/* ─── Tokens ─────────────────────────────────────────────── */
:root {
  --bg: #faf9f5;
  --text: #333333;
  --link: #2185c5;
  --toggle-hover-bg: rgba(0, 0, 0, 0.08);

  --border: #e1e4e8;
  --code-bg: #f8f7f4;
  --blockquote-border: #d0d7de;
  --strong-highlight: rgba(33, 133, 197, 0.1);

  --note-text: #0969da;
  --tip-text: #1a7f37;
  --imp-text: #8250df;
  --warn-text: #9a6700;
  --caut-text: #cf222e;
}

[data-theme="dark"] {
  --bg: #212121;
  --text: #e6edf3;
  --link: #6bb8e8;
  --toggle-hover-bg: rgba(255, 255, 255, 0.1);

  --border: #30363d;
  --code-bg: #3a3a3a;
  --blockquote-border: #3d444d;
  --strong-highlight: rgba(107, 184, 232, 0.28);

  --note-text: #79c0ff;
  --tip-text: #56d364;
  --imp-text: #d2a8ff;
  --warn-text: #e3b341;
  --caut-text: #ff7b72;
}

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

body {
  font-family: "Jost", sans-serif;
  font-optical-sizing: auto;
  font-weight: 400;
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text);
  background-color: var(--bg);
  transition: background-color 0.3s ease, color 0.3s ease;
  margin: 0;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ─── Theme toggle ───────────────────────────────────────── */
.theme-toggle {
  position: fixed;
  top: 1.5rem;
  right: 1.5rem;
  background: transparent;
  border: none;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
  transition: background-color 0.2s ease, color 0.3s ease;
  z-index: 100;
}

.theme-toggle:hover {
  background: var(--toggle-hover-bg);
}

.theme-toggle:focus {
  outline: 2px solid var(--link);
  outline-offset: 2px;
}

.sun-icon,
.moon-icon {
  position: absolute;
  transition: opacity 0.3s ease, transform 0.3s ease;
}

:root .sun-icon,
[data-theme="light"] .sun-icon {
  opacity: 0;
  transform: rotate(-90deg) scale(0.8);
}

:root .moon-icon,
[data-theme="light"] .moon-icon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

[data-theme="dark"] .sun-icon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

[data-theme="dark"] .moon-icon {
  opacity: 0;
  transform: rotate(90deg) scale(0.8);
}

/* ─── Layout ─────────────────────────────────────────────── */
.site-header {
  display: flex;
  justify-content: center;
  padding: 2rem 1.5rem 0;
}

.site-header-inner {
  max-width: 720px;
  width: 100%;
}

.site-title {
  display: inline-block;
  font-size: 2rem;
  font-weight: 700;
  text-decoration: none;
}

.site-header nav {
  margin-top: 0.5rem;
  display: flex;
  gap: 1.5rem;
}

.site-header nav a {
  font-size: 1.1rem;
}

.container {
  display: flex;
  flex: 1;
  align-items: center;
  justify-content: center;
}

.container.home {
  padding: 2rem 1.5rem;
}

.container.home>div {
  max-width: 720px;
  width: 100%;
}

.container.bio {
  align-items: flex-start;
}

.container.page {
  align-items: flex-start;
  padding: 2rem 1.5rem 4rem;
}

/* ─── Links ──────────────────────────────────────────────── */
a {
  color: currentColor;
  font-weight: 600;
  text-decoration-color: var(--link);
  text-decoration-thickness: 0.3ex;
  text-underline-offset: 0.3ex;
  transition: text-decoration-thickness 0.2s ease;
}

a:hover {
  text-decoration-thickness: 0.4ex;
}

/* ─── Headings ───────────────────────────────────────────── */
h1 {
  font-weight: 600;
  font-size: 36px;
  margin-top: 0;
}

h2 {
  font-weight: 500;
  font-size: 28px;
}

.prose h1,
.prose h2 {
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.3em;
}

.prose h2 {
  position: relative;
}

.prose h2 .anchor {
  position: absolute;
  left: -1.1em;
  opacity: 0.5;
}

.prose h2 .anchor::before {
  content: "§";
}

.prose h2 .anchor:hover {
  opacity: 1;
}

/* A heading with no text has no line box, so it collapses to near-zero
   height and the anchor's auto top ends up placed off from where it sits
   in a normal heading. Pin its height/position to match. */
.prose h2:has(> .anchor:only-child) {
  min-height: 1.6em;
}

.prose h2:has(> .anchor:only-child) .anchor {
  top: 0;
}

h3 {
  font-weight: 500;
  font-size: 25px;
}

h4 {
  font-weight: 600;
  font-size: 21px;
}


strong {
  font-weight: inherit;
  background-color: var(--strong-highlight);
  border-radius: 3px;
  padding: 0 3px;
}

/* ─── Prose ──────────────────────────────────────────────── */
.prose {
  max-width: 720px;
  width: 100%;
}

.prose p,
.prose li {
  font-family: "Libertinus Serif", serif;
  font-size: 21px;
}

