:root {
  --bg: #f8ecd9;
  --bg-alt: #f1e0c2;
  --panel: #fffaf1;
  --panel-border: rgba(168, 57, 31, 0.2);
  --gold: #c0472c;
  --gold-soft: #a8391f;
  --gold-bright: #d9573a;
  --heading: #4a2f1c;
  --text: #3b2a1e;
  --text-muted: #6b5646;
  --text-dim: #8a7360;
  --serif: "Yu Mincho", "游明朝", "Hiragino Mincho ProN", serif;
  --sans: "Yu Gothic UI", "Yu Gothic", "游ゴシック", "Hiragino Kaku Gothic ProN", sans-serif;
  --max-width: 880px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background:
    radial-gradient(ellipse at 12% 0%, rgba(192, 71, 44, 0.06), transparent 45%),
    radial-gradient(ellipse at 88% 100%, rgba(192, 71, 44, 0.05), transparent 50%),
    var(--bg);
  color: var(--text);
  font-family: var(--sans);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--gold-bright); text-decoration: none; }
a:hover { color: var(--gold); text-decoration: underline; }

code {
  font-family: "Consolas", "SFMono-Regular", monospace;
  font-size: 0.85em;
  color: var(--text-muted);
  background: rgba(168, 57, 31, 0.07);
  padding: 0.1em 0.35em;
  border-radius: 3px;
  word-break: break-all;
}

/* ---- Hero ---- */

.hero {
  background:
    radial-gradient(ellipse at 50% -10%, rgba(192, 71, 44, 0.10), transparent 60%),
    linear-gradient(180deg, #fdf3e3 0%, var(--bg) 100%);
  border-bottom: 1px solid var(--panel-border);
  padding: 5.5rem 1.5rem 4rem;
}

.hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  text-align: center;
}

.hero-eyebrow {
  letter-spacing: 0.3em;
  font-size: 0.78rem;
  color: var(--gold-soft);
  margin: 0 0 1.1rem;
}

.hero-title {
  font-family: var(--serif);
  font-size: clamp(2.3rem, 6vw, 3.4rem);
  letter-spacing: 0.05em;
  margin: 0;
  color: var(--heading);
  font-weight: 600;
}

.hero-version {
  margin: 0.6rem 0 1.6rem;
  color: var(--text-muted);
  font-size: 1rem;
  letter-spacing: 0.08em;
}

.hero-lead {
  max-width: 34rem;
  margin: 0 auto 2.5rem;
  color: var(--text-muted);
  font-size: 1.02rem;
}

.cta-row {
  display: flex;
  gap: 1.1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 1.4rem;
}

.cta {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  padding: 0.95rem 2.1rem;
  border-radius: 10px;
  min-width: 15rem;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}
.cta:hover { text-decoration: none; transform: translateY(-1px); }

.cta-primary {
  background: linear-gradient(180deg, #d1613f, var(--gold));
  color: #fff8f0;
  border: 1px solid var(--gold-soft);
  box-shadow: 0 4px 16px rgba(168, 57, 31, 0.22);
}
.cta-primary:hover { box-shadow: 0 6px 20px rgba(168, 57, 31, 0.32); color: #fff8f0; }

.cta-secondary {
  background: var(--panel);
  color: var(--gold-soft);
  border: 1px solid var(--panel-border);
}
.cta-secondary:hover { border-color: var(--gold); background: #fdeee3; color: var(--gold); }

.cta-label { font-size: 1.02rem; font-weight: 600; letter-spacing: 0.02em; }
.cta-sub { font-size: 0.74rem; opacity: 0.75; letter-spacing: 0.02em; }

.cta-block { width: 100%; min-width: 0; }

.hero-note {
  color: var(--text-dim);
  font-size: 0.85rem;
  margin: 0;
}

/* ---- Nav ---- */

.toc {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.1rem 1.5rem;
  display: flex;
  gap: 1.6rem;
  flex-wrap: wrap;
  justify-content: center;
  font-size: 0.85rem;
  border-bottom: 1px solid var(--panel-border);
}
.toc a { color: var(--text-muted); }
.toc a:hover { color: var(--gold); }

/* ---- Sections ---- */

.section {
  padding: 3.6rem 1.5rem;
}
.section-alt { background: var(--bg-alt); }

.section-title {
  font-family: var(--serif);
  max-width: var(--max-width);
  margin: 0 auto 1.6rem;
  font-size: 1.5rem;
  letter-spacing: 0.06em;
  color: var(--heading);
  border-bottom: 1px solid var(--panel-border);
  padding-bottom: 0.8rem;
}

