body { display: flex; flex-direction: column; min-height: 100vh; }
    main { flex: 1; padding-top: calc(var(--nav-h) + 56px); padding-bottom: 96px; }

    .page-header { margin-bottom: 48px; }
    .page-header-inner { display: flex; flex-direction: column; gap: 20px; }
    .page-eyebrow { display: flex; align-items: center; gap: 14px; }
    .page-eyebrow-line { width: 32px; height: 1px; background: var(--accent-blue); opacity: 0.6; }
    .page-eyebrow-text { font-family: var(--font-mono); font-size: 0.60rem; color: var(--accent-teal); letter-spacing: 0.28em; text-transform: uppercase; }
    .page-desc { font-size: 0.88rem; color: var(--text-1); line-height: 1.85; max-width: 540px; }

    /* ── コントロールバー ── */
    .controls-row {
      display: flex;
      align-items: flex-start;
      gap: 20px;
      flex-wrap: wrap;
      margin-bottom: 40px;
    }

    .filter-group {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
      flex: 1;
    }

    .filter-btn {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      font-family: var(--font-mono);
      font-size: 0.60rem;
      letter-spacing: 0.13em;
      text-transform: uppercase;
      padding: 7px 16px;
      border-radius: 99px;
      border: 1px solid var(--border);
      background: transparent;
      color: var(--text-2);
      cursor: pointer;
      transition: background var(--t), border-color var(--t), color var(--t);
      min-height: 34px;
    }

    .filter-btn:hover { border-color: var(--border-m); color: var(--text-1); }

    .filter-btn.active {
      background: rgba(59,158,255,0.10);
      border-color: rgba(59,158,255,0.40);
      color: var(--accent-blue);
    }

    .filter-btn[data-cat="tech"].active     { background: rgba(59,158,255,0.10); border-color: rgba(59,158,255,0.40); color: #3b9eff; }
    .filter-btn[data-cat="astronomy"].active{ background: rgba(0,229,184,0.10);  border-color: rgba(0,229,184,0.40);  color: #00e5b8; }
    .filter-btn[data-cat="quiz"].active     { background: rgba(139,114,255,0.10);border-color: rgba(139,114,255,0.40);color: #8b72ff; }
    .filter-btn[data-cat="diary"].active    { background: rgba(255,179,64,0.10); border-color: rgba(255,179,64,0.40); color: #ffb340; }
    .filter-btn[data-cat="review"].active   { background: rgba(255,107,107,0.10);border-color: rgba(255,107,107,0.40);color: #ff6b6b; }

    .filter-dot {
      width: 5px; height: 5px;
      border-radius: 50%;
      background: currentColor;
      flex-shrink: 0;
    }

    /* 件数表示 */
    .result-count {
      font-family: var(--font-mono);
      font-size: 0.60rem;
      color: var(--text-2);
      letter-spacing: 0.12em;
      padding-top: 8px;
      white-space: nowrap;
    }

    /* ── レイアウト: メイン + サイドバー ── */
    .blog-layout {
      display: grid;
      grid-template-columns: 1fr 260px;
      gap: 40px;
      align-items: start;
    }

    /* ── 記事グリッド ── */
    .articles-grid {
      display: flex;
      flex-direction: column;
      gap: 20px;
    }

    /* ── 記事カード ── */
    .article-card {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: var(--r-xl);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      padding: 28px 32px;
      display: grid;
      grid-template-columns: 1fr auto;
      gap: 0 24px;
      text-decoration: none;
      color: inherit;
      position: relative;
      overflow: hidden;
      transition:
        border-color var(--t),
        background var(--t),
        transform var(--t) var(--ease),
        box-shadow var(--t);
    }

    .article-card::before {
      content: '';
      position: absolute;
      left: 0; top: 0; bottom: 0;
      width: 2px;
      border-radius: 0 2px 2px 0;
      opacity: 0;
      transition: opacity var(--t);
    }

