/* ===== 月の刻 / Tsuki no Koku - Common Styles ===== */

:root {
  /* Colors */
  --navy-900: #0a1628;
  --navy-800: #0f1e35;
  --navy-700: #162942;
  --navy-600: #1e3555;
  --navy-500: #2a4568;
  --navy-400: #3d5a7f;
  --ink: #0a1020;

  --gold-100: #f4e4b8;
  --gold-200: #e8d089;
  --gold-300: #d4b866;
  --gold-400: #c9a74d;
  --gold-500: #b8903a;
  --gold-600: #9a7829;

  --paper: #f6efe0;
  --paper-dim: #ebe3d1;
  --text-on-dark: #e9ddc2;
  --text-on-dark-dim: rgba(233, 221, 194, 0.65);
  --text-on-dark-faint: rgba(233, 221, 194, 0.35);

  /* Type */
  --serif-jp: "Noto Serif JP", "Shippori Mincho", "Hiragino Mincho ProN", "Yu Mincho", serif;
  --serif-en: "Cormorant Garamond", "EB Garamond", "Shippori Mincho", serif;
  --sans-jp: "Noto Sans JP", "Hiragino Kaku Gothic ProN", sans-serif;

  /* Layout */
  --nav-h: 72px;
  --max-w: 1280px;
  --gutter: clamp(20px, 4vw, 48px);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--serif-jp);
  font-weight: 300;
  background: var(--navy-900);
  color: var(--text-on-dark);
  line-height: 1.8;
  letter-spacing: 0.04em;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

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

button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }

/* Starfield background */
.starfield {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background:
    radial-gradient(1px 1px at 20% 30%, rgba(244, 228, 184, 0.6), transparent),
    radial-gradient(1px 1px at 70% 20%, rgba(244, 228, 184, 0.4), transparent),
    radial-gradient(1px 1px at 40% 70%, rgba(244, 228, 184, 0.5), transparent),
    radial-gradient(1px 1px at 85% 55%, rgba(244, 228, 184, 0.35), transparent),
    radial-gradient(1px 1px at 15% 85%, rgba(244, 228, 184, 0.45), transparent),
    radial-gradient(1px 1px at 55% 40%, rgba(244, 228, 184, 0.3), transparent),
    radial-gradient(1px 1px at 90% 90%, rgba(244, 228, 184, 0.4), transparent),
    radial-gradient(1px 1px at 30% 50%, rgba(244, 228, 184, 0.25), transparent);
  background-size: 800px 800px;
  opacity: 0.8;
}

.starfield::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at top, transparent 0%, var(--navy-900) 85%);
}

/* ===== Navigation ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-h);
  z-index: 100;
  display: flex;
  align-items: center;
  padding: 0 var(--gutter);
  transition: background 0.4s ease, backdrop-filter 0.4s ease, border-color 0.4s ease;
  border-bottom: 1px solid transparent;
}

.nav.scrolled {
  background: rgba(10, 22, 40, 0.82);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom-color: rgba(212, 184, 102, 0.12);
}

.nav__inner {
  max-width: var(--max-w);
  width: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--gold-200);
}

.brand__mark {
  width: 36px;
  height: 36px;
  flex: none;
}

.brand__name {
  display: flex;
  flex-direction: column;
  line-height: 1;
}

.brand__name .jp {
  font-family: var(--serif-jp);
  font-size: 18px;
  letter-spacing: 0.3em;
  font-weight: 400;
}

.brand__name .en {
  font-family: var(--serif-en);
  font-size: 10px;
  letter-spacing: 0.35em;
  margin-top: 6px;
  color: var(--text-on-dark-dim);
  text-transform: uppercase;
}

.nav__links {
  display: flex;
  gap: 36px;
  align-items: center;
  list-style: none;
}

.nav__links a {
  font-size: 13px;
  letter-spacing: 0.25em;
  color: var(--text-on-dark);
  position: relative;
  padding: 6px 0;
  transition: color 0.3s;
}

.nav__links a:hover,
.nav__links a.active {
  color: var(--gold-200);
}

.nav__links a::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 0;
  width: 0;
  height: 1px;
  background: var(--gold-300);
  transition: width 0.35s ease, left 0.35s ease;
}

.nav__links a:hover::after,
.nav__links a.active::after {
  width: 100%;
  left: 0;
}

.nav__cta {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 10px 22px;
  border: 1px solid rgba(212, 184, 102, 0.5);
  color: var(--gold-200);
  font-size: 12px;
  letter-spacing: 0.3em;
  transition: all 0.3s;
}

.nav__cta:hover {
  background: rgba(212, 184, 102, 0.08);
  border-color: var(--gold-300);
}

.nav__burger {
  display: none;
  width: 28px;
  height: 20px;
  position: relative;
}
.nav__burger span {
  position: absolute;
  left: 0;
  width: 100%;
  height: 1px;
  background: var(--gold-200);
  transition: transform 0.3s, opacity 0.3s;
}
.nav__burger span:nth-child(1) { top: 2px; }
.nav__burger span:nth-child(2) { top: 50%; }
.nav__burger span:nth-child(3) { bottom: 2px; }

.nav.open .nav__burger span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
.nav.open .nav__burger span:nth-child(2) { opacity: 0; }
.nav.open .nav__burger span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