.section-body {
  max-width: var(--max-width);
  margin: 0 auto;
  color: var(--text-muted);
}
.section-body p { margin: 0 0 1rem; }

.muted { color: var(--text-dim); }
.small { font-size: 0.82rem; }

.about-notes {
  margin-top: 0.8rem;
  padding-top: 0.8rem;
  border-top: 1px dashed var(--panel-border);
}
.about-notes p { font-size: 0.85rem; }

/* ---- Features ---- */

.feature-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.4rem 2rem;
}
.feature-grid li {
  border-left: 1px solid var(--panel-border);
  padding-left: 1rem;
}
.feature-name {
  display: block;
  color: var(--heading);
  font-weight: 600;
  margin-bottom: 0.3rem;
}
.feature-desc {
  display: block;
  color: var(--text-muted);
  font-size: 0.92rem;
}

/* ---- Download ---- */

.download-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.4rem;
}

.download-card {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 8px;
  padding: 1.8rem 1.6rem;
}
.download-card-primary {
  border-color: var(--gold-soft);
  box-shadow: 0 0 0 1px rgba(168, 57, 31, 0.12) inset;
}
.download-card h3 {
  font-family: var(--serif);
  margin: 0 0 0.4rem;
  color: var(--heading);
  font-size: 1.15rem;
}

.recommend-badge {
  display: inline-block;
  font-size: 0.72rem;
  letter-spacing: 0.05em;
  color: #fff8f0;
  background: var(--gold);
  padding: 0.15rem 0.6rem;
  border-radius: 2px;
  margin: 0 0 1rem;
}
.recommend-badge.muted-badge {
  color: var(--text-dim);
  background: transparent;
  border: 1px solid var(--panel-border);
}

.plain-list, .notice-list, .link-list {
  margin: 0 0 1.2rem;
  padding-left: 1.2rem;
  color: var(--text-muted);
}
.notice-list, .link-list {
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
}
.plain-list li, .notice-list li { margin-bottom: 0.45rem; }

.file-meta {
  margin: 0.7rem 0 0;
  font-size: 0.78rem;
  color: var(--text-dim);
  text-align: center;
}

.hash-details {
  max-width: var(--max-width);
  margin: 1.8rem auto 0;
  border-top: 1px solid var(--panel-border);
  padding-top: 1rem;
}
.hash-details summary {
  cursor: pointer;
  color: var(--text-muted);
  font-size: 0.85rem;
}
.hash-list { margin: 0.8rem 0 0; }
.hash-list dt { color: var(--text-dim); font-size: 0.78rem; margin-top: 0.6rem; }
.hash-list dd { margin: 0.2rem 0 0; }

/* ---- Install / Update steps ---- */

.prereq {
  max-width: var(--max-width);
  margin: 0 auto 1.8rem;
  color: var(--gold-soft);
  background: var(--panel);
  border: 1px solid var(--panel-border);
  padding: 0.9rem 1.1rem;
  border-radius: 8px;
  font-size: 0.92rem;
}

.steps-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.6rem;
}
.steps-block h3 {
  font-family: var(--serif);
  color: var(--heading);
  font-size: 1.05rem;
  margin: 0 0 0.8rem;
}
.steps-list {
  color: var(--text-muted);
  padding-left: 1.3rem;
  margin: 0;
}
.steps-list li { margin-bottom: 0.5rem; }

/* ---- Changelog ---- */

.changelog-entry {
  max-width: var(--max-width);
  margin: 0 auto;
}
.changelog-entry h3 {
  font-family: var(--serif);
  color: var(--heading);
  font-size: 1.1rem;
  margin: 0 0 0.8rem;
}
.changelog-date {
  color: var(--text-dim);
  font-size: 0.8rem;
  font-weight: normal;
  margin-left: 0.6rem;
}

/* ---- Footer ---- */

.site-footer {
  text-align: center;
  padding: 3rem 1.5rem 4rem;
  border-top: 1px solid var(--panel-border);
  color: var(--text-dim);
  font-size: 0.85rem;
}
.site-footer p { margin: 0.3rem 0; }

/* ---- Responsive ---- */

@media (max-width: 680px) {
  .hero { padding: 4rem 1.2rem 3rem; }
  .section { padding: 2.6rem 1.2rem; }
  .feature-grid, .download-grid, .steps-grid {
    grid-template-columns: 1fr;
  }
  .cta { width: 100%; }
  .cta-row { flex-direction: column; align-items: stretch; }
}