    .article-card[data-cat="tech"]::before     { background: #3b9eff; }
    .article-card[data-cat="astronomy"]::before{ background: #00e5b8; }
    .article-card[data-cat="quiz"]::before     { background: #8b72ff; }
    .article-card[data-cat="diary"]::before    { background: #ffb340; }
    .article-card[data-cat="review"]::before   { background: #ff6b6b; }

    .article-card:hover {
      border-color: var(--border-m);
      background: var(--bg-card-hover);
      transform: translateX(4px);
      box-shadow: 0 8px 28px rgba(0,0,0,0.28);
    }

    .article-card:hover::before { opacity: 1; }

    .article-card-body {
      display: flex;
      flex-direction: column;
      gap: 10px;
      min-width: 0;
    }

    .article-card-meta {
      display: flex;
      align-items: center;
      gap: 12px;
      flex-wrap: wrap;
    }

    .article-cat-badge {
      font-family: var(--font-mono);
      font-size: 0.54rem;
      letter-spacing: 0.16em;
      text-transform: uppercase;
      padding: 3px 10px;
      border-radius: 99px;
      border: 1px solid;
    }

    .article-cat-badge[data-cat="tech"]     { color: #3b9eff; border-color: rgba(59,158,255,0.28); background: rgba(59,158,255,0.06); }
    .article-cat-badge[data-cat="astronomy"]{ color: #00e5b8; border-color: rgba(0,229,184,0.28);  background: rgba(0,229,184,0.06); }
    .article-cat-badge[data-cat="quiz"]     { color: #8b72ff; border-color: rgba(139,114,255,0.28);background: rgba(139,114,255,0.06); }
    .article-cat-badge[data-cat="diary"]    { color: #ffb340; border-color: rgba(255,179,64,0.28); background: rgba(255,179,64,0.06); }
    .article-cat-badge[data-cat="review"]   { color: #ff6b6b; border-color: rgba(255,107,107,0.28);background: rgba(255,107,107,0.06); }

    .article-date {
      font-family: var(--font-mono);
      font-size: 0.58rem;
      color: var(--text-2);
      letter-spacing: 0.10em;
    }

    .article-reading-time {
      font-family: var(--font-mono);
      font-size: 0.56rem;
      color: var(--text-2);
      letter-spacing: 0.08em;
    }

    .article-card-title {
      font-family: var(--font-display);
      font-size: 1.08rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      color: var(--text-0);
      line-height: 1.3;
      transition: color var(--t);
    }

    .article-card:hover .article-card-title { color: var(--accent-blue); }

    .article-card-excerpt {
      font-size: 0.80rem;
      color: var(--text-1);
      line-height: 1.78;
      display: -webkit-box;
      -webkit-line-clamp: 2;
      -webkit-box-orient: vertical;
      overflow: hidden;
    }

    .article-tags {
      display: flex;
      flex-wrap: wrap;
      gap: 5px;
      margin-top: 2px;
    }

    .article-tag {
      font-family: var(--font-mono);
      font-size: 0.54rem;
      letter-spacing: 0.09em;
      color: var(--text-2);
      border: 1px solid var(--border);
      border-radius: 4px;
      padding: 2px 7px;
      transition: border-color var(--t), color var(--t);
    }

    .article-card:hover .article-tag { border-color: var(--border-m); color: var(--text-1); }

    /* カード右：アロー */
    .article-card-arrow {
      display: flex;
      align-items: center;
      align-self: center;
      color: var(--text-2);
      flex-shrink: 0;
      transition: color var(--t), transform var(--t) var(--ease-spring);
    }

    .article-card:hover .article-card-arrow {
      color: var(--accent-blue);
      transform: translateX(4px);
    }

    .article-card-arrow svg { width: 18px; height: 18px; }

    /* ── 注目記事（featured） ── */
    .article-card.featured {
      grid-template-columns: 1fr;
      border-color: var(--border-m);
      background: rgba(5,16,40,0.88);
    }

