:root {
      --ink: #06131f;
      --paper: #ffffff;
      --line: #dbe3ea;
      --muted: #4b5563;
      --signal: #0b63ce;
      --font-sans: HelveticaNeue, "Helvetica Neue", Helvetica, Arial, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;
      --font-mono: "SF Mono", "Fira Code", "Fira Mono", Menlo, Consolas, monospace;
      font-family: var(--font-sans);
      color: var(--ink);
      background: var(--paper);
    }
    * { box-sizing: border-box; }
    body { margin: 0; line-height: 1.7; -webkit-font-smoothing: antialiased; }
    main { max-width: 1240px; margin: 0 auto; padding: 28px 20px 72px; }
    .breadcrumb { font-size: 13px; color: var(--muted); margin: 0 0 18px; }
    .breadcrumb a { color: inherit; }
    h1 { margin: 0 0 28px; font-size: clamp(26px, 4vw, 34px); line-height: 1.25; letter-spacing: -0.01em; }

    .video-grid {
      list-style: none;
      margin: 0;
      padding: 0;
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 34px 18px;
    }
    .video-item { display: grid; gap: 6px; align-content: start; scroll-margin-top: 96px; }
    .video-play,
    .video-player {
      position: relative;
      display: block;
      aspect-ratio: 16 / 9;
      overflow: hidden;
      background: #06131f;
    }
    .video-play img {
      display: block;
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.32s ease;
    }
    .video-play::after {
      content: "▶";
      position: absolute;
      left: 50%;
      top: 50%;
      display: grid;
      place-items: center;
      width: 64px;
      height: 44px;
      padding-left: 3px;
      background: rgba(6, 19, 31, 0.86);
      color: #fff;
      font-size: 16px;
      transform: translate(-50%, -50%);
      transition: background 0.2s ease;
    }
    .video-play:hover img,
    .video-play:focus-visible img { transform: scale(1.035); }
    .video-play:hover::after,
    .video-play:focus-visible::after { background: var(--signal); }
    .video-play:focus-visible { outline: 3px solid var(--signal); outline-offset: 3px; }
    .video-player iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
    .video-title {
      margin: 4px 0 0;
      font-size: 15px;
      font-weight: 800;
      line-height: 1.42;
      overflow-wrap: anywhere;
    }
    .video-title a {
      color: var(--ink);
      text-decoration: none;
      display: -webkit-box;
      -webkit-box-orient: vertical;
      -webkit-line-clamp: 2;
      overflow: hidden;
    }
    .video-title a:hover,
    .video-title a:focus-visible { color: var(--signal); outline: none; }
    .video-meta { margin: 0; font-size: 12px; line-height: 1.4; color: var(--muted); }

    .video-links { display: flex; flex-wrap: wrap; gap: 10px 22px; margin: 48px 0 0; padding-top: 18px; border-top: 1px solid var(--line); font-size: 14px; font-weight: 700; }
    .video-links a { color: var(--signal); text-decoration: none; }
    .video-links a:hover,
    .video-links a:focus-visible { text-decoration: underline; text-underline-offset: 3px; }

    @media (max-width: 1020px) {
      .video-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    }
    /* 動画ページはサムネイルと再生が主役。2列ではプレーヤーが小さすぎて再生できないため1列にする */
    @media (max-width: 640px) {
      .video-grid { grid-template-columns: 1fr; gap: 26px; }
    }
    .site-footer {
      display: flex; flex-wrap: wrap; justify-content: space-between; gap: 8px;
      max-width: 1240px; margin: 0 auto; padding: 18px 20px 40px;
      border-top: 1px solid var(--line); font-size: 13px; color: var(--muted);
    }
    .site-footer a { color: inherit; }