@layer components {
  :root[data-theme="theme"] .timeline-shell {
    display: grid;
    grid-template-columns: 20rem minmax(0, 1fr);
    min-height: 100vh;
    background: var(--surface);
  }
  :root[data-theme="theme"] .timeline-sidebar {
    position: sticky;
    top: 0;
    display: flex;
    flex-direction: column;
    align-self: start;
    height: 100vh;
    padding: var(--space-6);
    overflow: hidden;
    background: var(--rail);
    color: var(--rail-text);
  }
  :root[data-theme="theme"] .timeline-sidebar h1 { color: var(--rail-text); font-size: var(--fs-xl); }
  :root[data-theme="theme"] .timeline-nav--rail {
    display: grid;
    min-height: 0;
    margin-top: var(--space-5);
    overflow: auto;
    flex: 1;
    align-content: start;
    gap: var(--space-3);
  }
  :root[data-theme="theme"] .timeline-nav--rail h2 { color: var(--rail-text); font-size: var(--fs-md); }
  :root[data-theme="theme"] .timeline-nav__row--rail { display: grid; gap: var(--space-1); }
  :root[data-theme="theme"] .timeline-nav__button {
    min-height: 2.5rem;
    color: var(--text-soft);
    font-weight: 700;
    cursor: pointer;
  }
  :root[data-theme="theme"] .timeline-nav__row--rail .timeline-nav__button {
    width: 100%;
    padding: var(--space-2) var(--space-3);
    border: 1px solid transparent;
    border-radius: var(--radius-small);
    background: transparent;
    color: var(--rail-text-soft);
    text-align: left;
  }
  :root[data-theme="theme"] .timeline-nav__row--rail .timeline-nav__button:hover {
    border-color: var(--rail-line);
    color: var(--rail-text);
  }
  :root[data-theme="theme"] .timeline-nav__row--rail .timeline-nav__button.is-active {
    border-color: #2cc3bf;
    background: var(--accent);
    color: #fff;
  }
  :root[data-theme="theme"] .timeline-sidebar__back {
    display: flex;
    align-items: center;
    min-height: 3rem;
    margin-top: auto;
    color: var(--rail-text);
    font-weight: 750;
    text-decoration: none;
  }
  :root[data-theme="theme"] .timeline-sidebar__back::before { margin-right: var(--space-2); color: #60ded8; content: "←"; }
  :root[data-theme="theme"] .timeline-nav-compact { display: none; }

  :root[data-theme="theme"] .timeline-workspace {
    min-width: 0;
    padding: var(--space-7);
    background: var(--surface);
  }
  :root[data-theme="theme"] .timeline {
    display: grid;
    gap: var(--space-7);
    width: min(70rem, 100%);
    margin: 0 auto;
  }
  :root[data-theme="theme"] .timeline-period,
  :root[data-theme="theme"] .timeline-period__moments {
    display: grid;
    gap: var(--space-5);
    margin: 0;
    padding: 0;
    list-style: none;
  }
  :root[data-theme="theme"] .timeline-period { padding-bottom: var(--space-7); scroll-margin-top: var(--space-4); }
  :root[data-theme="theme"] .timeline-period__header {
    display: grid;
    gap: var(--space-2);
    padding-bottom: var(--space-5);
    border-bottom: 1px solid var(--line);
  }
  :root[data-theme="theme"] .timeline-period__header > span { color: var(--accent-strong); font-weight: 800; }
  :root[data-theme="theme"] .timeline-period__header > p { max-width: 54rem; font-size: var(--fs-lg); }
  :root[data-theme="theme"] .timeline-period__moments { position: relative; }
  :root[data-theme="theme"] .timeline-period__moments::before {
    position: absolute;
    top: 0.8rem;
    bottom: 0.8rem;
    left: calc(10.5rem + var(--space-5));
    width: 2px;
    background: var(--accent);
    content: "";
  }
  :root[data-theme="theme"] .timeline-moment { position: relative; }
  :root[data-theme="theme"] .timeline-moment::before {
    position: absolute;
    z-index: 1;
    top: 1.45rem;
    left: calc(10.5rem + var(--space-5) + 1px);
    transform: translateX(-50%);
    width: 0.9rem;
    height: 0.9rem;
    border: 3px solid var(--surface);
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 0 1px var(--accent);
    content: "";
  }
  :root[data-theme="theme"] .timeline-moment__body {
    display: grid;
    grid-template-columns: 10.5rem minmax(0, 1fr);
    gap: calc(var(--space-5) * 2);
    align-items: start;
  }
  :root[data-theme="theme"] .timeline-moment__date {
    padding-top: var(--space-4);
    color: var(--text);
    font-size: var(--fs-sm);
    font-weight: 800;
  }
  :root[data-theme="theme"] .timeline-moment__cards { display: grid; gap: var(--space-3); }
  :root[data-theme="theme"] .timeline-card {
    display: grid;
    gap: var(--space-2);
    min-height: 5.5rem;
    padding: var(--space-5);
    border: 1px solid var(--line);
    border-radius: var(--radius-small);
    background: var(--surface);
  }
  :root[data-theme="theme"] .timeline-card__body,
  :root[data-theme="theme"] .timeline-content { display: grid; gap: var(--space-2); }
  :root[data-theme="theme"] .timeline-content__list { display: grid; gap: var(--space-1); padding-left: var(--space-5); }

