/* Aurora background (body 共通レイヤー) */
body::before {
  content: "";
  position: fixed;
  inset: -20vh -20vw;
  background: var(--aurora-bg);
  filter: blur(42px);
  opacity: 0.85;
  pointer-events: none;
  z-index: -1;
  transform: translate3d(0, 0, 0);
  animation: aurora-shift 40s ease-in-out infinite alternate;
}

@keyframes aurora-shift {
  0% {
    transform: translate3d(-4%, -2%, 0) scale(1.02);
  }
  50% {
    transform: translate3d(3%, 3%, 0) scale(1.05);
  }
  100% {
    transform: translate3d(-2%, 4%, 0) scale(1.02);
  }
}

/* Layout shell */
.shell {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  padding: 14px 0 10px;
  background-color: transparent;          /* ボディのオーロラをそのまま活かす */
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
}

/* 2段構成：上ロゴ／下メニュー */
.header-inner {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 8px;
}

.brand {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

/* ロゴは縦横比を維持 */
.brand-mark {
  height: 40px;
  width: auto;
  display: block;
}

/* Navigation */
.primary-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;     /* メニューを中央揃え */
  gap: 10px 22px;
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  white-space: nowrap;
  line-height: 1;
  width: 100%;
}

.primary-nav a {
  color: #222222;
  text-decoration: none;
  padding-bottom: 3px;
  border-bottom: 1px solid transparent;
  transition: color 160ms ease, border-color 160ms ease, opacity 160ms ease;
  opacity: 0.86;
}

.primary-nav a:hover,
.primary-nav a:focus-visible {
  color: #000000;
  border-color: rgba(0, 0, 0, 0.45);
  opacity: 1;
}

/* Main layout */
.main {
  max-width: 720px;
  margin: 0 auto;
  padding: 24px 24px 56px; /* フッタまでの距離をやや詰める */
}

/* Hero */
.hero {
  margin: 24px 0 72px;
  text-align: left;
  scroll-margin-top: 112px;
}

.hero-lead {
  font-size: 1.12rem;
  color: #333333;
  max-width: 640px;
  margin: 0;
  line-height: 1.8;
}

/* Generic sections */
.section {
  margin: 64px 0;
  scroll-margin-top: 112px;
}

.section h2 {
  margin: 0 0 24px;
  font-size: 1.52rem;
  font-weight: 600;
  letter-spacing: 0.03em;
}

.section p {
  margin: 0 0 18px;
  color: #333333;
  max-width: 650px;
  line-height: 1.78;
}

/* 最後のセクションだけ少し余白を詰める */
.section:last-of-type {
  margin-bottom: 8px;
}

/* Lead paragraph */
.lead {
  font-size: 1.05rem;
  font-weight: 500;
  color: #444444;
  margin-bottom: 18px;
  line-height: 1.78;
}

/* --- Section separators（極細フル幅ライン） --- */

.hero + .section,
.section + .section {
  position: relative;
}

.hero + .section::before,
.section + .section::before {
  content: "";
  position: absolute;
  top: -28px;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(
    to right,
    rgba(0, 0, 0, 0.02),
    rgba(0, 0, 0, 0.14),
    rgba(0, 0, 0, 0.02)
  );
  opacity: 0.75;
}

/* ===== セクション画像（5枚のアクセント） ===== */

.section-art {
  margin: 4px 0 24px;
}

.section-art img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 14px;
  box-shadow: 0 18px 45px rgba(0, 0, 0, 0.08);
  mix-blend-mode: multiply;
  opacity: 0.92;
}

.section-art--company img {
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.06);
  opacity: 0.88;
}

/* ===== Entropy Field（Why 内のサブブロック） ===== */

.section--why .entropy-sub {
  margin-top: 32px;
  text-align: center;
}

.section-subheading {
  margin: 0 0 16px;
  font-size: 0.86rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: #555555;
}

.entropy-wrapper {
  display: flex;
  justify-content: center;
  margin-bottom: 18px;
}

.entropy-radial {
  width: 220px;
  height: auto;
  display: block;
}

.entropy-ring {
  fill: none;
  stroke: #111111;
  stroke-width: 1.2;
  opacity: 0.5;
}