    .featured-label {
      font-family: var(--font-mono);
      font-size: 0.52rem;
      letter-spacing: 0.22em;
      text-transform: uppercase;
      color: var(--accent-amber);
      border: 1px solid rgba(255,179,64,0.28);
      background: rgba(255,179,64,0.06);
      border-radius: 99px;
      padding: 3px 10px;
      display: inline-flex;
      align-items: center;
      gap: 5px;
      align-self: flex-start;
      margin-bottom: 4px;
    }

    .featured-label-dot {
      width: 4px; height: 4px;
      border-radius: 50%;
      background: var(--accent-amber);
      animation: statusPulse 2s ease-in-out infinite;
    }

    @keyframes statusPulse {
      0%,100%{ opacity: 1; } 50%{ opacity: 0.3; }
    }

    .article-card.featured .article-card-title { font-size: 1.22rem; }
    .article-card.featured .article-card-excerpt { -webkit-line-clamp: 3; }

    /* ── 空の状態 ── */
    .empty-state {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 16px;
      padding: 80px 32px;
      text-align: center;
    }

    .empty-icon { width: 52px; height: 52px; color: var(--text-2); opacity: 0.45; }
    .empty-title { font-family: var(--font-display); font-size: 1.05rem; font-weight: 700; color: var(--text-1); }
    .empty-desc { font-size: 0.78rem; color: var(--text-2); line-height: 1.75; max-width: 320px; }
    .empty-badge {
      font-family: var(--font-mono); font-size: 0.58rem; color: var(--accent-teal);
      border: 1px solid rgba(0,229,184,0.25); background: rgba(0,229,184,0.06);
      border-radius: 99px; padding: 5px 14px; letter-spacing: 0.14em; text-transform: uppercase;
    }

    /* ── サイドバー ── */
    .sidebar { display: flex; flex-direction: column; gap: 24px; position: sticky; top: calc(var(--nav-h) + 24px); }

    .sidebar-card {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: var(--r-lg);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      padding: 22px;
    }

    .sidebar-title {
      font-family: var(--font-mono);
      font-size: 0.60rem;
      color: var(--accent-teal);
      letter-spacing: 0.22em;
      text-transform: uppercase;
      margin-bottom: 16px;
      padding-bottom: 10px;
      border-bottom: 1px solid var(--border);
    }

    /* カテゴリ一覧 */
    .sidebar-cats { display: flex; flex-direction: column; gap: 4px; }

    .sidebar-cat-btn {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 8px 12px;
      border-radius: var(--r-sm);
      border: none;
      background: transparent;
      color: var(--text-1);
      font-family: var(--font-mono);
      font-size: 0.64rem;
      letter-spacing: 0.10em;
      cursor: pointer;
      transition: background var(--t), color var(--t);
      text-align: left;
      width: 100%;
    }

    .sidebar-cat-btn:hover { background: rgba(59,158,255,0.06); color: var(--text-0); }

    .sidebar-cat-btn.active {
      background: rgba(59,158,255,0.10);
      color: var(--accent-blue);
    }

    .sidebar-cat-count {
      font-family: var(--font-mono);
      font-size: 0.56rem;
      color: var(--text-2);
      background: rgba(255,255,255,0.04);
      border: 1px solid var(--border);
      border-radius: 99px;
      padding: 1px 8px;
    }

    /* タグクラウド */
    .tag-cloud { display: flex; flex-wrap: wrap; gap: 5px; }

    .tag-cloud-btn {
      font-family: var(--font-mono);
      font-size: 0.56rem;
      letter-spacing: 0.09em;
      padding: 4px 10px;
      border-radius: 4px;
      border: 1px solid var(--border);
      background: transparent;
      color: var(--text-2);
      cursor: pointer;
      transition: border-color var(--t), color var(--t), background var(--t);
    }

    .tag-cloud-btn:hover { border-color: var(--border-m); color: var(--text-1); }

    .tag-cloud-btn.active {
      border-color: rgba(59,158,255,0.40);
      color: var(--accent-blue);
      background: rgba(59,158,255,0.06);
    }