.prose p {
  margin: 0.75em 0;
}

.prose ul,
.prose ol {
  padding-left: 1.5rem;
}

.prose li {
  margin: 0.35em 0;
}

.prose li.task-list-item {
  list-style: none;
}

.prose hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2rem 0;
}

.prose img {
  max-width: 100%;
  height: auto;
}

.prose code {
  font-family: "Cascadia Code", monospace;
  font-optical-sizing: auto;
  font-size: 0.8em;
  background: var(--code-bg);
  border-radius: 4px;
  padding: 0.15em 0.4em;
}

.code-block {
  position: relative;
}

.prose pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 2.5rem 1.5rem 1.5rem;
  overflow-x: auto;
  font-size: 18px;
  line-height: 1.6;
  tab-size: 4;
}

[data-theme="dark"] .prose pre {
  background: #1e1e1e;
}

.prose pre code {
  display: block;
  background: none;
  padding: 0;
  border-radius: 0;
}

.code-lang {
  position: absolute;
  top: 0.5rem;
  left: 0.5rem;
  font-family: "Cascadia Code", monospace;
  font-size: 0.7rem;
  background: var(--border);
  color: var(--text);
  opacity: 0.7;
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
}

.copy-btn {
  position: absolute;
  top: 0.3rem;
  right: 0.4rem;
  background: transparent;
  border: none;
  cursor: pointer;
  color: var(--link);
  opacity: 0.5;
  padding: 0.25rem;
  border-radius: 4px;
  transition: opacity 0.2s ease;
  line-height: 0;
}

.copy-btn:hover {
  opacity: 1;
}

.prose blockquote {
  margin: 1rem 0;
  padding: 0.5rem 0 0.5rem 1rem;
  border-left: 4px solid var(--blockquote-border);
  color: var(--text);
  opacity: 0.8;
}

.prose blockquote p {
  margin: 0;
}

/* ─── Tables ─────────────────────────────────────────────── */
.prose table {
  border-collapse: collapse;
  margin: 1.25rem 0;
}

.prose thead th {
  background: var(--code-bg);
  font-weight: 600;
  text-align: left;
  padding: 0.6rem 1rem;
  border: 1px solid var(--border);
}

.prose tbody td {
  padding: 0.5rem 1rem;
  border: 1px solid var(--border);
}

.prose tbody tr:nth-child(even) {
  background: var(--code-bg);
}

/* ─── Callouts ───────────────────────────────────────────── */
.callout {
  border-left: 0.25rem solid var(--callout-color);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
  background-color: color-mix(in srgb, var(--callout-color) 8%, var(--bg));
}

.callout-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 700;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--callout-color);
  margin-bottom: 0.6rem;
  font-family: "Jost", sans-serif;
}

.callout-title svg {
  flex-shrink: 0;
}

.callout-body {
  font-size: 0.95em;
  line-height: 1.6;
}

.callout-body>*:first-child {
  margin-top: 0;
}

.callout-body>*:last-child {
  margin-bottom: 0;
}

.callout-note {
  --callout-color: var(--note-text);
}

.callout-tip {
  --callout-color: var(--tip-text);
}

.callout-important {
  --callout-color: var(--imp-text);
}

.callout-warning {
  --callout-color: var(--warn-text);
}

.callout-caution {
  --callout-color: var(--caut-text);
}

/* ─── KaTeX ──────────────────────────────────────────────── */
.katex {
  font-size: 1em;
}

.katex-display {
  overflow-x: auto;
  overflow-y: hidden;
  padding: 0.5rem 0;
}

/* ─── Social links ───────────────────────────────────────── */
.social-links {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
}

.social-links a {
  color: var(--text);
  opacity: 0.5;
  transition: opacity 0.2s ease;
  line-height: 0;
}

.social-links a:hover {
  opacity: 1;
}

/* ─── Note list ──────────────────────────────────────────── */
.note-list {
  margin: 0.5rem 0 0;
}

/* ─── Syntax highlighting (VS Code Light+ / Dark Modern) ────── */
.prose pre code {
  color: var(--text);
}

.hljs-keyword {
  color: #af00db;
}

.hljs-storage {
  color: #0000ff;
}

.hljs-string {
  color: #a31515;
}

.hljs-comment {
  color: #008000;
  font-style: italic;
}

.hljs-constant {
  color: #098658;
}

.hljs-variable {
  color: #001080;
}

.hljs-entity.hljs-function,
.hljs-support.hljs-function,
.hljs-support.hljs-macro {
  color: #795e26;
}

.hljs-entity.hljs-class,
.hljs-support.hljs-type {
  color: #267f99;
}

[data-theme="dark"] .prose pre code {
  color: #d4d4d4;
}

[data-theme="dark"] .hljs-keyword {
  color: #c586c0;
}

[data-theme="dark"] .hljs-storage {
  color: #569cd6;
}

[data-theme="dark"] .hljs-string {
  color: #ce9178;
}

[data-theme="dark"] .hljs-comment {
  color: #6a9955;
}

[data-theme="dark"] .hljs-constant {
  color: #b5cea8;
}

[data-theme="dark"] .hljs-variable {
  color: #9cdcfe;
}

[data-theme="dark"] .hljs-entity.hljs-function,
[data-theme="dark"] .hljs-support.hljs-function,
[data-theme="dark"] .hljs-support.hljs-macro {
  color: #dcdcaa;
}

[data-theme="dark"] .hljs-entity.hljs-class,
[data-theme="dark"] .hljs-support.hljs-type {
  color: #4ec9b0;
}