/* ===================================================
   KIYOMINE — Shared Stylesheet  (Redesign 2026)
   =================================================== */

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

:root {
  /* Base: white — NASA precision white */
  --bg:      #ffffff;
  --surface: #f3f6fa;
  --card:    #ffffff;
  --border:  rgba(0, 30, 100, 0.08);

  /* Accents — NASA deep blue palette */
  --accent:  #0d57c8;    /* NASA-like electric deep blue */
  --accent2: #3a80df;    /* Mid blue — sky horizon */
  --accent3: #b87a08;    /* Amber — instrument gold (use sparingly) */

  /* Text */
  --text:    #050f24;
  --muted:   #4e6480;
  --glow:    rgba(13, 87, 200, 0.1);
}

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Inter', 'Noto Sans JP', sans-serif;
  line-height: 1.6;
  overflow-x: hidden;
}

/* ─── NAV ───────────────────────────────────────── */
/* body > nav to avoid matching <nav class="footer-nav"> inside footer */
body > nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 5%;
  height: 52px;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: transform 0.35s ease, background 0.35s ease, border-color 0.35s ease;
}

body > nav.nav--scrolled {
  background: rgba(255, 255, 255, 0.97);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom-color: var(--border);
}

body > nav.nav--hidden {
  transform: translateY(-100%);
}

.nav-logo {
  font-size: 1.1rem;
  font-weight: 800;
  letter-spacing: 0.14em;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
  align-items: center;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.82rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  transition: color 0.2s;
}

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

.nav-cta {
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color: #fff !important;
  padding: 0.38rem 1.1rem;
  border-radius: 5px;
  font-weight: 700 !important;
  font-size: 0.8rem !important;
  transition: opacity 0.2s !important;
}

.nav-cta:hover { opacity: 0.85; }

/* ─── DROPDOWN ───────────────────────────────────── */
.nav-dropdown-parent { position: relative; }

.nav-dropdown-trigger {
  background: none;
  border: none;
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0;
  font-family: inherit;
  transition: color 0.2s;
}

.nav-dropdown-trigger:hover { color: var(--text); }
.dropdown-chevron { transition: transform 0.25s ease; }
.nav-dropdown-parent.is-open .dropdown-chevron { transform: rotate(180deg); }

.nav-dropdown {
  position: absolute;
  top: calc(100% + 14px);
  left: 50%;
  transform: translateX(-50%) translateY(-6px);
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.4rem;
  min-width: 240px;
  box-shadow: 0 8px 32px rgba(0, 20, 80, 0.1), 0 2px 8px rgba(0, 20, 80, 0.05);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  z-index: 200;
}

.nav-dropdown-parent.is-open .nav-dropdown {
  opacity: 1;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}

.nav-dropdown a {
  display: block;
  padding: 0.6rem 0.9rem;
  border-radius: 5px;
  text-decoration: none;
  transition: background 0.15s;
}

.nav-dropdown a:hover { background: var(--surface); }

.dropdown-label {
  display: block;
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--text);
  font-family: 'Noto Sans JP', sans-serif;
}

.dropdown-sub {
  display: block;
  font-size: 0.7rem;
  color: var(--muted);
  letter-spacing: 0.04em;
  margin-top: 0.1rem;
}

/* ─── HAMBURGER ──────────────────────────────────── */
.nav-hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.4rem;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
}

.nav-hamburger span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
  transform-origin: center;
}

.nav-hamburger.is-open span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.nav-hamburger.is-open span:nth-child(2) { opacity: 0; transform: scaleX(0); }
.nav-hamburger.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ─── MOBILE NAV PANEL ───────────────────────────── */
.nav-mobile {
  position: fixed;
  top: 52px;
  left: 0; right: 0;
  background: #fff;
  border-bottom: 1px solid var(--border);
  z-index: 99;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
  box-shadow: 0 8px 24px rgba(0, 20, 80, 0.07);
}

