* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 120px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Sans", "Noto Sans JP", sans-serif;
  background: #0a0a0a;
  color: #e5e7eb;
  line-height: 1.8;
  padding: 20px;
  padding-top: 130px;
  -webkit-font-smoothing: antialiased;
}
a { color: #22c55e; text-decoration: none; }
a:hover { text-decoration: underline; }

/* Fixed header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(17,17,17,0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(34,197,94,0.3);
  z-index: 100;
}
.nav-row {
  display: flex;
  justify-content: center;
  gap: 16px;
  padding: 10px 20px 6px;
  flex-wrap: wrap;
  border-bottom: 1px solid rgba(34,197,94,0.1);
}
.nav-row a {
  color: #9ca3af;
  font-weight: 700;
  font-size: 14px;
  padding: 4px 12px;
  border-radius: 6px;
  transition: all 0.2s;
}
.nav-row a.active,
.nav-row a:hover {
  color: #22c55e;
  background: rgba(34,197,94,0.1);
  text-decoration: none;
}
.lang-row {
  display: flex;
  justify-content: center;
  gap: 6px;
  padding: 8px 20px 10px;
  flex-wrap: wrap;
}
.lang-row a {
  color: #9ca3af;
  font-weight: 600;
  font-size: 12px;
  padding: 4px 10px;
  border: 1px solid #333;
  border-radius: 6px;
  transition: all 0.2s;
}
.lang-row a:hover,
.lang-row a.active {
  color: #22c55e;
  border-color: #22c55e;
  background: rgba(34,197,94,0.15);
  text-decoration: none;
}

.container { max-width: 760px; margin: 0 auto; }

.lang-section {
  padding-top: 24px;
  margin-bottom: 56px;
  border-bottom: 2px solid rgba(34,197,94,0.1);
  padding-bottom: 48px;
}
.lang-section:last-of-type { border-bottom: none; }

h1 {
  font-size: 26px;
  color: #fff;
  margin-bottom: 8px;
  line-height: 1.4;
}
.app-icon {
  font-size: 32px;
  margin-right: 10px;
  vertical-align: middle;
}
.updated {
  font-size: 13px;
  color: #6b7280;
  margin-bottom: 28px;
}
h2 {
  font-size: 18px;
  color: #22c55e;
  margin-top: 32px;
  margin-bottom: 10px;
  padding-bottom: 6px;
  border-bottom: 1px solid rgba(34,197,94,0.2);
  line-height: 1.5;
}
h3 {
  font-size: 16px;
  color: #fff;
  margin-top: 20px;
  margin-bottom: 8px;
}
p, li {
  font-size: 14.5px;
  color: #d1d5db;
  margin-bottom: 10px;
}
ul, ol {
  margin-left: 22px;
  margin-bottom: 12px;
}
li { margin-bottom: 4px; }
strong { color: #fff; font-weight: 700; }
code {
  background: #1f2937;
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 13px;
  color: #f3f4f6;
  font-family: Menlo, Consolas, monospace;
}
.note {
  background: rgba(34,197,94,0.05);
  border-left: 3px solid #22c55e;
  padding: 10px 14px;
  margin: 16px 0;
  font-size: 14px;
  border-radius: 4px;
}
.contact-box {
  background: #111827;
  border: 1px solid #374151;
  border-radius: 8px;
  padding: 16px;
  margin: 24px 0;
}
footer {
  text-align: center;
  color: #6b7280;
  font-size: 12px;
  padding: 40px 20px 20px;
  border-top: 1px solid #1f2937;
  margin-top: 40px;
}
footer a { color: #9ca3af; margin: 0 8px; }

/* Hub page cards */
.hub-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin: 40px 0;
}
.hub-card {
  background: #111827;
  border: 1px solid #374151;
  border-radius: 10px;
  padding: 20px;
  text-align: center;
  transition: all 0.2s;
  color: #e5e7eb;
}
.hub-card:hover {
  border-color: #22c55e;
  background: rgba(34,197,94,0.05);
  text-decoration: none;
  transform: translateY(-2px);
}
.hub-card h3 {
  color: #fff;
  margin-top: 8px;
  margin-bottom: 6px;
  font-size: 18px;
}
.hub-card p {
  color: #9ca3af;
  font-size: 13px;
  margin: 0;
}
.hub-icon {
  font-size: 36px;
  margin-bottom: 8px;
}
.intro {
  text-align: center;
  padding: 40px 20px 0;
}
.intro h1 {
  font-size: 34px;
  margin-bottom: 12px;
}
.intro p { color: #9ca3af; }

@media (max-width: 640px) {
  body { padding-top: 130px; padding-left: 14px; padding-right: 14px; }
  h1 { font-size: 22px; }
  h2 { font-size: 16px; }
  p, li { font-size: 14px; }
}