@media (prefers-color-scheme: dark) {
  :root { color-scheme: dark; }
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Inter", "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
  background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
  color: #f1f5f9;
  line-height: 1.7;
}

.site-header {
  padding: 40px 16px 16px;
  text-align: center;
}
.site-header h1 { margin: 0 0 8px; color: #67e8f9; }
.site-header .app-name { color: #cbd5e1; margin: 0; font-size: 14px; }

.container {
  max-width: 860px;
  margin: 0 auto;
  padding: 24px 16px 40px;
}

.card {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 14px;
  padding: 18px 18px;
  margin: 14px 0;
  backdrop-filter: blur(6px);
}

.card h2 { margin: 0 0 8px; font-size: 18px; color: #e2e8f0; }
.card p { margin: 8px 0; color: #e5e7eb; }
.card ul { margin: 8px 0 8px 18px; padding: 0; }
.card li { margin: 6px 0; color: #e5e7eb; }

a { color: #7dd3fc; text-decoration: none; }
a:hover { text-decoration: underline; }

.site-footer { text-align: center; color: #cbd5e1; padding: 24px 12px 36px; }