.nav-mobile.is-open { max-height: 420px; }

.nav-mobile > ul {
  list-style: none;
  padding: 0.5rem 5% 1rem;
}

.nav-mobile > ul > li { border-bottom: 1px solid var(--border); }
.nav-mobile > ul > li:last-child { border-bottom: none; }

.nav-mobile > ul > li > a {
  display: block;
  padding: 0.9rem 0;
  color: var(--text);
  text-decoration: none;
  font-size: 0.9rem;
  font-family: 'Noto Sans JP', sans-serif;
  font-weight: 500;
  transition: color 0.2s;
}

.nav-mobile > ul > li > a:hover { color: var(--accent); }

.mobile-accordion-trigger {
  width: 100%;
  background: none;
  border: none;
  padding: 0.9rem 0;
  color: var(--text);
  font-size: 0.9rem;
  font-family: 'Noto Sans JP', sans-serif;
  font-weight: 500;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  text-align: left;
}

.mobile-accordion-trigger svg { transition: transform 0.25s ease; flex-shrink: 0; }
.mobile-accordion.is-open .mobile-accordion-trigger svg { transform: rotate(180deg); }

.mobile-accordion-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.mobile-accordion.is-open .mobile-accordion-body { max-height: 250px; }

.mobile-accordion-body a {
  display: block;
  padding: 0.65rem 1rem;
  color: var(--muted);
  text-decoration: none;
  font-size: 0.85rem;
  font-family: 'Noto Sans JP', sans-serif;
  border-left: 2px solid var(--border);
  margin-left: 0.25rem;
  transition: color 0.2s, border-color 0.2s;
}

.mobile-accordion-body a:hover { color: var(--accent); border-left-color: var(--accent); }

.nav-cta-mobile {
  color: var(--accent) !important;
  font-weight: 700 !important;
}

/* ─── BUTTONS ────────────────────────────────────── */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color: var(--bg);
  font-weight: 700;
  font-size: 0.95rem;
  padding: 0.85rem 2rem;
  border-radius: 7px;
  text-decoration: none;
  letter-spacing: 0.02em;
  transition: transform 0.2s, box-shadow 0.2s;
  box-shadow: 0 0 28px rgba(91, 184, 255, 0.2);
  border: none;
  cursor: pointer;
  font-family: inherit;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 40px rgba(91, 184, 255, 0.35);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: transparent;
  color: var(--text);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 0.85rem 2rem;
  border-radius: 7px;
  text-decoration: none;
  border: 1px solid var(--border);
  transition: border-color 0.2s, background 0.2s;
  cursor: pointer;
  font-family: inherit;
}

.btn-secondary:hover {
  border-color: rgba(91, 184, 255, 0.25);
  background: rgba(91, 184, 255, 0.04);
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: transparent;
  color: var(--accent);
  font-weight: 500;
  font-size: 0.88rem;
  padding: 0.75rem 1.6rem;
  border-radius: 7px;
  text-decoration: none;
  border: 1px solid rgba(91, 184, 255, 0.22);
  transition: border-color 0.2s, background 0.2s;
}

.btn-outline:hover {
  border-color: var(--accent);
  background: rgba(91, 184, 255, 0.05);
}

/* ─── SECTION COMMON ─────────────────────────────── */
section { padding: 6rem 5%; }

.section-tag {
  display: inline-block;
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.75rem;
  opacity: 0.75;
}

.section-title {
  font-size: clamp(1.8rem, 4vw, 3rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1rem;
  font-family: 'Noto Sans JP', sans-serif;
  letter-spacing: -0.02em;
}

.section-desc {
  font-size: 0.95rem;
  color: var(--muted);
  max-width: 520px;
  line-height: 2;
  font-family: 'Noto Sans JP', sans-serif;
}

.section-header { margin-bottom: 3.5rem; }
.section-header.center { text-align: center; }
.section-header.center .section-desc { margin: 0 auto; }

/* ─── CARDS ──────────────────────────────────────── */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2rem;
  transition: border-color 0.3s, transform 0.3s;
  position: relative;
  overflow: hidden;
}

.card:hover { border-color: rgba(91, 184, 255, 0.2); transform: translateY(-4px); }

.card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  opacity: 0;
  transition: opacity 0.3s;
}

.card:hover::before { opacity: 1; }

/* ─── TAGS ───────────────────────────────────────── */
.tag {
  background: rgba(91, 184, 255, 0.06);
  border: 1px solid rgba(91, 184, 255, 0.12);
  color: var(--accent);
  font-size: 0.7rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  border-radius: 3px;
  letter-spacing: 0.04em;
}

/* ─── FOOTER ─────────────────────────────────────── */
footer {
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 3rem 5%;
}

.footer-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-logo {
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-decoration: none;
  display: block;
  margin-bottom: 0.5rem;
}

.footer-tagline {
  font-size: 0.75rem;
  color: var(--muted);
  font-family: 'Noto Sans JP', sans-serif;
  line-height: 1.7;
  opacity: 0.8;
}

.footer-nav {
  display: flex;
  gap: 3rem;
  flex-wrap: wrap;
}

.footer-nav-group h4 {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 0.75rem;
  opacity: 0.6;
}

.footer-nav-group ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-nav-group a {
  font-size: 0.8rem;
  color: var(--muted);
  text-decoration: none;
  transition: color 0.2s;
  font-family: 'Noto Sans JP', sans-serif;
}

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

.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-copy {
  font-size: 0.75rem;
  color: var(--muted);
  opacity: 0.7;
}

.footer-vision {
  font-size: 0.7rem;
  color: var(--muted);
  letter-spacing: 0.1em;
  opacity: 0.45;
}

/* ─── PAGE INNER LAYOUT ──────────────────────────── */
.page-hero {
  padding: 120px 5% 5rem;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}

.page-hero .section-tag { display: block; }

.page-content {
  max-width: 860px;
  margin: 0 auto;
  padding: 4rem 5%;
}

.page-content h2 {
  font-size: 1.4rem;
  font-weight: 800;
  margin: 2.5rem 0 1rem;
  font-family: 'Noto Sans JP', sans-serif;
  color: var(--text);
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border);
}

.page-content h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin: 1.5rem 0 0.6rem;
  font-family: 'Noto Sans JP', sans-serif;
}

.page-content p {
  font-size: 0.92rem;
  color: var(--muted);
  line-height: 2;
  margin-bottom: 1rem;
  font-family: 'Noto Sans JP', sans-serif;
}

.page-content ul, .page-content ol {
  margin: 0.75rem 0 1rem 1.5rem;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 2;
  font-family: 'Noto Sans JP', sans-serif;
}

.page-content a {
  color: var(--accent);
  text-decoration: none;
}

.page-content a:hover { text-decoration: underline; }

.page-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.88rem;
  font-family: 'Noto Sans JP', sans-serif;
}

.page-content th {
  text-align: left;
  padding: 0.75rem 1rem;
  background: var(--card);
  border: 1px solid var(--border);
  color: var(--text);
  font-weight: 600;
  white-space: nowrap;
}

.page-content td {
  padding: 0.75rem 1rem;
  border: 1px solid var(--border);
  color: var(--muted);
  vertical-align: top;
}

.page-content .last-updated {
  font-size: 0.78rem;
  color: var(--muted);
  opacity: 0.7;
  margin-bottom: 2rem;
}

/* ─── ANIMATIONS ─────────────────────────────────── */
.fade-in {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.3; transform: scale(1.5); }
}

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* ─── RESPONSIVE ─────────────────────────────────── */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-hamburger { display: flex; }
  footer { flex-direction: column; }
  .footer-top { flex-direction: column; }
  .footer-bottom { flex-direction: column; text-align: center; }
}