    /* アーカイブ */
    .archive-list { display: flex; flex-direction: column; gap: 0; }

    .archive-item {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 8px 0;
      border-bottom: 1px solid var(--border);
      font-family: var(--font-mono);
      font-size: 0.62rem;
      color: var(--text-1);
      cursor: pointer;
      transition: color var(--t);
      background: none;
      border-top: none;
      border-left: none;
      border-right: none;
      text-align: left;
      width: 100%;
    }

    .archive-item:last-child { border-bottom: none; }
    .archive-item:hover { color: var(--accent-blue); }

    .archive-count {
      font-family: var(--font-mono);
      font-size: 0.56rem;
      color: var(--text-2);
    }

    /* ── ローディング ── */
    .loading-state {
      display: flex; align-items: center; justify-content: center;
      gap: 10px; padding: 80px 0;
      font-family: var(--font-mono); font-size: 0.70rem;
      color: var(--text-2); letter-spacing: 0.14em;
    }

    .loading-dot {
      width: 6px; height: 6px; border-radius: 50%;
      background: var(--accent-blue);
      animation: loadingPulse 1.2s ease-in-out infinite;
    }

    .loading-dot:nth-child(2){ animation-delay: 0.2s; }
    .loading-dot:nth-child(3){ animation-delay: 0.4s; }

    @keyframes loadingPulse {
      0%,80%,100%{ transform: scale(0.5); opacity: 0.3; }
      40%        { transform: scale(1.0); opacity: 1.0; }
    }

    /* ── ページネーション ── */
    .pagination {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      margin-top: 40px;
    }

    .page-btn {
      width: 36px; height: 36px;
      border-radius: var(--r-sm);
      border: 1px solid var(--border);
      background: transparent;
      color: var(--text-2);
      font-family: var(--font-mono);
      font-size: 0.65rem;
      cursor: pointer;
      transition: border-color var(--t), color var(--t), background var(--t);
      display: flex; align-items: center; justify-content: center;
    }

    .page-btn:hover { border-color: var(--border-m); color: var(--text-1); }
    .page-btn.active { border-color: rgba(59,158,255,0.45); color: var(--accent-blue); background: rgba(59,158,255,0.08); }
    .page-btn:disabled { opacity: 0.3; cursor: default; }

    /* ── 戻るリンク ── */
    .back-to-lab {
      display: inline-flex; align-items: center; gap: 10px;
      font-family: var(--font-mono); font-size: 0.62rem;
      color: var(--text-2); letter-spacing: 0.14em;
      text-transform: uppercase; text-decoration: none;
      transition: color var(--t); margin-top: 56px;
    }

    .back-to-lab:hover { color: var(--accent-blue); }
    .back-to-lab svg { width: 14px; height: 14px; transform: rotate(180deg); }

    /* ── レスポンシブ ── */
    @media (max-width: 900px) {
      .blog-layout { grid-template-columns: 1fr; }
      .sidebar { position: static; }
    }

    @media (max-width: 760px) {
      main { padding-top: calc(var(--nav-h) + 36px); }
      .article-card { padding: 20px; gap: 0 16px; }
      .controls-row { flex-direction: column; gap: 12px; }
    }

    @media (max-width: 520px) {
      .article-card { grid-template-columns: 1fr; }
      .article-card-arrow { display: none; }
    }

    .error-state {
      display: none;
      text-align: center;
      padding: 80px 0;
    }

    .error-state-text {
      max-width: 420px;
      margin: 0 auto 18px;
      color: var(--text-1);
      font-size: var(--fs-xs);
      line-height: 1.8;
    }

    .retry-btn {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 10px 22px;
      border-radius: var(--r-sm);
      border: 1px solid var(--border-m);
      background: rgba(75,169,255,0.08);
      color: var(--accent-blue);
      font-family: var(--font-mono);
      font-size: var(--fs-xs);
      letter-spacing: var(--ls-wide);
      cursor: pointer;
      transition: background var(--t), border-color var(--t), transform var(--t) var(--ease-spring);
      min-height: 42px;
    }

    .retry-btn:hover {
      background: rgba(75,169,255,0.16);
      border-color: var(--accent-blue);
      transform: translateY(-2px);
    }

    .retry-btn svg { width: 14px; height: 14px; }