:root {
  --bg: #f6f7fb; --card: #ffffff; --ink: #18213a; --muted: #5b6478; --line: #e2e6ef;
  --brand: #1d3a6e; --accent: #ffb81c; --link: #1f5fbf;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #10141f; --card: #19202f; --ink: #e8ecf4; --muted: #a3acc0; --line: #2a3346;
          --brand: #2b4f8f; --link: #8ab4ff; }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink);
       font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
a { color: var(--link); }
.wrap { max-width: 1080px; margin: 0 auto; padding: 0 16px; }
h1 { font-size: clamp(1.6rem, 4vw, 2.3rem); line-height: 1.2; margin: 28px 0 12px; }
h2 { font-size: 1.35rem; margin: 36px 0 14px; }
h2 a { color: inherit; text-decoration: none; }
.count { color: var(--muted); font-size: .9rem; font-weight: 400; }
.top { background: var(--brand); color: #fff; }
.top-row { display: flex; align-items: center; justify-content: space-between; gap: 12px; min-height: 60px; flex-wrap: wrap; }
.brand { color: #fff; text-decoration: none; font-weight: 700; font-size: 1.1rem; }
.mark { background: var(--accent); color: var(--brand); border-radius: 6px; padding: 2px 6px; margin-right: 4px; }
.top nav { display: flex; align-items: center; gap: 16px; }
.top nav a { color: #fff; text-decoration: none; }
.btn { display: inline-block; background: var(--accent); color: #1a1a1a !important; text-decoration: none;
       font-weight: 600; padding: 8px 16px; border-radius: 8px; }
.btn-big { padding: 12px 22px; font-size: 1.05rem; }
.btn-ghost { background: transparent; color: var(--link) !important; border: 1px solid var(--line); }
.hero { padding: 24px 0 8px; }
.hero p { max-width: 640px; color: var(--muted); }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 16px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 10px; overflow: hidden;
        text-decoration: none; color: var(--ink); display: flex; flex-direction: column; }
.card:hover { border-color: var(--link); }
.card img { width: 100%; height: auto; aspect-ratio: 16/9; object-fit: cover; display: block; }
.card-title { padding: 10px 12px 14px; font-weight: 600; font-size: .95rem; line-height: 1.35; }
.crumbs { color: var(--muted); font-size: .9rem; margin: 20px 0 0; }
.video { max-width: 820px; }
.yt { position: relative; aspect-ratio: 16/9; background: #000; border-radius: 10px; overflow: hidden; cursor: pointer; }
.yt img, .yt iframe { width: 100%; height: 100%; object-fit: cover; border: 0; display: block; }
.play { position: absolute; inset: 0; margin: auto; width: 76px; height: 54px; border: 0; border-radius: 14px;
        background: #e00 url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path fill="white" d="M8 5v14l11-7z"/></svg>') center/34px no-repeat; cursor: pointer; }
.actions { display: flex; gap: 10px; flex-wrap: wrap; margin: 14px 0; }
.lead { font-size: 1.05rem; }
.chapter h3 { margin: 22px 0 6px; }
.chapter li { margin: 6px 0; }
.topics { list-style: none; padding: 0; }
.topics li { padding: 12px 0; border-bottom: 1px solid var(--line); }
.foot { margin-top: 56px; padding: 24px 0; border-top: 1px solid var(--line); color: var(--muted); font-size: .95rem; }
.small { font-size: .85rem; }
@media (max-width: 560px) {
  .top nav { gap: 12px; font-size: .95rem; }
  .top nav .btn { padding: 6px 12px; }
  .brand { font-size: 1rem; }
}
.kit-box { background: var(--card); border: 2px solid var(--accent); border-radius: 12px; padding: 4px 20px 18px; margin: 24px 0; }
.kit-box h2 { margin-top: 16px; }
.signup { display: grid; gap: 10px; max-width: 520px; margin: 12px 0; }
.signup input[type=email] { font: inherit; padding: 10px 12px; border: 1px solid var(--line); border-radius: 8px;
                            background: var(--card); color: var(--ink); }
.signup .btn { border: 0; font: inherit; font-weight: 600; cursor: pointer; justify-self: start; }
.consent { font-size: .9rem; color: var(--muted); }
.consent input { margin-right: 6px; }
.trap, .sr { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.kit-list { padding-left: 20px; }
.error { color: #b42318; font-weight: 600; }
.downloads { list-style: none; padding: 0; display: grid; gap: 10px; max-width: 420px; }
.tools-box { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 4px 20px 12px; margin: 28px 0; }
.tools-box ul { padding-left: 20px; }
.tools-box li { margin: 8px 0; }