/*
 * posts.css — listing and single-post pages for /posts and /notes.
 * Pairs with blog-notes.css (prose styles).
 */

/* ── Listing page ──────────────────────────────────────────────────────── */
.post-listing {
  max-width: 70ch;
  margin: 0 auto;
  padding: clamp(3rem, 7vw, 5rem) clamp(1.25rem, 4vw, 2rem) var(--sp-9);
}

.post-listing__head {
  margin-bottom: var(--sp-8);
}

.post-listing__kicker {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--fg-3);
  margin: 0 0 var(--sp-4);
}

.post-listing__title {
  font-family: var(--font-serif);
  font-variation-settings: "opsz" 72;
  font-size: clamp(2.4rem, 6vw, 4rem);
  font-weight: 500;
  letter-spacing: -0.02em;
  line-height: 1;
  margin: 0 0 var(--sp-4);
}

.post-listing__desc {
  font-size: var(--text-lg);
  color: var(--fg-2);
  margin: 0;
  max-width: 60ch;
  line-height: 1.5;
}

.post-listing__empty {
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  padding: var(--sp-7) 0;
}
.post-listing__empty p {
  font-family: var(--font-serif);
  font-size: var(--text-xl);
  color: var(--fg-2);
  margin: 0;
  font-style: italic;
}

.post-listing__list {
  list-style: none;
  padding: 0;
  margin: 0;
}

/* Year heading rows */
.post-listing__year-head {
  margin-top: var(--sp-6);
  padding-top: var(--sp-3);
  border-top: 1px solid var(--rule);
}
.post-listing__year-head:first-child {
  margin-top: 0;
  border-top: none;
  padding-top: 0;
}
.post-listing__year-head h2 {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--fg-3);
  margin: 0 0 var(--sp-2);
}

/* Post row */
.post-row {
  border-bottom: 1px solid var(--rule);
}
.post-row:last-child { border-bottom: none; }

.post-row__link {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: baseline;
  gap: var(--sp-2) var(--sp-5);
  padding: var(--sp-5) 0;
  text-decoration: none;
  color: var(--fg);
  position: relative;
  transition: padding-left 220ms cubic-bezier(0.16, 1, 0.3, 1);
}
.post-row__link:hover,
.post-row__link:focus-visible {
  padding-left: var(--sp-3);
}

/* Hover accent — vertical hairline */
.post-row__link::before {
  content: '';
  position: absolute;
  left: 0;
  top: var(--sp-5);
  bottom: var(--sp-5);
  width: 2px;
  background: var(--accent);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform 220ms cubic-bezier(0.16, 1, 0.3, 1);
}
.post-row__link:hover::before,
.post-row__link:focus-visible::before { transform: scaleY(1); }

.post-row__body {
  min-width: 0;
}

.post-row__title {
  font-family: var(--font-serif);
  font-variation-settings: "opsz" 24;
  font-size: var(--text-xl);
  font-weight: 500;
  line-height: 1.2;
  margin: 0 0 var(--sp-2);
  color: var(--fg);
  transition: color 220ms cubic-bezier(0.16, 1, 0.3, 1);
}
.post-row__link:hover .post-row__title,
.post-row__link:focus-visible .post-row__title { color: var(--accent); }

.post-row__desc {
  font-size: var(--text-sm);
  color: var(--fg-2);
  line-height: 1.55;
  margin: 0 0 var(--sp-2);
  max-width: 60ch;
}

.post-row__tags {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--fg-3);
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
}

.post-row__date {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--fg-3);
  white-space: nowrap;
  padding-top: 6px;
}

/* ── Single post page ──────────────────────────────────────────────────── */
.post-page {
  max-width: 70ch;
  margin: 0 auto;
  padding: clamp(3rem, 7vw, 5rem) clamp(1.25rem, 4vw, 2rem) var(--sp-9);
  position: relative;
}

/* When TOC rail is present, expand the wrap. */
.post-page--has-toc {
  max-width: 88ch;
  display: grid;
  grid-template-columns: minmax(0, 70ch) 200px;
  gap: var(--sp-7);
  align-items: start;
}

@media (max-width: 1024px) {
  .post-page--has-toc { display: block; max-width: 70ch; }
  .post-page__toc { display: none; }
}

/* Hairline at top of page, fixed */
.post-page__hairline {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 1px;
  background: var(--rule);
  z-index: 49;
  pointer-events: none;
}

