/* AIまなびラボ 共通スタイル：方眼ノート（ライト）／黒板（ダーク） */
:root {
  --paper: #fbfcf8;
  --grid: #dde8f1;
  --ink: #1f2d4a;
  --muted: #5d6b82;
  --red: #d33f2c;
  --accent: #2c6cb0;
  --key: #ffffff;
  --key-edge: #c5d3e1;
  --soft: #eef3f8;
  --font-num: "Klee One", "Hiragino Mincho ProN", "Yu Mincho", serif;
  --font-ui: "Zen Maru Gothic", "Hiragino Maru Gothic ProN", "Hiragino Sans", "Yu Gothic", sans-serif;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #1f3129; --grid: #2a4035; --ink: #eef2e6; --muted: #a9baa9;
    --red: #ff8f7a; --accent: #f4cf6a; --key: #2b4237; --key-edge: #3e5a4c; --soft: #283d33;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #1f3129; --grid: #2a4035; --ink: #eef2e6; --muted: #a9baa9;
  --red: #ff8f7a; --accent: #f4cf6a; --key: #2b4237; --key-edge: #3e5a4c; --soft: #283d33;
  color-scheme: dark;
}
*, *::before, *::after { box-sizing: border-box; }
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 24px 24px;
  color: var(--ink);
  font-family: var(--font-ui);
  font-size: 16px;
  line-height: 1.75;
}
img { max-width: 100%; }
a { color: var(--accent); }
a:focus-visible, button:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; }
.page { max-width: 720px; margin: 0 auto; padding: 20px 16px 40px; display: grid; gap: 28px; }

.site-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
.logo { font-family: var(--font-num); font-weight: 600; font-size: 1.35rem; color: var(--ink); text-decoration: none; letter-spacing: .04em; }
.logo span { color: var(--red); }
.crumbs { font-size: .85rem; color: var(--muted); }
.crumbs a { color: var(--muted); }

h1, h2, h3 { text-wrap: balance; line-height: 1.4; margin: 0; }
h1 { font-family: var(--font-num); font-weight: 600; font-size: clamp(1.7rem, 6vw, 2.3rem); }
h2 { font-size: 1.3rem; }
h3 { font-size: 1.08rem; }
p { margin: 0; max-width: 65ch; }
.lead { color: var(--muted); }
.stack { display: grid; gap: 12px; }
.panel { min-width: 0; background: var(--paper); border: 2px solid var(--key-edge); border-radius: 16px; padding: 18px 16px; display: grid; gap: 10px; }
ul.list { margin: 0; padding-left: 1.3em; display: grid; gap: 4px; }
.eg { overflow-x: auto; max-width: 100%; font-family: var(--font-num); font-weight: 600; font-size: 1.25rem; background: var(--soft); border-radius: 10px; padding: 8px 12px; font-variant-numeric: tabular-nums; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  background: var(--accent); color: var(--paper); border-radius: 14px; padding: 12px 22px;
  font-weight: 700; font-size: 1.05rem; text-decoration: none; min-height: 50px;
}
.btn.ghost { background: transparent; color: var(--ink); border: 2px solid var(--key-edge); }

/* アプリ一覧 */
.apps { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 14px; }
.app-card { display: grid; grid-template-columns: auto 1fr; gap: 6px 14px; align-items: start; background: var(--key); border: 2px solid var(--key-edge); border-radius: 16px; padding: 16px; color: var(--ink); text-decoration: none; }
.app-card:hover { border-color: var(--accent); }
.app-icon { grid-row: span 2; width: 56px; height: 56px; border-radius: 14px; background: var(--soft); display: grid; place-items: center; font-family: var(--font-num); font-weight: 600; font-size: 1.5rem; color: var(--red); }
.app-card h3 { font-size: 1.1rem; }
.app-card p { font-size: .9rem; color: var(--muted); }
.tag { display: inline-block; font-size: .72rem; font-weight: 700; letter-spacing: .06em; border: 1.5px solid currentColor; border-radius: 999px; padding: 0 8px; margin-left: 6px; color: var(--accent); vertical-align: 2px; }
.app-card.soon { border-style: dashed; background: transparent; }
.app-card.soon .tag { color: var(--muted); }

.grade-links { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 8px; }
.grade-links a { background: var(--key); border: 2px solid var(--key-edge); border-radius: 12px; padding: 10px 12px; text-decoration: none; color: var(--ink); font-weight: 700; }
.grade-links a small { display: block; font-weight: 500; color: var(--muted); font-size: .8rem; }

.table-wrap { overflow-x: auto; }
table { border-collapse: collapse; width: 100%; font-size: .9rem; }
th, td { border: 1px solid var(--key-edge); padding: 6px 10px; text-align: left; vertical-align: top; }
th { background: var(--soft); white-space: nowrap; }

.ad-slot { min-height: 100px; display: grid; place-items: center; }
.ad-placeholder { width: 100%; min-height: 100px; border: 2px dashed var(--key-edge); border-radius: 12px; display: grid; place-items: center; color: var(--muted); font-size: .85rem; background: var(--paper); }

.site-foot { border-top: 2px solid var(--key-edge); padding-top: 18px; display: grid; gap: 8px; font-size: .85rem; color: var(--muted); }
.site-foot nav { display: flex; flex-wrap: wrap; gap: 6px 18px; }
.site-foot a { color: var(--muted); }