/*
 * pi-theme: a pass over new-styles.css borrowing the typography and post
 * treatment of pi.website (Physical Intelligence), mixed with this site's own
 * palette and details.
 *
 * From pi.website: monospace UI text at 14px/20px, a serif display face for the
 * name and post titles, muted #686868 secondary text, and index rows drawn as
 * 1px boxes on a left rail with a small square bullet, tinting on hover.
 * Kept from this site: the warm #fffff8 background, the blue links, the red
 * highlight, the margin annotations, and the sans-serif body for long posts
 * (monospace is hard work over a page of prose and math).
 *
 * Loaded after new-styles.css in BaseLayout.astro — remove that one <link> to
 * go back to the original look.
 */

:root {
  --pi-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono",
    "Courier New", monospace;
  --pi-serif: "Newsreader", "Iowan Old Style", Georgia, "Times New Roman", serif;
  --pi-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --pi-muted: #686868; /* pi.website secondary text */
  --pi-rule: #000000; /* pi boxes: 1px solid black */
  --pi-surface: #ffffff; /* pi boxes: white on the page colour */
  --pi-hover: #f1f0e6; /* pi row hover tint */
  --pi-bullet: #111827; /* pi bullet: gray-900 */
  --pi-shadow: 3px 3px 0px #000; /* pi boxed row */
  --pi-shadow-hover: 5px 5px 0px #000;

  /* pi.website page colours, overriding new-styles.css tokens */
  --bg-color: #f5f4ef;
  --text-color: #000000;
  --text-secondary: #000000;
  --text-tertiary: #1a1a1a;
  --text-muted: #686868;
  --text-dim: #686868;
  --border-color: rgba(0, 0, 0, 0.12);
  --border-subtle: rgba(0, 0, 0, 0.18);
  --link-border: rgba(0, 0, 0, 0.45);
}

/* pi links: black, underlined (the red highlight spans stay as they are) */
header a,
main a:not(.project-title):not(.post-title),
footer a,
.blog-post a {
  color: #000;
  text-decoration: underline;
  text-underline-offset: 2px;
  border-bottom: none;
}

.site-sidebar a {
  color: #000;
  text-decoration: none;
}

.site-sidebar a:hover {
  text-decoration: underline;
}

/* ---- Typography ---- */
body {
  font-family: var(--pi-mono);
  font-size: 14px;
  line-height: 20px;
}

/*
 * Article prose, matching pi.website's research pages: they are not monospace —
 * Source Sans 3 at 18px/29.25px in a 768px column, with serif headings.
 */
.blog-post {
  font-family: "Source Sans 3", var(--pi-sans);
  font-size: 18px;
  line-height: 1.625;
}

/*
 * pi keeps the whole page in one narrow left column (768px of text), rather than
 * a wide shell with a narrow article inside it. Match that on blog pages: 832px
 * box = 768px of text inside main's 2rem padding. Two classes + an element beats
 * new-styles.css's `body.blog-wide header, …` and BlogPost.astro's scoped rule.
 */
body.blog-wide.with-sidebar header,
body.blog-wide.with-sidebar main,
body.blog-wide.with-sidebar footer {
  max-width: 832px;
}

body.blog-wide main article.blog-post {
  max-width: none;
  margin-left: 0;
}

/* pi article headings: serif, regular weight */
.blog-post h1 { font-size: 2rem; line-height: 1.25; }
.blog-post h2 { font-size: 1.5rem; line-height: 1.25; }
.blog-post h3 { font-size: 1.25rem; line-height: 1.3; }
.blog-post h1,
.blog-post h2,
.blog-post h3,
.blog-post h4 {
  font-weight: 400;
}

/* post title: pi sets its article h1 much larger than the wordmark */
body.blog-wide header h1 {
  font-size: 2.6rem;
  line-height: 1.15;
}

header h1 {
  font-family: var(--pi-serif);
  font-weight: 400;
  font-size: 1.9rem;
  letter-spacing: 0;
  line-height: 1.2;
}

.blog-post h1,
.blog-post h2,
.blog-post h3,
.blog-post h4 {
  font-family: var(--pi-serif);
  letter-spacing: 0;
}

/* Section headings: mono, quiet, like pi's small labels */
main > section > h3,
.sidebar-title {
  font-family: var(--pi-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.last-updated,
.post-meta,
.post-date,
.post-updated,
.project-year,
footer p,
.annotation-text,
.sidebar-note,
.sidebar-link-date {
  font-family: var(--pi-mono);
  color: var(--pi-muted);
}

