/* ============================================================
   BLUE TREE WEB · style.css
   全ページ共通スタイル
   - White base + Royal Blue (#1F3FE0) accent
   - Inter (en) + Noto Sans JP (ja)
   ============================================================ */

:root {
  --color-blue: #033592;        /* イラレ指定の正規ブランドブルー */
  --color-blue-dark: #02266a;   /* ホバー時 */
  --color-blue-soft: #d0d7e8;
  --color-bg: #e3e7ee;          /* ブランドブルーに馴染む青みグレー */
  --color-bg-soft: #d1d6e0;
  --color-bg-blue: #dde1ef;     /* 微調整 */
  --color-text: #101010;
  --color-text-soft: #444444;
  --color-text-mute: #888888;
  --color-line: #ced1da;        /* 背景が濃くなったぶん罫線も濃く */
  --color-line-soft: #dadce4;

  --header-h: 76px;
  --container: 1200px;
  --container-narrow: 880px;

  --ease: cubic-bezier(.4, 0, .2, 1);

  --font-en: 'Inter', system-ui, -apple-system, sans-serif;
  --font-jp: 'Noto Sans JP', system-ui, -apple-system, sans-serif;
  --font-base: 'Inter', 'Noto Sans JP', system-ui, -apple-system, sans-serif;
}

/* ─── Reset & Base ───────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-base);
  font-weight: 400;
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-text);
  background: var(--color-bg);
  letter-spacing: .015em;
}
img, svg { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; transition: color .2s var(--ease); }
ul, ol { margin: 0; padding: 0; list-style: none; }
button { font: inherit; cursor: pointer; background: none; border: none; padding: 0; color: inherit; }
h1, h2, h3, h4, h5, h6 { margin: 0; font-weight: 400; letter-spacing: .02em; line-height: 1.3; }

/* ─── Container ──────────────────────────────────────────── */
.container { max-width: var(--container); margin: 0 auto; padding: 0 32px; }
.container-narrow { max-width: var(--container-narrow); margin: 0 auto; padding: 0 32px; }

/* ─── Section Base ───────────────────────────────────────── */
.section {
  padding: 96px 0;
}
.section--alt { background: var(--color-bg-soft); }
.section--blue { background: var(--color-bg-blue); }

.section-label {
  display: inline-block;
  font-family: var(--font-en);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .35em;
  color: var(--color-blue);
  text-transform: uppercase;
  margin-bottom: 14px;
}
.section-title {
  font-family: var(--font-base);
  font-weight: 300;
  font-size: clamp(28px, 4vw, 40px);
  letter-spacing: .04em;
  line-height: 1.25;
  margin-bottom: 10px;
}
.section-title-jp {
  font-family: var(--font-en);
  font-size: 11px;
  letter-spacing: .3em;
  color: var(--color-text-mute);
  text-transform: uppercase;
  margin-bottom: 32px;
}
.lead {
  font-size: 15px;
  line-height: 2.0;
  color: var(--color-text-soft);
}
.text-center { text-align: center; }
.mt-48 { margin-top: 48px; }

/* ─── Buttons ────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  padding: 16px 32px;
  font-family: var(--font-en);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .25em;
  text-transform: uppercase;
  background: var(--color-blue);
  color: #fff;
  border: 1px solid var(--color-blue);
  transition: all .25s var(--ease);
  white-space: nowrap;
}
.btn:hover { background: var(--color-blue-dark); border-color: var(--color-blue-dark); transform: translateY(-1px); }
.btn .arrow { transition: transform .25s var(--ease); }
.btn:hover .arrow { transform: translateX(4px); }

.btn-outline {
  background: transparent;
  color: var(--color-blue);
}
.btn-outline:hover { background: var(--color-blue); color: #fff; transform: translateY(-1px); }

.btn-ghost {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-text);
}
.btn-ghost:hover { background: var(--color-text); color: #fff; }

/* ─── Header ─────────────────────────────────────────────── */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-h);
  background: rgba(227, 231, 238, .9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-line-soft);
  z-index: 100;
}
.site-header__inner {
  max-width: var(--container);
  height: 100%;
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.site-logo {
  font-family: var(--font-en);
  font-size: 20px;
  font-weight: 500;
  letter-spacing: .04em;
  line-height: 1.1;
  color: var(--color-text);
}
.site-logo .accent { color: var(--color-blue); }
.site-logo small {
  display: block;
  font-size: 8.5px;
  font-weight: 400;
  letter-spacing: .4em;
  color: var(--color-text-mute);
  margin-top: 2px;
}
.nav { display: flex; align-items: center; gap: 36px; font-family: var(--font-en); }
.nav a {
  font-size: 13px;
  font-weight: 500;
  letter-spacing: .15em;
  color: var(--color-text-soft);
  position: relative;
  padding: 6px 0;
}
.nav a:not(.nav-cta)::after {
  content: '';
  position: absolute;
  left: 50%; bottom: 0;
  width: 0;
  height: 1px;
  background: var(--color-blue);
  transition: all .25s var(--ease);
  transform: translateX(-50%);
}
.nav a:hover:not(.nav-cta) { color: var(--color-blue); }
.nav a:hover:not(.nav-cta)::after { width: 100%; }
.nav a.is-active { color: var(--color-blue); }
.nav a.is-active::after { width: 100%; }
.nav a.nav-cta {
  padding: 11px 52px;
  background: transparent;
  color: var(--color-blue) !important;
  border: 1px solid var(--color-blue);
  letter-spacing: .3em;
  font-size: 12px;
  border-radius: 0;
  transition: background .25s var(--ease), color .25s var(--ease);
}
.nav a.nav-cta::after { display: none !important; }
.nav a.nav-cta:hover {
  background: var(--color-blue);
  color: #fff !important;
}

