/* Phase-space / chalkboard theme — math, Lisp, Emacs, physics, ML */
@import url("https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500&family=Source+Serif+4:ital,opsz,wght@0,8..60,400;0,8..60,600;1,8..60,400&display=swap");

:root {
  color-scheme: light;
  --bg: #f4f0e6;
  --bg-grid: #e8e2d4;
  --ink: #1a2332;
  --muted: #5c6570;
  --accent: #c45c26;
  --accent-2: #2a6f6f;
  --surface: #ebe4d4;
  --border: #c9c0ae;
  --code-bg: #1e2430;
  --code-fg: #e6e2d8;
  --ok: #2a6f6f;
  --error: #a33;
  --font-display: "Source Serif 4", "Iowan Old Style", Palatino, "Palatino Linotype", serif;
  --font-body: "Source Serif 4", Georgia, serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, monospace;
  --measure: 72ch;
  --max: 54rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #12161c;
    --bg-grid: #1a2029;
    --ink: #e8e2d4;
    --muted: #9aa3ad;
    --accent: #e07a3a;
    --accent-2: #5cb8b8;
    --surface: #1a2029;
    --border: #2e3744;
    --code-bg: #0d1015;
    --code-fg: #e6e2d8;
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 18px;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background-color: var(--bg);
  background-image:
    linear-gradient(var(--bg-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--bg-grid) 1px, transparent 1px);
  background-size: 24px 24px;
  background-attachment: fixed;
  font-family: var(--font-body);
  line-height: 1.65;
}

.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg) 92%, transparent);
  backdrop-filter: blur(6px);
  position: sticky;
  top: 0;
  z-index: 10;
}

.brand {
  display: inline-flex;
  align-items: baseline;
  gap: 0.35rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
}

.brand-lambda,
.brand-name {
  color: var(--ink);
  text-decoration: none;
}

.brand-lambda {
  color: var(--accent);
  font-family: var(--font-mono);
  font-weight: 500;
}

.brand-name:hover {
  color: var(--accent);
}

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

nav a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

nav a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

nav .nav-logout {
  display: inline;
  margin: 0;
}

nav .nav-logout button {
  padding: 0;
  border: none;
  background: transparent;
  color: var(--accent);
  font: inherit;
  cursor: pointer;
}

nav .nav-logout button:hover {
  background: transparent;
  color: var(--accent);
  border-bottom: 1px solid var(--accent);
}

.site-main {
  max-width: var(--max);
  margin: 0 auto;
  padding: 2.5rem 1rem 4rem;
}

.site-footer {
  text-align: center;
  padding: 2rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--muted);
  border-top: 1px solid var(--border);
}

.site-footer .paren {
  color: var(--accent-2);
}

.site-footer a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.site-footer a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

h1,
h2,
h3,
h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 2rem;
  margin: 0 0 0.75rem;
}

.lede,
.tagline {
  color: var(--muted);
  font-size: 1.15rem;
  margin: 0 0 1rem;
  max-width: var(--measure);
}

.intro {
  max-width: var(--measure);
  margin: 0 0 2rem;
  font-size: 1.02rem;
}

.home-section-title {
  font-size: 1.25rem;
  margin: 2rem 0 0.75rem;
  font-family: var(--font-mono);
  font-weight: 500;
  letter-spacing: 0;
  color: var(--muted);
}

.post-list,
.tag-list,
.project-list {
  list-style: none;
  padding: 0;
  margin: 1.5rem 0;
}

.post-list li,
.tag-list li,
.project-list li {
  padding: 0.55rem 0;
  border-bottom: 1px dashed var(--border);
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}

.post-list a,
.tag-list a,
.project-list a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s ease, color 0.25s ease;
}

.post-list a:hover,
.tag-list a:hover,
.project-list a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

time,
.count {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--muted);
}

.note .meta {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--muted);
  margin-bottom: 1.5rem;
}

.note .tags a {
  color: var(--accent-2);
  text-decoration: none;
  margin-right: 0.5rem;
}

.note .content {
  max-width: var(--measure);
}

.note .content p {
  margin: 0 0 1rem;
}

.note--with-toc {
  max-width: min(68rem, 100%);
}

.toc {
  font-size: 0.88rem;
  user-select: none;
}

.toc--sidebar {
  margin: 1.5rem 0 2rem;
  padding: 1rem 1.15rem;
  background: var(--surface);
  border: 1px solid var(--border);
}