@media (max-width: 860px) {
  .nav__burger { display: block; }
  .nav__links {
    position: fixed;
    inset: var(--nav-h) 0 0 0;
    flex-direction: column;
    justify-content: center;
    gap: 32px;
    background: rgba(10, 22, 40, 0.98);
    backdrop-filter: blur(20px);
    transform: translateX(100%);
    transition: transform 0.4s ease;
  }
  .nav.open .nav__links { transform: translateX(0); }
  .nav__links a { font-size: 16px; }
  .nav__cta { display: none; }
}

/* ===== Sections / Utils ===== */
main { position: relative; z-index: 1; }

section {
  position: relative;
  padding: clamp(80px, 12vw, 160px) var(--gutter);
}

.container {
  max-width: var(--max-w);
  margin: 0 auto;
}

.section-label {
  display: flex;
  align-items: center;
  gap: 16px;
  font-family: var(--serif-en);
  font-size: 12px;
  letter-spacing: 0.4em;
  color: var(--gold-300);
  text-transform: uppercase;
  margin-bottom: 24px;
}

.section-label::before {
  content: "";
  width: 32px;
  height: 1px;
  background: var(--gold-400);
}

.section-title {
  font-family: var(--serif-jp);
  font-weight: 400;
  font-size: clamp(28px, 4.5vw, 48px);
  letter-spacing: 0.2em;
  line-height: 1.6;
  color: var(--paper);
  margin-bottom: 24px;
}

.section-title .accent {
  color: var(--gold-200);
}

.section-lead {
  font-size: 15px;
  line-height: 2.2;
  color: var(--text-on-dark-dim);
  max-width: 640px;
  margin-bottom: 56px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  padding: 16px 36px;
  font-size: 13px;
  letter-spacing: 0.35em;
  border: 1px solid var(--gold-400);
  color: var(--gold-100);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(120deg, transparent, rgba(212, 184, 102, 0.15), transparent);
  transform: translateX(-100%);
  transition: transform 0.6s;
}

.btn:hover::before { transform: translateX(100%); }

.btn:hover {
  background: rgba(212, 184, 102, 0.06);
  border-color: var(--gold-200);
  color: var(--paper);
}

.btn .arrow {
  width: 20px;
  height: 1px;
  background: currentColor;
  position: relative;
  transition: width 0.3s;
}
.btn .arrow::after {
  content: "";
  position: absolute;
  right: 0;
  top: -3px;
  width: 7px;
  height: 7px;
  border-right: 1px solid currentColor;
  border-top: 1px solid currentColor;
  transform: rotate(45deg);
}
.btn:hover .arrow { width: 28px; }

/* Divider with moon */
.moon-divider {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  padding: 48px 0;
  color: var(--gold-400);
}
.moon-divider .line {
  flex: 1;
  max-width: 120px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--gold-500), transparent);
}
.moon-divider svg { width: 18px; height: 18px; }

/* Fade-in on scroll */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 1s ease, transform 1s ease;
}
.reveal.in { opacity: 1; transform: none; }

.reveal.delay-1 { transition-delay: 0.1s; }
.reveal.delay-2 { transition-delay: 0.2s; }
.reveal.delay-3 { transition-delay: 0.3s; }
.reveal.delay-4 { transition-delay: 0.4s; }

/* ===== Footer ===== */
.footer {
  position: relative;
  z-index: 1;
  border-top: 1px solid rgba(212, 184, 102, 0.15);
  padding: 80px var(--gutter) 40px;
  background: var(--navy-800);
}

.footer__inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 48px;
}

.footer__brand .brand__mark { width: 48px; height: 48px; }
.footer__brand .brand__name .jp { font-size: 22px; }
.footer__tagline {
  margin-top: 24px;
  font-size: 13px;
  line-height: 2;
  color: var(--text-on-dark-dim);
  max-width: 320px;
}

.footer__col h4 {
  font-family: var(--serif-en);
  font-size: 11px;
  letter-spacing: 0.4em;
  color: var(--gold-300);
  margin-bottom: 20px;
  text-transform: uppercase;
  font-weight: 400;
}

.footer__col ul { list-style: none; display: flex; flex-direction: column; gap: 12px; }
.footer__col a {
  font-size: 13px;
  color: var(--text-on-dark);
  transition: color 0.3s;
}
.footer__col a:hover { color: var(--gold-200); }

.footer__bottom {
  max-width: var(--max-w);
  margin: 64px auto 0;
  padding-top: 32px;
  border-top: 1px solid rgba(212, 184, 102, 0.1);
  display: flex;
  justify-content: space-between;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--text-on-dark-faint);
}

@media (max-width: 860px) {
  .footer__inner { grid-template-columns: 1fr 1fr; }
  .footer__brand { grid-column: 1 / -1; }
  .footer__bottom { flex-direction: column; gap: 12px; text-align: center; }
}

/* Generic placeholder tile */
.placeholder {
  background:
    linear-gradient(135deg, var(--navy-700), var(--navy-600));
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}
.placeholder::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 50% 50%, rgba(244, 228, 184, 0.12), transparent 60%);
}
.placeholder__label {
  position: relative;
  z-index: 1;
  font-family: var(--serif-en);
  font-size: 11px;
  letter-spacing: 0.4em;
  color: var(--text-on-dark-faint);
  text-transform: uppercase;
}