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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Helvetica Neue", "Hiragino Sans",
    "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
  line-height: 1.8;
  color: #333;
  background: #fff;
  -webkit-font-smoothing: antialiased;
}

a {
  color: #0071e3;
  text-decoration: none;
  transition: opacity 0.2s;
}

a:hover {
  opacity: 0.7;
}

img {
  max-width: 100%;
  height: auto;
}

/* ── Header ── */
.site-header {
  padding: 1.5rem 2rem;
  border-bottom: 1px solid #f0f0f0;
}

.site-header-inner {
  max-width: 960px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-logo {
  font-size: 1.125rem;
  font-weight: 700;
  color: #111;
  letter-spacing: 0.02em;
}

.site-nav a {
  margin-left: 1.5rem;
  font-size: 0.875rem;
  color: #555;
}

/* ── Hero ── */
.hero {
  text-align: center;
  padding: 5rem 2rem 3rem;
}

.hero h1 {
  font-size: 2rem;
  font-weight: 700;
  color: #111;
  letter-spacing: 0.02em;
}

.hero p {
  margin-top: 1rem;
  font-size: 1.0625rem;
  color: #666;
  max-width: 540px;
  margin-left: auto;
  margin-right: auto;
}

/* ── Section ── */
.section {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 2rem 4rem;
}

.section-title {
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #999;
  margin-bottom: 2rem;
}

/* ── App Cards ── */
.app-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.app-card {
  background: #fafafa;
  border: 1px solid #eee;
  border-radius: 12px;
  padding: 2rem;
  transition: box-shadow 0.2s, transform 0.2s;
}

.app-card:hover {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
  transform: translateY(-2px);
}

.app-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: #111;
  margin-bottom: 0.5rem;
}

.app-card .app-desc {
  font-size: 0.9375rem;
  color: #555;
  margin-bottom: 1.25rem;
}

.store-badges {
  display: flex;
  gap: 0.75rem;
  align-items: center;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.store-badges img {
  height: 44px;
  width: auto;
}

.app-links {
  list-style: none;
  display: flex;
  gap: 1.25rem;
  font-size: 0.8125rem;
}

.app-links a {
  color: #0071e3;
}

/* ── Footer ── */
.site-footer {
  border-top: 1px solid #f0f0f0;
  padding: 2.5rem 2rem;
  text-align: center;
}

.site-footer-inner {
  max-width: 960px;
  margin: 0 auto;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
  font-size: 0.8125rem;
}

.footer-links a {
  color: #666;
}

.footer-copy {
  font-size: 0.75rem;
  color: #999;
}

/* ── Responsive ── */
@media (min-width: 640px) {
  .app-cards {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 900px) {
  .hero h1 {
    font-size: 2.5rem;
  }

  .app-cards {
    grid-template-columns: repeat(3, 1fr);
  }
}