:root {
  --bg: #f0f9ff;
  --card: #ffffff;
  --text: #0f172a;
  --muted: #475569;
  --primary: #2dd4bf; /* mint */
  --primary-600: #14b8a6;
  --border: #d9f5ee;
  --surface: #ffffff;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  color: var(--text);
  background: radial-gradient(1200px 800px at 10% -15%, #eaf2ff 0%, #f0f9ff 60%), linear-gradient(180deg, #f0f9ff, #ffffff 60%, #f0f9ff), url('/assets/pattern.svg');
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Noto Sans, "Hiragino Kaku Gothic ProN", "Yu Gothic UI", "Yu Gothic", "Noto Sans JP", "Meiryo", sans-serif;
  line-height: 1.65;
}

.container {
  width: 100%;
  max-width: 960px;
  margin: 0 auto;
  padding: 0 16px;
}

.site-header {
  border-bottom: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(8px);
  position: sticky;
  top: 0;
  z-index: 10;
}
.brand { margin: 0; padding: 12px 0 0; font-size: 26px; }
.brand a { color: inherit; text-decoration: none; }
.brand a:hover { text-decoration: underline; }
.tagline { margin: 0 0 16px; color: var(--muted); }
.lang { font-size: 14px; }
.lang a { color: var(--muted); text-decoration: none; margin-right: 12px; }
.lang a:hover { text-decoration: underline; }

.hero { padding: 32px 0 6px; }
.apps { padding: 4px 0 24px; }

.app-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.card {
  background: #fff;
  border: 1px solid var(--border);
  box-shadow: 0 8px 16px rgba(15, 23, 42, 0.05);
  border-radius: 12px;
  padding: 16px;
}
.card h4 { margin-top: 0; margin-bottom: 8px; }
.card p { margin-top: 0; color: var(--muted); }
.actions { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 8px; }

.button {
  appearance: none;
  border: 1px solid transparent;
  background: var(--primary);
  color: white;
  padding: 10px 14px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  box-shadow: 0 4px 10px rgba(45, 212, 191, 0.18);
}
.button:hover { background: var(--primary-600); box-shadow: 0 6px 14px rgba(20, 184, 166, 0.22); }
.button-secondary { background: #fff; border-color: var(--border); color: var(--text); box-shadow: 0 2px 8px rgba(15, 23, 42, 0.03); border-radius: 8px; }
.button-secondary:hover { border-color: var(--text); }

.link-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.link-list a { color: var(--text); text-decoration: none; }
.link-list a:hover { text-decoration: underline; }

.site-footer { border-top: 1px solid var(--border); padding: 16px 0; margin-top: 24px; color: var(--muted); background: transparent; }

.page { padding: 32px 0; }
.breadcrumb { color: var(--muted); margin-bottom: 16px; }
.breadcrumb a { color: var(--muted); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }