*, *::before, *::after { box-sizing: border-box; }
  :root {
    --bg: #ffffff; --fg: #1b1b1b; --muted: #4d4d4d; --card: #ffffff;
    --border: #c7c7c7; --link: #0b57c0; --btn-bg: #0b57c0; --btn-fg: #ffffff;
    --btn-pressed: #a0005f; --focus: #b34700; --error: #b00020;
  }
  @media (prefers-color-scheme: dark) {
    :root {
      --bg: #14171a; --fg: #e9e9e9; --muted: #b3b3b3; --card: #1f2429;
      --border: #4a4a4a; --link: #8ab4ff; --btn-bg: #2f6fd0; --btn-fg: #ffffff;
      --btn-pressed: #c2338a; --focus: #ffb066; --error: #ff9a90;
    }
  }
  body {
    margin: 0;
    background: var(--bg);
    color: var(--fg);
    font: 1rem/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  }
  [hidden] { display: none !important; }
  .visually-hidden {
    position: absolute !important;
    width: 1px; height: 1px;
    padding: 0; margin: -1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
    clip-path: inset(50%);
    white-space: nowrap;
    border: 0;
  }
  .skip-link {
    position: absolute;
    left: 0.5rem;
    top: -4rem;
    z-index: 10;
    background: var(--btn-bg);
    color: var(--btn-fg);
    padding: 0.6rem 1rem;
    border-radius: 0 0 6px 6px;
  }
  .skip-link:focus { top: 0; }
  a { color: var(--link); }
  a:hover { text-decoration-thickness: 2px; }
  :focus-visible {
    outline: 3px solid var(--focus);
    outline-offset: 2px;
    border-radius: 4px;
  }
  header.site { border-bottom: 1px solid var(--border); padding: 0.75rem 1rem; }
  header.site h1 { font-size: 1.25rem; margin: 0 auto; max-width: 40rem; }
  header.site .tagline { font-weight: 400; font-size: 0.9rem; color: var(--muted); }
  main { max-width: 40rem; margin: 0 auto; padding: 1rem; }
  footer.site {
    max-width: 40rem;
    margin: 2rem auto 1rem;
    padding: 0 1rem;
    color: var(--muted);
    font-size: 0.875rem;
  }
  /* Login form */
  .field { margin-bottom: 1rem; }
  label { display: block; font-weight: 600; margin-bottom: 0.25rem; }
  input[type="text"], input[type="password"] {
    width: 100%;
    max-width: 26rem;
    padding: 0.5rem;
    font: inherit;
    border: 2px solid var(--border);
    border-radius: 6px;
    background: var(--card);
    color: var(--fg);
  }
  .hint { color: var(--muted); font-size: 0.875rem; margin: 0.25rem 0 0; max-width: 32rem; }
  .error { color: var(--error); font-weight: 600; min-height: 1.5em; }
  button {
    font: inherit;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    border: 2px solid var(--btn-bg);
    background: var(--btn-bg);
    color: var(--btn-fg);
    cursor: pointer;
  }
  button[disabled] { opacity: 0.6; cursor: default; }
  button.secondary { background: transparent; color: var(--link); border-color: var(--border); }
  /* Feed toolbar */
  .feed-toolbar {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    align-items: center;
    margin-bottom: 1rem;
  }
  .feed-toolbar p { margin: 0; color: var(--muted); }
  .feed-toolbar .spacer { flex: 1; }
  .page-size-label {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    color: var(--muted);
    font-size: 0.9rem;
    font-weight: 400;
    margin: 0;
  }
  .page-size-label input {
    width: 4.5rem;
    padding: 0.3rem 0.4rem;
    font: inherit;
    border: 2px solid var(--border);
    border-radius: 6px;
    background: var(--card);
    color: var(--fg);
  }
  /* Posts */
  #feed { display: grid; gap: 0.75rem; }
  article.post {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 0.9rem 1rem;
  }
  article.post.flash { animation: flash 1.2s ease-out; }
  @keyframes flash {
    0% { box-shadow: 0 0 0 4px var(--focus); }
    100% { box-shadow: none; }
  }
  .post-head { display: flex; gap: 0.6rem; align-items: center; }
  .avatar { width: 44px; height: 44px; border-radius: 50%; background: var(--border); flex: none; }
  .post-author { margin: 0; line-height: 1.3; }
  h2.post-author { font-size: 1.05rem; }
  h3.post-author { font-size: 0.95rem; }
  .post-author .handle { color: var(--muted); font-weight: 400; font-size: 0.875rem; }
  .time-link { font-size: 0.875rem; color: var(--muted); text-decoration: none; }
  .time-link:hover, .time-link:focus-visible { text-decoration: underline; }
  .post-content { margin: 0.6rem 0; white-space: pre-wrap; overflow-wrap: break-word; }
  .counts { color: var(--muted); font-size: 0.875rem; margin: 0.5rem 0 0; }
  .actions { display: flex; gap: 1rem; align-items: center; margin-top: 0.6rem; }
  .like-btn[aria-pressed="true"] { background: var(--btn-pressed); border-color: var(--btn-pressed); }
  .images { display: grid; gap: 0.5rem; margin: 0.5rem 0; }
  .images figure { margin: 0; }
  .images img {
    max-width: 100%;
    max-height: 24rem;
    border-radius: 8px;
    border: 1px solid var(--border);
    display: block;
  }
  .no-alt { color: var(--muted); font-size: 0.8rem; margin: 0.2rem 0 0; font-style: italic; }
  .card-link {
    display: block;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.6rem 0.8rem;
    margin: 0.5rem 0;
    text-decoration: none;
    color: var(--fg);
  }
  .card-link:hover, .card-link:focus-visible { text-decoration: none; border-color: var(--link); }
  .card-title { display: block; font-weight: 600; }
  .card-desc { display: block; color: var(--muted); font-size: 0.875rem; }
  .card-domain { display: block; color: var(--muted); font-size: 0.8rem; margin-top: 0.2rem; }
  .quote {
    border-left: 3px solid var(--border);
    margin: 0.5rem 0;
    padding: 0.2rem 0.8rem;
  }
  .quote-author { margin: 0; font-weight: 600; }
  .quote-text { margin: 0.25rem 0; white-space: pre-wrap; overflow-wrap: break-word; }
  .quote-unavailable { color: var(--muted); font-style: italic; }
  /* Threads: h2 root post, h3 replies in nested ordered lists */
  .thread-tag { margin: 0.4rem 0 0; color: var(--muted); font-size: 0.85rem; }
  .thread-list, .replies { list-style: none; margin: 0.8rem 0 0; padding: 0; }
  .thread-list > li, .replies > li {
    border-left: 3px solid var(--border);
    padding-left: 0.9rem;
    margin-top: 0.9rem;
  }
  .replies { margin-top: 0.5rem; }
  .replies > li { margin-top: 0.7rem; }
  .reply .avatar { width: 32px; height: 32px; }
  .reply-context { margin: 0.3rem 0 0; color: var(--muted); font-size: 0.85rem; }
  .reply-preview { margin: 0.3rem 0; color: var(--muted); }
  .show-more { padding: 0.3rem 0.7rem; font-size: 0.9rem; }
  .reply-full { margin-top: 0.4rem; }
  .more-replies { color: var(--muted); font-size: 0.85rem; margin: 0.3rem 0 0; }
  /* Reposts: the reposter (someone you follow) is the card header */
  .repost-tag {
    display: inline-block;
    margin-left: 0.45rem;
    padding: 0.05rem 0.55rem;
    font-size: 0.75rem;
    font-weight: 600;
    vertical-align: middle;
    color: var(--btn-pressed);
    border: 2px solid var(--btn-pressed);
    border-radius: 999px;
  }
  .repost-frame {
    border-left: 3px solid var(--border);
    margin: 0.6rem 0 0;
    padding: 0.3rem 0 0.3rem 0.9rem;
  }
  .repost-orig { margin: 0 0 0.2rem; font-size: 0.9rem; color: var(--muted); }
  .repost-orig a { font-weight: 600; }
  .load-more-wrap { margin: 1rem 0; text-align: center; }
  @media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation: none !important; transition: none !important; }
  }