/* ---- Index rows (blog list) — pi's boxed row on a bullet rail ---- */
#blog-list .post-list {
  margin-left: 0; /* pi puts the offset on each row (ml-6), not the list */
}

#blog-list .post-item {
  position: relative;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px 6px; /* pi boxed rows: gap-2, inner row gap-1.5 */
  align-items: baseline;
  margin-left: 24px; /* ml-6 */
  margin-bottom: 0.5rem;
  padding: 8px 12px;
  background: var(--pi-surface);
  border: 1px solid var(--pi-rule);
  box-shadow: var(--pi-shadow);
  transition: box-shadow 0.15s ease, background-color 0.15s ease;
}

#blog-list .post-item:hover {
  box-shadow: var(--pi-shadow-hover);
}

/* 7px square bullet on the rail, as on pi.website */
#blog-list .post-item::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 7px; /* pi: top-[7px] */
  width: 7px;
  height: 7px;
  border-radius: 2px;
  background: var(--pi-bullet);
  outline: 2px solid var(--bg-color);
}

/* pi: text-xs truncate font-semibold leading-5 */
#blog-list .post-item .post-title {
  grid-column: 1;
  grid-row: 1;
  min-width: 0;
  font-family: var(--pi-mono);
  font-size: 12px;
  font-weight: 600;
  line-height: 20px;
  color: var(--text-color);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* pi: text-xs text-muted-foreground shrink-0 ml-1 */
#blog-list .post-item .post-date {
  grid-column: 2;
  grid-row: 1;
  margin-left: 4px;
  font-size: 12px;
  line-height: 20px;
  color: var(--pi-muted);
  white-space: nowrap;
}

#blog-list .post-item .post-description {
  grid-column: 1 / -1;
  grid-row: 2;
  font-family: var(--pi-mono);
  font-size: 12px;
  line-height: 16px;
  color: var(--pi-muted);
}

/* ---- Projects — same row treatment, keeping the media thumbnails ---- */
.project-filters {
  font-family: var(--pi-mono);
}

.project-filter {
  font-family: var(--pi-mono);
  font-size: 12px;
}

#projects .project-item,
#projects .project-item-wrapper .project-item {
  position: relative;
  margin-left: 24px;
  margin-bottom: 0.75rem;
  padding: 10px 12px;
  /*
   * pi.website's three tiers:
   *   plain    no box, tints on hover            -> work outside "selected"
   *   soft     hairline box, soft shadow on hover -> selected work        (.is-selected)
   *   strong   black box, hard offset shadow      -> the flagship project (.is-featured)
   * The transparent border keeps all three the same size.
   */
  background: transparent;
  border: 1px solid transparent;
  transition: box-shadow 0.15s cubic-bezier(0.4, 0, 0.2, 1), background-color 0.15s cubic-bezier(0.4, 0, 0.2, 1),
    border-color 0.15s cubic-bezier(0.4, 0, 0.2, 1);
}

#projects .project-item:hover {
  background: var(--pi-hover); /* pi: hover:bg-background-hover */
}

/* soft box */
#projects .project-item.is-selected {
  background: rgba(255, 255, 255, 0.6);
  border-color: #d4d3cb;
}

#projects .project-item.is-selected:hover {
  background: #ffffff;
  border-color: #c0bdad;
  box-shadow: 3px 3px 0px #c0bdad;
}

/* strong box */
#projects .project-item.is-featured {
  background: var(--pi-surface);
  border-color: var(--pi-rule);
  box-shadow: var(--pi-shadow);
}

#projects .project-item.is-featured:hover {
  background: var(--pi-surface);
  border-color: var(--pi-rule);
  box-shadow: var(--pi-shadow-hover);
}

#projects .project-item::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 16px;
  width: 7px;
  height: 7px;
  border-radius: 2px;
  background: var(--pi-bullet);
  outline: 2px solid var(--bg-color);
}

/* year sits top-right of the box, like pi's dates */
#projects .project-item .project-year {
  position: absolute;
  top: 10px;
  right: 12px;
  margin: 0;
  font-size: 12px;
}

#projects .project-title {
  font-family: var(--pi-mono);
  font-size: 13px;
  font-weight: 600;
}