.entropy-ring.outer {
  animation: radial-outer 9s ease-in-out infinite;
}

.entropy-ring.mid {
  animation: radial-mid 9s ease-in-out infinite;
}

.entropy-ring.inner {
  animation: radial-inner 9s ease-in-out infinite;
}

.entropy-dot {
  fill: #111111;
  opacity: 0.85;
}

.concept-caption {
  max-width: 480px;
  margin: 0 auto;
  font-size: 0.95rem;
  color: #555555;
  line-height: 1.7;
}

/* Radial animations */
@keyframes radial-outer {
  0%   { r: 80; opacity: 0.50; }
  40%  { r: 70; opacity: 0.45; }
  70%  { r: 60; opacity: 0.35; }
  100% { r: 80; opacity: 0.50; }
}

@keyframes radial-mid {
  0%   { r: 52; opacity: 0.50; }
  40%  { r: 46; opacity: 0.45; }
  70%  { r: 38; opacity: 0.40; }
  100% { r: 52; opacity: 0.50; }
}

@keyframes radial-inner {
  0%   { r: 26; opacity: 0.45; }
  50%  { r: 18; opacity: 0.35; }
  100% { r: 26; opacity: 0.45; }
}

/* Footer */
.site-footer {
  border-top: 1px solid rgba(0, 0, 0, 0.05);
  text-align: center;
  font-size: 0.78rem;
  color: #777777;
  padding: 16px 0 24px;
}

/* Name + Title */
.bio-name-title {
  display: flex;
  gap: 12px;
  align-items: baseline;
  margin-bottom: 6px;
}

.bio-name {
  font-weight: 600;
}

.bio-title {
  font-weight: 600;
  font-size: 0.95rem;
  color: #444444;
  white-space: nowrap;
}

/* Company block */
.company-grid {
  margin: 8px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  row-gap: 0;
  /* 内部罫線はなし */
}

.company-row {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr); /* INDEX列を広めに */
  column-gap: 40px;                              /* INDEXと本文の距離 */
  padding: 14px 0;
}

.company-row:last-child {
  border-bottom: none;
}

/* INDEX：本文と同じフォント＋Bold、右寄せ */
.company-row dt {
  font-size: 0.95rem;
  font-weight: 600;
  text-transform: none;
  letter-spacing: 0;
  color: #333333;
  text-align: right;
}

.company-row dd {
  margin: 0;
  font-size: 0.95rem;
  color: #222222;
  max-width: 540px;
  line-height: 1.82;
}

/* Business domain list */
.business-list {
  margin: 0;
  padding-left: 1.15rem;
  list-style-position: outside;
}

.business-list li {
  margin: 0 0 4px;
}

.business-list li:last-child {
  margin-bottom: 0;
}

/* Accessibility */
a:focus-visible {
  outline: 2px solid rgba(0, 0, 0, 0.6);
  outline-offset: 3px;
  border-radius: 3px;
}

/* Mobile tweaks */
@media (max-width: 768px) {
  .shell {
    padding: 0 16px;
  }

  .site-header {
    padding: 10px 0 6px;
  }

  .header-inner {
    gap: 6px;
  }

  .primary-nav {
    flex-wrap: nowrap;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .primary-nav::-webkit-scrollbar {
    height: 4px;
  }

  .primary-nav::-webkit-scrollbar-thumb {
    background: rgba(0, 0, 0, 0.25);
    border-radius: 999px;
  }

  .main {
    padding: 16px 16px 56px;
  }

  .hero {
    margin-bottom: 56px;
  }

  .section {
    margin: 56px 0;
  }

  .hero + .section::before,
  .section + .section::before {
    top: -22px;
  }

  .section--why .entropy-sub {
    margin-top: 28px;
  }

  .concept-caption {
    padding: 0 8px;
  }

  .bio-name-title {
    flex-direction: column;
    align-items: flex-start;
  }

  .bio-title {
    white-space: normal;
  }

  .company-row {
    grid-template-columns: minmax(0, 1fr);
    row-gap: 4px;
  }

  .company-row dt {
    font-size: 0.9rem;
    text-align: left;  /* スマホでは左寄せで読みやすさ優先 */
  }
}