.toc-title {
  margin: 0 0 0.65rem;
  font-size: 0.72rem;
  font-weight: 650;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  font-family: var(--font-mono);
}

.toc nav {
  margin: 0;
}

.toc ul {
  margin: 0;
  padding-left: 1.2rem;
}

.toc ul ul {
  padding-left: 1rem;
}

.toc li {
  margin: 0.3rem 0;
}

.toc a {
  color: var(--muted);
  text-decoration: none;
}

.toc a:hover {
  color: var(--accent);
}

@media (min-width: 900px) {
  .note--with-toc {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 15rem;
    column-gap: 2rem;
    max-width: min(68rem, 100%);
  }

  .note--with-toc > header {
    grid-column: 1 / -1;
  }

  .note--with-toc .toc--sidebar {
    grid-column: 2;
    grid-row: 2;
    position: sticky;
    top: 5.5rem;
    align-self: start;
    width: 100%;
    max-height: calc(100vh - 7rem);
    overflow-y: auto;
    margin: 0;
    padding: 1rem 0 1rem 1.25rem;
    background: transparent;
    border: none;
    border-left: 1px solid var(--border);
  }

  .note--with-toc .content {
    grid-column: 1;
    grid-row: 2;
    max-width: none;
    /* Allow the column to shrink; otherwise wide images overflow into the TOC. */
    min-width: 0;
    overflow-x: clip;
  }

  .note--with-toc .backlinks {
    grid-column: 1 / -1;
  }
}

.math-block {
  overflow-x: auto;
  margin: 1.25rem 0;
  font-size: 1.05em;
}

pre.code {
  background: var(--code-bg);
  color: var(--code-fg);
  padding: 1rem 1.1rem;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.5;
  border: 1px solid var(--border);
  margin: 1.25rem 0;
  white-space: pre;
}

pre.code code {
  font-family: inherit;
  font-size: inherit;
  background: none;
  padding: 0;
  border: none;
  white-space: inherit;
}

pre.code span {
  border: none;
  background: none;
  padding: 0;
  margin: 0;
  display: inline;
}

.note .content figure {
  margin: 1.5rem 0;
  max-width: 100%;
  width: 100%;
  overflow: hidden;
}

.note .content figure img,
.note .content img {
  display: block;
  max-width: 100%;
  width: auto;
  height: auto;
  object-fit: contain;
}

.callout,
aside.definition {
  background: var(--surface);
  border-left: 3px solid var(--accent);
  padding: 0.85rem 1rem;
  margin: 1.25rem 0;
}

aside.definition {
  border-left-color: var(--accent-2);
}

.backlinks {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.graph-wrap {
  margin-top: 1.25rem;
}

/* Full-viewport graph page (org-roam style). */
.site-main:has(.graph-wrap--full) {
  max-width: none;
  margin: 0;
  padding: 0;
}

body:has(.graph-wrap--full) {
  overflow: hidden;
}

body:has(.graph-wrap--full) .site-footer {
  display: none;
}

.graph-wrap--full {
  position: relative;
  margin: 0;
}

.graph-wrap--full .graph-root {
  height: calc(100dvh - 4.5rem);
  border: none;
}

.graph-hud {
  position: absolute;
  top: 0.85rem;
  left: 1rem;
  right: 1rem;
  transition: right 0.2s ease;
}

/* Keep the toolbar clear of the preview panel when it's open. */
.graph-wrap--full.has-panel .graph-hud {
  right: calc(min(24rem, 92vw) + 1rem);
}

.graph-hud {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  z-index: 7;
  pointer-events: none;
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

.graph-hud-left {
  position: relative;
  pointer-events: auto;
  flex: 0 1 20rem;
}

.graph-hud-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  pointer-events: auto;
}

#graph-search {
  width: 100%;
  padding: 0.45rem 0.7rem;
  font: inherit;
  color: var(--ink);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  border: 1px solid var(--border);
  backdrop-filter: blur(6px);
}

#graph-search:focus {
  outline: none;
  border-color: var(--accent);
}

.graph-search-results {
  position: absolute;
  top: calc(100% + 0.25rem);
  left: 0;
  right: 0;
  max-height: 50vh;
  overflow-y: auto;
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: 0 8px 24px color-mix(in srgb, var(--ink) 18%, transparent);
}

.graph-search-results button {
  display: block;
  width: 100%;
  padding: 0.5rem 0.7rem;
  font: inherit;
  text-align: left;
  color: var(--ink);
  background: transparent;
  border: none;
  border-bottom: 1px solid color-mix(in srgb, var(--border) 50%, transparent);
  cursor: pointer;
}

