:root {
  --bg: #10141b;
  --bg-elevated: #171d27;
  --bg-elevated-2: #1e2531;
  --line: rgba(244, 239, 228, 0.10);
  --text: #f4efe4;
  --text-soft: #b7bfcc;
  --text-faint: #7c8494;
  --accent: #e6b73d;
  --accent-soft: #f2cc6b;
  --accent-ink: #211705;
  --radius: 14px;
  --nav-h: 72px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.001s !important; transition-duration: 0.001s !important; }
}
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: "Noto Sans JP", sans-serif;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; }

.skip-link {
  position: fixed;
  top: -3em;
  left: 1em;
  z-index: 100;
  background: var(--accent);
  color: var(--accent-ink);
  font-weight: 700;
  padding: 0.6em 1em;
  border-radius: 0 0 8px 8px;
  transition: top 0.2s ease;
}
.skip-link:focus { top: 0; }
a:focus-visible, button:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}

/* ---------- header / nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  background: rgba(16, 20, 27, 0.72);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  width: 100%;
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 clamp(16px, 4vw, 40px);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}
.brand {
  display: flex;
  align-items: center;
  gap: 0.7em;
  text-decoration: none;
  min-width: 0;
}
.brand-logo { width: 40px; height: 40px; flex: none; }
.brand-name {
  font-weight: 700;
  font-size: 0.95rem;
  line-height: 1.25;
  color: var(--text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 8px;
  width: 42px;
  height: 42px;
  padding: 0;
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
}
.nav-toggle-bar {
  width: 20px;
  height: 2px;
  background: var(--text);
  transition: transform 0.25s ease, opacity 0.25s ease;
}
.nav-toggle[aria-expanded="true"] .bar-1 { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .bar-2 { opacity: 0; }
.nav-toggle[aria-expanded="true"] .bar-3 { transform: translateY(-6px) rotate(-45deg); }

nav#primary-nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  align-items: center;
  gap: 0.25rem;
}
nav#primary-nav a {
  display: flex;
  align-items: center;
  gap: 0.4em;
  text-decoration: none;
  color: var(--text-soft);
  font-weight: 500;
  font-size: 0.92rem;
  padding: 0.6em 0.9em;
  border-radius: 8px;
  transition: color 0.2s ease, background-color 0.2s ease;
  white-space: nowrap;
}
nav#primary-nav a:hover { color: var(--text); background: var(--bg-elevated); }

/* ---------- page intro ---------- */
.tile-page {
  max-width: 1000px;
  margin: 0 auto;
  padding: clamp(40px, 7vw, 72px) clamp(16px, 4vw, 40px) clamp(64px, 9vw, 100px);
}
.tile-intro { text-align: center; margin-bottom: clamp(32px, 6vw, 56px); }
.tile-title {
  font-family: "Audiowide", sans-serif;
  font-weight: 400;
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  line-height: 1.3;
  margin: 0 0 0.7em;
}
.tile-lead {
  max-width: 60ch;
  margin: 0 auto 0.9em;
  color: var(--text);
  font-size: clamp(0.92rem, 1.6vw, 1.02rem);
}
.tile-note {
  max-width: 60ch;
  margin: 0 auto;
  color: var(--text-faint);
  font-size: 0.85rem;
}

.tile-cta-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.7em;
  margin-top: 1.2em;
}
.tile-guide-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.55em;
  padding: 0.65em 1.2em;
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--text);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 500;
  transition: border-color 0.2s ease, background-color 0.2s ease, transform 0.2s ease;
}
.tile-guide-cta i:first-child { color: var(--accent); }
.tile-guide-cta i:last-child { color: var(--text-faint); transition: transform 0.2s ease, color 0.2s ease; }
.tile-guide-cta:hover {
  border-color: rgba(230, 183, 61, 0.4);
  background: var(--bg-elevated-2);
  transform: translateY(-1px);
}
.tile-guide-cta:hover i:last-child { transform: translateX(3px); color: var(--accent); }

/* ---------- tile stage ---------- */
.tile-stage { display: flex; flex-direction: column; align-items: center; }
.tile-grid {
  container-type: inline-size;
  width: min(88vw, 68dvh, 720px);
  aspect-ratio: 1 / 1;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-template-rows: repeat(4, 1fr);
  background-image: linear-gradient(rgba(16, 20, 27, 0.18), rgba(16, 20, 27, 0.18)), url("assets/thumb.jpg");
  background-size: cover;
  background-position: center;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  box-shadow: 0 24px 60px -24px rgba(0, 0, 0, 0.6);
}
.tile {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  border: 1px solid rgba(244, 239, 228, 0.16);
  background: rgba(16, 20, 27, 0.14);
  color: var(--text);
  font-family: "Audiowide", sans-serif;
  font-size: clamp(0.7rem, 6.5cqw, 1.9rem);
  text-shadow: 0 1px 6px rgba(0, 0, 0, 0.7);
  cursor: pointer;
  transition: background-color 0.18s ease, border-color 0.18s ease;
}
.tile:hover, .tile:focus-visible {
  background: rgba(230, 183, 61, 0.32);
  border-color: var(--accent-soft);
  color: var(--accent-ink);
  outline: none;
}
.tile:active { background: rgba(230, 183, 61, 0.55); }
.tile.is-tapped { background: rgba(230, 183, 61, 0.55); }

.tile-hint {
  margin-top: 1.1em;
  color: var(--text-faint);
  font-size: 0.85rem;
  text-align: center;
}

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 1.6rem clamp(16px, 4vw, 40px) 2.2rem;
}
.footer-inner {
  max-width: 1320px;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  color: var(--text-soft);
  font-size: 0.82rem;
}

/* ---------- responsive ---------- */
@media (max-width: 720px) {
  .nav-toggle { display: flex; }
  nav#primary-nav {
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: rgba(16, 20, 27, 0.98);
    border-bottom: 1px solid var(--line);
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease, transform 0.2s ease;
  }
  nav#primary-nav.open { opacity: 1; transform: translateY(0); pointer-events: auto; }
  nav#primary-nav ul {
    flex-direction: column;
    align-items: stretch;
    padding: 0.6rem clamp(16px, 4vw, 40px) 1rem;
    gap: 0.2rem;
  }
  nav#primary-nav a { padding: 0.9em 0.6em; font-size: 1rem; }
  .brand-name { font-size: 0.82rem; }
}