:root {
  --ink: #3f3b37;
  --muted: #6f6a64;
  --surface: #ffffff;
  --shadow: 0 10px 28px rgba(57, 49, 43, 0.09);
  --radius-lg: 28px;
  --radius-md: 20px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Yu Gothic", "Hiragino Sans", "Noto Sans JP", sans-serif;
  color: var(--ink);
  line-height: 1.75;
  background: #f8f6f3;
}

a { color: inherit; }

.site-shell {
  width: min(100% - 32px, 960px);
  margin: 0 auto;
  padding: 22px 0 42px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 22px;
}

.brand {
  color: var(--ink);
  font-weight: 800;
  text-decoration: none;
  letter-spacing: .02em;
}

.topnav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px;
}

.topnav a {
  padding: 7px 11px;
  border-radius: 999px;
  color: var(--muted);
  font-size: .9rem;
  text-decoration: none;
}

.topnav a:hover { background: rgba(255,255,255,.8); }

.hero {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  padding: 42px 34px;
  box-shadow: var(--shadow);
}

.hero::after {
  content: "";
  position: absolute;
  width: 180px;
  height: 180px;
  right: -50px;
  bottom: -80px;
  border-radius: 50%;
  background: rgba(255,255,255,.28);
}

.hero-mark {
  position: relative;
  z-index: 1;
  display: inline-grid;
  place-items: center;
  width: 64px;
  height: 64px;
  margin-bottom: 14px;
  border-radius: 20px;
  background: rgba(255,255,255,.72);
  font-size: 2rem;
}

.hero h1 {
  position: relative;
  z-index: 1;
  margin: 0 0 10px;
  font-size: clamp(1.75rem, 5vw, 2.55rem);
  line-height: 1.3;
}

.hero p {
  position: relative;
  z-index: 1;
  max-width: 700px;
  margin: 0;
  font-size: 1.03rem;
}

.eyebrow {
  display: inline-block;
  margin-bottom: 10px;
  font-size: .84rem;
  font-weight: 800;
  letter-spacing: .08em;
  text-transform: uppercase;
  opacity: .76;
}

.section-title {
  margin: 38px 0 14px;
  font-size: 1.4rem;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.app-card, .content-card {
  background: var(--surface);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow);
}

.app-card {
  display: flex;
  flex-direction: column;
  min-height: 100%;
  padding: 24px;
  border: 2px solid var(--card-border);
}

.app-card .icon {
  display: grid;
  place-items: center;
  width: 54px;
  height: 54px;
  margin-bottom: 14px;
  border-radius: 17px;
  background: var(--card-soft);
  font-size: 1.7rem;
}

.tag {
  align-self: flex-start;
  padding: 5px 11px;
  margin-bottom: 10px;
  border-radius: 999px;
  background: var(--card-soft);
  color: var(--card-ink);
  font-size: .82rem;
  font-weight: 700;
}

.app-card h2 {
  margin: 0 0 8px;
  color: var(--card-ink);
  font-size: 1.28rem;
}

.app-card p {
  flex: 1;
  margin: 0 0 18px;
  color: var(--muted);
}

.egg-card {
  --card-soft: #fff1bf;
  --card-border: #f3e2a0;
  --card-ink: #765100;
  --card-main: #f6d36b;
}

.pitch-card {
  --card-soft: #ddf4df;
  --card-border: #b9ddbd;
  --card-ink: #28633b;
  --card-main: #8dcea0;
}

.bookshelf-card {
  --card-soft: #e2eff8;
  --card-border: #c4dceb;
  --card-ink: #285a78;
  --card-main: #8fc3df;
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 9px 15px;
  border: 1px solid transparent;
  border-radius: 13px;
  font-weight: 800;
  text-decoration: none;
  transition: transform .18s ease, opacity .18s ease;
}

.btn:hover { transform: translateY(-1px); }

.btn-primary {
  background: var(--card-main, var(--accent));
  color: var(--card-ink, var(--accent-ink));
}

.btn-secondary {
  background: rgba(255,255,255,.66);
  border-color: var(--border, var(--card-border));
  color: var(--accent-ink, var(--card-ink));
}

.btn-disabled {
  cursor: default;
  background: #eceae7;
  color: #8c8781;
}

.btn-disabled:hover { transform: none; }

.content-card {
  padding: 26px;
  margin-top: 18px;
  border: 1px solid var(--border, #e9e3dc);
}

.content-card h2, .content-card h3 { margin-top: 0; }
.content-card p:last-child { margin-bottom: 0; }

.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 18px;
}

.feature {
  padding: 18px;
  border-radius: 17px;
  background: var(--soft);
}

.feature strong {
  display: block;
  margin-bottom: 3px;
  color: var(--accent-ink);
}

.notice {
  padding: 16px 18px;
  margin-top: 18px;
  border-left: 5px solid var(--accent);
  border-radius: 12px;
  background: var(--soft);
}

.home-theme {
  --accent: #a790cb;
  --accent-ink: #58466f;
  --soft: #f1ecf8;
  --border: #ded3eb;
  background: #f8f5fa;
}

.home-theme .hero {
  background: linear-gradient(135deg, #e9ddf5, #f9f2dc);
  color: #4f445b;
}

.egg-theme {
  --accent: #f6d36b;
  --accent-ink: #6c4d00;
  --soft: #fff3ca;
  --border: #ecd993;
  background: #fff9e8;
}

.egg-theme .hero {
  background: linear-gradient(135deg, #f6d36b, #f7e7a9);
  color: #5c4300;
}

.pitch-theme {
  --accent: #83c79a;
  --accent-ink: #255c38;
  --soft: #e5f5e7;
  --border: #b9ddbd;
  background: #f1faf2;
}

.pitch-theme .hero {
  background: linear-gradient(135deg, #8fd1a3, #dff2c9);
  color: #214f32;
}

.bookshelf-theme {
  --accent: #83bbd9;
  --accent-ink: #285873;
  --soft: #e5f1f8;
  --border: #bfd8e7;
  background: #f1f7fa;
}

.bookshelf-theme .hero {
  background: linear-gradient(135deg, #8dc5df, #d9e9dd 70%, #dfc19d);
  color: #214f68;
}

footer {
  padding: 36px 0 10px;
  color: var(--muted);
  text-align: center;
  font-size: .9rem;
}

@media (max-width: 760px) {
  .card-grid { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
  .site-shell { width: min(100% - 24px, 960px); padding-top: 14px; }
  .topbar { align-items: flex-start; flex-direction: column; }
  .topnav { justify-content: flex-start; }
  .hero { padding: 30px 22px; }
  .content-card, .app-card { padding: 20px; }
  .button-row { flex-direction: column; }
  .btn { width: 100%; }
}