.graph-search-results button:hover,
.graph-search-results button:focus {
  background: color-mix(in srgb, var(--accent) 12%, var(--surface));
  outline: none;
}

.graph-panel {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: min(24rem, 92vw);
  padding: 1.1rem 1.25rem 1.5rem;
  overflow-y: auto;
  z-index: 6;
  background: color-mix(in srgb, var(--surface) 94%, transparent);
  border-left: 1px solid var(--border);
  backdrop-filter: blur(8px);
}

.graph-panel h2 {
  margin: 0.2rem 1.5rem 0.35rem 0;
  font-size: 1.25rem;
  line-height: 1.3;
}

.graph-panel h2 a {
  color: var(--ink);
  text-decoration: none;
}

.graph-panel h2 a:hover {
  color: var(--accent);
}

.graph-panel-meta {
  margin: 0 0 0.85rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--muted);
}

.graph-panel-close {
  position: absolute;
  top: 0.65rem;
  right: 0.75rem;
  padding: 0.1rem 0.45rem;
  font: inherit;
  font-size: 1.05rem;
  line-height: 1;
  color: var(--muted);
  background: transparent;
  border: 1px solid transparent;
  cursor: pointer;
}

.graph-panel-close:hover {
  color: var(--accent);
  border-color: var(--border);
}

.graph-panel-excerpt {
  font-size: 0.88rem;
  color: color-mix(in srgb, var(--ink) 88%, transparent);
}

.graph-panel-excerpt > * {
  margin: 0 0 0.6rem;
}

.graph-panel h3 {
  margin: 1.1rem 0 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.graph-panel ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.graph-panel ul button {
  display: block;
  width: 100%;
  padding: 0.28rem 0;
  font: inherit;
  font-size: 0.86rem;
  text-align: left;
  color: var(--accent-2);
  background: transparent;
  border: none;
  cursor: pointer;
}

.graph-panel ul button:hover {
  color: var(--accent);
  text-decoration: underline;
}

.graph-panel-open {
  display: inline-block;
  margin-top: 1.1rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent);
}

.graph-wrap--full .graph-status {
  position: absolute;
  left: 1rem;
  bottom: 0.75rem;
  z-index: 7;
  margin: 0;
  pointer-events: none;
}

.graph-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1rem;
  margin-bottom: 0.65rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--muted);
}

.graph-toolbar[hidden] {
  display: none;
}

.graph-tool-btn {
  padding: 0.35rem 0.75rem;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--ink);
}

.graph-tool-btn.is-active,
.graph-tool-btn[aria-pressed="true"] {
  border-color: var(--accent);
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 12%, var(--surface));
}

.graph-hint {
  color: var(--muted);
}

.graph-status {
  min-height: 1.25rem;
  margin: 0.55rem 0 0;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-2);
}

.graph-root {
  height: min(72vh, 680px);
  background:
    radial-gradient(ellipse at 30% 20%, color-mix(in srgb, var(--accent) 8%, transparent), transparent 55%),
    radial-gradient(ellipse at 80% 70%, color-mix(in srgb, var(--accent-2) 10%, transparent), transparent 50%),
    var(--surface);
  border: 1px solid var(--border);
  opacity: 0;
  animation: graph-in 0.6s ease forwards;
  position: relative;
  overflow: hidden;
  touch-action: none;
}

.graph-root canvas {
  transition: opacity 0.2s ease;
}

.graph-root--link {
  outline: 1px dashed var(--accent);
  outline-offset: -1px;
  cursor: crosshair;
}

.graph-root--admin {
  cursor: grab;
}

@keyframes graph-in {
  to {
    opacity: 1;
  }
}

.auth-form {
  display: grid;
  gap: 0.85rem;
  max-width: 22rem;
}

.auth-form label {
  display: grid;
  gap: 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

.auth-form input,
.auth-form select,
.auth-form textarea,
.edit-note input,
.edit-note select,
.edit-note textarea {
  font: inherit;
  padding: 0.45rem 0.55rem;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--ink);
}

button {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  padding: 0.45rem 0.85rem;
  border: 1px solid var(--accent);
  background: transparent;
  color: var(--accent);
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease;
}

button:hover {
  background: var(--accent);
  color: var(--bg);
}

.table-wrap {
  margin: 1.5rem 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border: 1px solid var(--border);
  background: var(--surface);
  max-width: 100%;
}