#projects .project-description {
  font-family: var(--pi-mono);
  font-size: 12px;
  line-height: 17px;
  color: var(--pi-muted);
  padding-right: 4.5rem; /* clear the year */
}

#projects .project-links {
  font-family: var(--pi-mono);
  font-size: 12px;
}

#projects .project-media {
  box-shadow: none;
  border: 1px solid var(--pi-rule);
  background: #fff;
}

/* ---- Sidebar ---- */
.site-sidebar {
  font-family: var(--pi-mono);
  font-size: 12px;
  line-height: 16px;
}

.sidebar-item a {
  font-family: var(--pi-mono);
  padding: 2px 4px;
  margin-left: -4px;
  transition: background-color 0.15s ease;
}

.sidebar-item a:hover {
  background: var(--pi-hover);
}

.sidebar-link-title {
  font-size: 12px;
}

.sidebar-link-date {
  font-size: 11px;
}

.sidebar-note {
  font-size: 11px;
  line-height: 15px;
}

/* ---- Blog post page ---- */
.post-toc,
.toc-title,
.toc-number,
.toc-link {
  font-family: var(--pi-mono);
}

nav.post-toc[aria-label="Table of contents"] {
  background: var(--pi-surface);
  border: 1px solid var(--pi-rule);
  box-shadow: var(--pi-shadow);
  padding: 12px 14px;
}

nav.post-toc[aria-label="Table of contents"] .toc-link {
  color: #000;
  text-decoration: none;
}

nav.post-toc[aria-label="Table of contents"] .toc-link:hover {
  text-decoration: underline;
}

.obsidian-figure figcaption {
  font-family: var(--pi-mono);
  color: var(--pi-muted);
}

/* pi spaces its rows 16px apart */
#blog-list .post-item {
  margin-bottom: 16px;
}

/*
 * The local/global graph panel (src/components/GraphView.astro) is styled by
 * Astro's scoped CSS, so match on the component's data attribute to outrank it
 * and give it the same white box + hard shadow as the post rows.
 */
div.graph-view[data-graph-id] {
  background: var(--pi-surface);
  border: 1px solid var(--pi-rule);
  border-left: 1px solid var(--pi-rule);
  box-shadow: var(--pi-shadow);
  padding: 12px 14px;
}

div.graph-view[data-graph-id] .graph-view-title {
  font-family: var(--pi-mono);
  color: var(--pi-muted);
}

/* filter tabs read like pi's underlined nav */
.project-filter.is-active {
  text-decoration: underline;
  text-underline-offset: 3px;
  border-bottom: none;
}

/*
 * ---- Sidebar post list: pi.website's timeline, component for component ----
 *
 * pi markup (homepage): a flex column with `border-l border-gray-300 py-4
 * space-y-4`, gradient fades top and bottom of the rail, and rows `ml-6 px-3
 * py-2` whose 7px `bg-gray-900 rounded-sm` bullet sits at `-left-[40px]
 * top-[7px]` with a 2px outline in the page colour, centred on the rail.
 * Row variants, all reproduced below:
 *   strong  bg-white, border-black, shadow-[3px_3px_0px_#000] → 5px on hover
 *   soft    bg-white/60, border-[#D4D3CB] → hover border-[#C0BDAD],
 *           shadow-[3px_3px_0px_#C0BDAD], bg-white
 *   plain   no box, hover:bg-background-hover
 * Title is `text-xs truncate font-semibold leading-5`, date `text-xs
 * text-muted-foreground shrink-0 ml-1`, the two on one baseline row.
 */
.site-sidebar nav:has(.sidebar-link-title) {
  padding-left: 8px; /* pi: the list's wrapper is pl-2 */
}

.site-sidebar .sidebar-list:has(.sidebar-link-title) {
  position: relative;
  display: flex;
  flex-direction: column;
  row-gap: 12px; /* pi uses 16px (space-y-4); tighter suits the shorter rows here */
  padding: 14px 0;
  border-left: 1px solid #d1d5db; /* border-gray-300 */
}

/* pi fades the rail out at both ends (before:/after: h-6 w-px gradients) */
.site-sidebar .sidebar-list:has(.sidebar-link-title)::before,
.site-sidebar .sidebar-list:has(.sidebar-link-title)::after {
  content: "";
  position: absolute;
  left: -1px;
  width: 1px;
  height: 24px;
}

.site-sidebar .sidebar-list:has(.sidebar-link-title)::before {
  top: 0;
  background: linear-gradient(to top, transparent, var(--bg-color));
}