  :root[data-theme="theme"] .timeline-nav__toggle {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-4);
    width: 100%;
    min-height: 3.5rem;
    padding: var(--space-3) var(--space-4);
    border: 1px solid var(--line-strong);
    border-radius: var(--radius-small);
    background: var(--surface);
    text-align: left;
    cursor: pointer;
  }
  :root[data-theme="theme"] .timeline-nav__toggle:hover { border-color: var(--accent); }
  :root[data-theme="theme"] .timeline-nav__toggle-copy { display: grid; gap: var(--space-1); }
  :root[data-theme="theme"] .timeline-nav__toggle-action { color: var(--accent-strong); font-size: var(--fs-sm); font-weight: 750; }
  :root[data-theme="theme"] .timeline-nav__row--sheet { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-2); }
  :root[data-theme="theme"] .timeline-nav__row--sheet .timeline-nav__button {
    padding: var(--space-2) var(--space-3);
    border: 1px solid var(--line);
    border-radius: var(--radius-small);
    background: var(--surface);
    text-align: left;
  }
  :root[data-theme="theme"] .timeline-nav__row--sheet .timeline-nav__button:hover,
  :root[data-theme="theme"] .timeline-nav__row--sheet .timeline-nav__button.is-active {
    border-color: var(--accent);
    background: var(--accent-soft);
    color: var(--accent-strong);
  }

  @media (max-width: 759px), (max-height: 759px) {
    :root[data-theme="theme"] .timeline-shell { display: block; }
    :root[data-theme="theme"] .timeline-sidebar { display: none; }
    :root[data-theme="theme"] .timeline-nav-compact {
      position: sticky;
      z-index: 20;
      top: 0;
      display: grid;
      gap: var(--space-3);
      padding: var(--space-3) var(--space-4);
      border-bottom: 1px solid var(--line);
      background: var(--surface);
    }
    :root[data-theme="theme"] .timeline-mobile-title { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); }
    :root[data-theme="theme"] .timeline-mobile-title a { color: var(--accent-strong); font-size: var(--fs-sm); font-weight: 750; text-decoration: none; }
    :root[data-theme="theme"] .timeline-workspace { padding: var(--space-6) var(--space-4); }
    :root[data-theme="theme"] .timeline-period { scroll-margin-top: 9rem; }
  }

  @media (max-width: 620px) {
    :root[data-theme="theme"] .timeline-period__header > p { font-size: var(--fs-md); }
    :root[data-theme="theme"] .timeline-period__moments { gap: var(--space-4); padding-left: var(--space-6); }
    :root[data-theme="theme"] .timeline-period__moments::before { left: 0.4rem; }
    :root[data-theme="theme"] .timeline-moment::before { top: 0.35rem; left: calc(-1.6rem + 1px); }
    :root[data-theme="theme"] .timeline-moment__body { grid-template-columns: 1fr; gap: var(--space-2); }
    :root[data-theme="theme"] .timeline-moment__date { min-height: 1.5rem; padding-top: 0; color: var(--accent-strong); }
    :root[data-theme="theme"] .timeline-card { padding: var(--space-4); }
    :root[data-theme="theme"] .timeline-nav__row--sheet { grid-template-columns: 1fr; }
  }
}