.menu-toggle {
  display: none;
  width: 40px; height: 40px;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}
.menu-toggle span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--color-text);
  transition: all .25s var(--ease);
}
.menu-toggle.is-open span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.menu-toggle.is-open span:nth-child(2) { opacity: 0; }
.menu-toggle.is-open span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

/* ─── Page hero (common to non-index pages) ──────────────── */
.page-hero {
  position: relative;
  padding: calc(var(--header-h) + 80px) 0 80px;
  background: var(--color-bg-soft);
  overflow: hidden;     /* グレー範囲外に木がはみ出ないよう再度トリミング */
}
.page-hero__tree {
  position: absolute;
  right: -4%;
  bottom: -75%;         /* さらに下に */
  width: 880px;
  max-width: 65%;
  opacity: .28;
  pointer-events: none;
  z-index: 1;
}
.page-hero__inner { position: relative; z-index: 2; }
.page-hero h1 {
  font-family: var(--font-base);
  font-size: clamp(40px, 6vw, 64px);
  font-weight: 300;
  letter-spacing: .03em;
  line-height: 1.1;
}
.page-hero .label {
  display: inline-block;
  font-family: var(--font-en);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .4em;
  color: var(--color-blue);
  margin-bottom: 18px;
}
.page-hero .jp { font-size: 12px; letter-spacing: .3em; color: var(--color-text-mute); margin-top: 8px; }

.breadcrumb {
  padding: 18px 0;
  border-bottom: 1px solid var(--color-line);
  font-family: var(--font-en);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--color-text-mute);
}
.breadcrumb b { color: var(--color-text); font-weight: 500; }
.breadcrumb a:hover { color: var(--color-blue); }

/* ─── Reveal (fade-in on scroll) ─────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .8s var(--ease), transform .8s var(--ease);
}
.reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* ─── Footer ─────────────────────────────────────────────── */
.site-footer {
  background: var(--color-bg-soft);
  border-top: 1px solid var(--color-line);
  padding: 64px 0 28px;
  color: var(--color-text-soft);
  font-size: 13px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 56px;
  margin-bottom: 56px;
}
.footer-brand .logo {
  font-family: var(--font-en);
  font-size: 22px;
  font-weight: 500;
  letter-spacing: .04em;
  color: var(--color-text);
  margin-bottom: 18px;
}
.footer-brand .logo .accent { color: var(--color-blue); }
.footer-brand p { line-height: 1.9; font-size: 13px; }
.footer-col h4 {
  font-family: var(--font-en);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .25em;
  color: var(--color-blue);
  text-transform: uppercase;
  margin-bottom: 18px;
}
.footer-col ul li { padding: 5px 0; font-size: 13px; }
.footer-col ul a:hover { color: var(--color-blue); }
.footer-bottom {
  display: flex;
  justify-content: space-between;
  padding-top: 24px;
  border-top: 1px solid var(--color-line);
  font-size: 11px;
  letter-spacing: .15em;
  color: var(--color-text-mute);
}

/* ─── Responsive ─────────────────────────────────────────── */
@media (max-width: 1200px) {
  .container, .container-narrow { padding: 0 24px; }
}

@media (max-width: 880px) {
  :root { --header-h: 64px; }
  .section { padding: 72px 0; }
  .nav { display: none; }
  .menu-toggle { display: flex; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 36px; }

  .nav.is-open {
    display: flex;
    position: fixed;
    top: var(--header-h);
    left: 0; right: 0;
    background: var(--color-bg);
    flex-direction: column;
    gap: 0;
    padding: 20px 32px 40px;
    border-bottom: 1px solid var(--color-line);
    height: calc(100vh - var(--header-h));
    align-items: flex-start;
  }
  .nav.is-open a {
    width: 100%;
    padding: 18px 0;
    font-size: 16px;
    border-bottom: 1px solid var(--color-line-soft);
  }
  .nav.is-open .nav-cta {
    margin-top: 20px;
    padding: 14px 28px;
    border: 0;
    background: var(--color-blue);
  }
}

@media (max-width: 480px) {
  .container, .container-narrow { padding: 0 20px; }
  .section { padding: 56px 0; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; margin-bottom: 36px; }
  .footer-bottom { flex-direction: column; gap: 10px; text-align: left; }
  .site-logo { font-size: 17px; }
  .site-logo small { font-size: 7.5px; letter-spacing: .3em; }
  .btn { padding: 14px 22px; font-size: 11px; letter-spacing: .2em; }
}