/* Scroll-driven progress bar */
.post-page__progress {
  position: fixed;
  top: 0; left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  z-index: 50;
  transform-origin: 0 50%;
  pointer-events: none;
}
@supports (animation-timeline: scroll()) {
  .post-page__progress {
    width: 100%;
    transform: scaleX(0);
    animation: post-progress-scale linear;
    animation-timeline: scroll();
  }
  @keyframes post-progress-scale {
    to { transform: scaleX(1); }
  }
}

.post-page__main { min-width: 0; }

.post-page__head {
  margin-bottom: var(--sp-7);
}

.post-page__meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--fg-3);
  margin: 0 0 var(--sp-4);
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
  align-items: baseline;
}
.post-page__meta .sep { color: var(--fg-3); opacity: 0.5; }
.post-page__meta a {
  color: var(--fg-3);
  text-decoration: none;
  transition: color 180ms cubic-bezier(0.16, 1, 0.3, 1);
}
.post-page__meta a:hover,
.post-page__meta a:focus-visible { color: var(--accent); }

.post-page__title {
  font-family: var(--font-serif);
  font-variation-settings: "opsz" 72;
  font-size: clamp(2.4rem, 5vw, 3.55rem);
  font-weight: 500;
  letter-spacing: -0.015em;
  line-height: 1.05;
  margin: 0 0 var(--sp-3);
}

.post-page__lede {
  font-size: var(--text-lg);
  color: var(--fg-2);
  line-height: 1.55;
  margin: 0;
  max-width: 60ch;
}

/* Section glyph on h2 in prose (subtle § in left margin) */
.post-page .prose h2 {
  position: relative;
}
.post-page .prose h2::before {
  content: '§';
  position: absolute;
  left: -1.4em;
  top: 0.05em;
  font-family: var(--font-mono);
  font-size: 0.7em;
  color: var(--fg-3);
  font-weight: 400;
}
@media (max-width: 768px) {
  .post-page .prose h2::before { display: none; }
}

/* Prev / next */
.post-page__prev-next {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-5);
  margin-top: var(--sp-9);
  padding-top: var(--sp-5);
  border-top: 1px solid var(--rule);
}

.post-page__prev-next a {
  display: flex;
  flex-direction: column;
  gap: 4px;
  text-decoration: none;
  color: var(--fg-2);
  transition: color 180ms cubic-bezier(0.16, 1, 0.3, 1);
}
.post-page__prev-next a:hover,
.post-page__prev-next a:focus-visible { color: var(--accent); }

.post-page__prev-next .dir {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--fg-3);
}
.post-page__prev-next .title {
  font-family: var(--font-sans);
  font-size: var(--text-md);
  font-weight: 500;
  color: var(--fg);
}
.post-page__prev-next .right {
  text-align: right;
  margin-left: auto;
}

/* Back link */
.post-page__back {
  margin-top: var(--sp-7);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.post-page__back a {
  color: var(--fg-2);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid var(--rule);
  transition: color 180ms cubic-bezier(0.16, 1, 0.3, 1),
              border-color 180ms cubic-bezier(0.16, 1, 0.3, 1);
}
.post-page__back a::before { content: "← "; }
.post-page__back a:hover,
.post-page__back a:focus-visible {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* On this page rail */
.post-page__toc {
  position: sticky;
  top: var(--sp-5);
  align-self: start;
  max-height: calc(100dvh - var(--sp-7));
  overflow-y: auto;
  padding-top: var(--sp-2);
}

.post-page__toc-label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--fg-3);
  margin: 0 0 var(--sp-3);
}

.post-page__toc ul {
  list-style: none;
  padding: 0;
  margin: 0;
  border-left: 1px solid var(--rule);
}

.post-page__toc li { line-height: 1; }

.post-page__toc a {
  display: block;
  padding: var(--sp-2) var(--sp-3);
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  color: var(--fg-3);
  text-decoration: none;
  border-left: 1px solid transparent;
  margin-left: -1px;
  transition: color 180ms cubic-bezier(0.16, 1, 0.3, 1),
              border-color 180ms cubic-bezier(0.16, 1, 0.3, 1);
}
.post-page__toc a:hover,
.post-page__toc a:focus-visible {
  color: var(--accent);
  border-left-color: var(--accent);
}