.site-sidebar .sidebar-list:has(.sidebar-link-title)::after {
  bottom: 0;
  background: linear-gradient(to bottom, transparent, var(--bg-color));
}

.site-sidebar .sidebar-list:has(.sidebar-link-title) .sidebar-item {
  margin: 0;
}

/*
 * row: pi puts title and date on one line, but its rows are 543px wide and this
 * column is 300px, which left room for about two words. Here the date sits under
 * the title (where pi puts its description line) and the title may wrap to two
 * lines; the rail offset and padding are tightened to win back width.
 */
.site-sidebar .sidebar-item a:has(.sidebar-link-title) {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 2px;
  width: auto; /* new-styles.css sets width:100%, which overflows past the rail offset */
  margin: 0 0 0 18px;
  padding: 7px 10px;
  text-decoration: none;
  transition: box-shadow 0.15s cubic-bezier(0.4, 0, 0.2, 1),
    background-color 0.15s cubic-bezier(0.4, 0, 0.2, 1),
    border-color 0.15s cubic-bezier(0.4, 0, 0.2, 1);
}

/* bullet: 7px square centred on the rail, outlined in the page colour */
.site-sidebar .sidebar-item a:has(.sidebar-link-title)::before {
  content: "";
  position: absolute;
  left: -22px; /* rail is 18px left of the box; centre the 7px square on it */
  top: 12px;
  width: 7px;
  height: 7px;
  border-radius: 2px;
  background: #111827; /* bg-gray-900 */
  outline: 2px solid var(--bg-color);
}

/* soft box — pi's non-flagship posts */
.site-sidebar .sidebar-item a:has(.sidebar-link-title) {
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid #d4d3cb;
}

.site-sidebar .sidebar-item a:has(.sidebar-link-title):hover {
  background: #ffffff;
  border-color: #c0bdad;
  box-shadow: 3px 3px 0px #c0bdad;
  text-decoration: none; /* pi's rows don't underline on hover */
}

/* strong box — pi's flagship rows; used here for the post you're reading */
.site-sidebar .sidebar-item a.active:has(.sidebar-link-title) {
  background: #ffffff;
  border-color: #000000;
  box-shadow: 3px 3px 0px #000;
}

.site-sidebar .sidebar-item a.active:has(.sidebar-link-title):hover {
  background: #ffffff;
  border-color: #000000;
  box-shadow: 5px 5px 0px #000;
}

/* title: pi's text-xs font-semibold, but wrapping to two lines instead of truncating to one */
.site-sidebar .sidebar-link-title {
  flex: none;
  min-width: 0;
  font-size: 12px;
  font-weight: 600;
  line-height: 16px;
  white-space: normal;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* date: text-xs text-muted-foreground, on its own line under the title */
.site-sidebar .sidebar-link-date {
  flex: none;
  margin-left: 0;
  font-size: 11px;
  font-weight: 400; /* the active row bolds its link; the date stays regular */
  line-height: 14px;
  color: var(--pi-muted);
  white-space: nowrap;
}

/* plain variant — pi's research rows; here, "all posts →" */
.site-sidebar .sidebar-item-muted a {
  display: block;
  width: auto;
  margin: 0 0 0 18px;
  padding: 7px 10px;
  transition: background-color 0.15s cubic-bezier(0.4, 0, 0.2, 1);
}

.site-sidebar .sidebar-item-muted a:hover {
  background: var(--pi-hover); /* hover:bg-background-hover */
  text-decoration: none;
}

/* ---- Header nav, as on pi.website: serif wordmark left, nav links right ---- */
.site-nav {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 1.5rem;
}

.site-nav-wordmark {
  font-family: var(--pi-serif);
  font-size: 1.5rem;
  line-height: 1.2;
  color: #000;
  text-decoration: none;
}

.site-nav-links {
  display: flex;
  gap: 16px;
}

.site-nav-links a {
  font-family: var(--pi-mono);
  font-size: 14px;
  color: #000;
  text-decoration: underline;
  text-underline-offset: 2px;
}

.site-nav-links a.active {
  font-weight: 600;
}

/* blog rows: keep the summary to two lines, like pi's descriptions */
#blog-list .post-item .post-description {
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* research questions leading a project description */
.project-questions {
  display: block;
  margin-bottom: 8px;
  color: var(--text-color);
}