.org-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  line-height: 1.45;
}

.org-table thead th {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--accent-2);
  background: color-mix(in srgb, var(--surface) 70%, var(--bg));
  border-bottom: 2px solid var(--border);
  padding: 0.65rem 0.85rem;
  text-align: left;
  white-space: nowrap;
  vertical-align: bottom;
}

.org-table tbody td {
  padding: 0.7rem 0.85rem;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
  color: var(--ink);
}

.org-table tbody tr:last-child td {
  border-bottom: none;
}

.org-table tbody tr:nth-child(even) td {
  background: color-mix(in srgb, var(--bg) 55%, transparent);
}

.org-table tbody tr:hover td {
  background: color-mix(in srgb, var(--accent) 8%, var(--surface));
}

.content .org-table .math-inline,
.content .org-table .katex {
  font-size: 0.95em;
}

.data {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.data th,
.data td {
  text-align: left;
  padding: 0.45rem 0.5rem;
  border-bottom: 1px solid var(--border);
}

.edit-note {
  margin: 0.75rem 0;
  padding: 0.75rem;
  background: var(--surface);
  border: 1px solid var(--border);
}

.edit-note form {
  display: grid;
  gap: 0.5rem;
  margin-top: 0.75rem;
}

.ok {
  color: var(--ok);
}

.error {
  color: var(--error);
}

.badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 0.1rem 0.4rem;
  border: 1px solid var(--border);
  color: var(--muted);
}

.badge-draft {
  color: var(--accent-2);
  border-color: var(--accent-2);
}

.badge-private {
  color: var(--accent);
  border-color: var(--accent);
}

.project-list li[data-status="private"] a {
  color: var(--muted);
}

.drafts-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  margin: 0 0 1.25rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--muted);
  cursor: pointer;
  user-select: none;
}

.drafts-toggle[hidden] {
  display: none;
}

.drafts-toggle input {
  accent-color: var(--accent);
}

.post-list li[data-status="draft"] a {
  color: var(--accent-2);
}

.post-list li[data-status="private"] {
  /* outline paints over the row without shifting layout */
  outline: 1px solid var(--accent);
  outline-offset: 3px;
}

/* syntect classed tokens (SpacedPrefixed with syn-) */
.syn-keyword,
.syn-storage,
.syn-storage.syn-type {
  color: #7aa2f7;
}
.syn-string {
  color: #7ec699;
}
.syn-comment {
  color: #6b7280;
}
.syn-entity.syn-name.syn-function,
.syn-support.syn-function {
  color: #7dcfff;
}
.syn-constant.syn-numeric,
.syn-constant {
  color: #e0af68;
}
.syn-keyword.syn-operator {
  color: #d4a017;
}
.syn-punctuation {
  color: #9aa3ad;
}

/* ---------- Collapsible Org-mode Headings ---------- */
.org-heading {
  cursor: pointer;
  position: relative;
  transition: color 0.15s ease;
}

.org-heading:hover {
  color: var(--accent);
}

.org-heading::before {
  content: "▼";
  display: inline-block;
  margin-right: 0.5rem;
  font-size: 0.7em;
  color: var(--muted);
  transition: transform 0.15s ease, color 0.15s ease;
  vertical-align: middle;
  position: relative;
  top: -1px;
  user-select: none;
}

.org-heading:hover::before {
  color: var(--accent);
}

.org-section.collapsed > .org-heading::before {
  transform: rotate(-90deg);
}

.org-heading::after {
  content: "...";
  display: inline-block;
  margin-left: 0.6rem;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.15s ease, visibility 0.15s ease;
  font-family: var(--font-mono);
  font-size: 0.8em;
  font-weight: normal;
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 18%, transparent);
  padding: 0 0.35rem;
  border-radius: 4px;
  user-select: none;
}

.org-section.collapsed > .org-heading::after {
  opacity: 1;
  visibility: visible;
}

.org-section.collapsed > .org-section-content {
  display: none !important;
}

.org-section .org-section {
  margin-left: 1rem;
  border-left: 1px dashed var(--border);
  padding-left: 0.8rem;
}

.org-section .org-section > .org-heading {
  margin-top: 1.5em;
}

@media (max-width: 640px) {
  .org-section .org-section {
    margin-left: 0.4rem;
    padding-left: 0.4rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .org-heading,
  .org-heading::before,
  .org-heading::after {
    transition: none !important;
  }
}