/*
  Gruvbox — canonical color mapping for every semantic element
  Dark:  bg=#282828  fg=#ebdbb2
  Light: bg=#fbf1c7  fg=#3c3836

  Semantic assignments (consistent in both modes):
    H1 / titles → orange (page title, in-body H1, entry titles in lists)
    H2        → aqua   (structure/section; also section labels)
    H3        → green  (subsection)
    H4        → purple (minor heading, italic)
    Links     → blue   (navigation/reference)
    Blockquote→ purple (quoted voice)
    Inline code→ red   (literal/technical)
    Dates/meta → yellow (temporal/context)
    Labels/UI  → gray  (chrome, not content)
    Code block bg → bg_soft surface
*/

/* ─── Fonts ──────────────────────────────────────────────────────────────── */
/*
  Source Serif 4 (SIL Open Font License — static/fonts/OFL.txt), self-hosted.
  Trimmed from ~2 MB to ~80 KB:
    - characters: Latin + accents (incl. pinyin tones, IAST), punctuation, arrows, ₹ €
    - roman: variable weight 400–700; italic: 400 only (bold italic is synthesised)
    - optical size fixed at 20 (text size)
  Anything outside the set (e.g. Devanagari) falls back to the system serif.
*/
@font-face {
  font-family: 'Source Serif 4';
  src: url('fonts/source-serif-4-roman.woff2') format('woff2');
  font-weight: 400 700; font-style: normal; font-display: swap;
  unicode-range: U+0020-007E, U+00A0-017F, U+01CD-01DC, U+02BC, U+02C6, U+02DA, U+02DC, U+1E00-1EFF, U+2000-206F, U+2074, U+20AC, U+20B9, U+2122, U+2190-2199, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: 'Source Serif 4';
  src: url('fonts/source-serif-4-italic.woff2') format('woff2');
  font-weight: 400; font-style: italic; font-display: swap;
  unicode-range: U+0020-007E, U+00A0-017F, U+01CD-01DC, U+02BC, U+02C6, U+02DA, U+02DC, U+1E00-1EFF, U+2000-206F, U+2074, U+20AC, U+20B9, U+2122, U+2190-2199, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* ─── Gruvbox Tokens ─────────────────────────────────────────────────────── */
:root, [data-theme="light"] {
  /* Gruvbox Light surfaces */
  --color-bg:              #fbf1c7;   /* bg */
  --color-surface:         #f2e5bc;   /* bg0_s */
  --color-surface-2:       #ebdbb2;   /* bg1 */
  --color-surface-offset:  #d5c4a1;   /* bg2 */
  --color-surface-dynamic: #bdae93;   /* bg3 */
  --color-divider:         #d5c4a1;   /* bg2 */
  --color-border:          #bdae93;   /* bg3 */

  /* Gruvbox Light text */
  --color-text:            #3c3836;   /* fg1 */
  --color-text-muted:      #665c54;   /* fg3 */
  --color-text-faint:      #928374;   /* gray */
  --color-text-inverse:    #fbf1c7;

  /* ── Semantic accent colors (Gruvbox Light) ── */
  --color-primary:         #076678;   /* blue — links */
  --color-primary-hover:   #458588;
  --color-primary-active:  #689d6a;

  --color-h1:              #af3a03;   /* orange — titles */
  --color-h2:              #427b58;   /* aqua — structure */
  --color-h3:              #79740e;   /* green — subsection */
  --color-h4:              #8f3f71;   /* purple — minor */

  --color-quote:           #8f3f71;   /* purple — blockquote */
  --color-quote-bg:        #f0e4ec;   /* purple tint surface */

  --color-code-inline:     #9d0006;   /* red — literal/technical */
  --color-code-bg:         #f2e5bc;   /* bg0_s */

  --color-meta:            #8f5c0f;   /* yellow, darkened from #b57614 to pass 4.5:1 on bg */
  --color-label:           #928374;   /* gray — UI chrome labels */

  --shadow-sm: 0 1px 3px rgba(60,56,54,0.10);
  --shadow-md: 0 4px 12px rgba(60,56,54,0.12);
}

[data-theme="dark"] {
  /* Gruvbox Dark surfaces */
  --color-bg:              #282828;   /* bg */
  --color-surface:         #32302f;   /* bg0_s */
  --color-surface-2:       #3c3836;   /* bg1 */
  --color-surface-offset:  #504945;   /* bg2 */
  --color-surface-dynamic: #665c54;   /* bg3 */
  --color-divider:         #3c3836;   /* bg1 */
  --color-border:          #504945;   /* bg2 */

  /* Gruvbox Dark text */
  --color-text:            #ebdbb2;   /* fg1 */
  --color-text-muted:      #a89984;   /* fg4 */
  --color-text-faint:      #928374;   /* gray — same in both modes */
  --color-text-inverse:    #282828;

  /* ── Semantic accent colors (Gruvbox Dark) ── */
  --color-primary:         #83a598;   /* blue — links */
  --color-primary-hover:   #8ec07c;
  --color-primary-active:  #b8bb26;

  --color-h1:              #fe8019;   /* orange — titles */
  --color-h2:              #8ec07c;   /* aqua */
  --color-h3:              #b8bb26;   /* green */
  --color-h4:              #d3869b;   /* purple */

  --color-quote:           #d3869b;   /* purple */
  --color-quote-bg:        #3a2d34;   /* purple tint on dark surface */

  --color-code-inline:     #fb4934;   /* red */
  --color-code-bg:         #32302f;   /* bg0_s */

  --color-meta:            #fabd2f;   /* yellow */
  --color-label:           #928374;   /* gray — same in both modes */

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.30);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.40);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --color-bg:              #282828;
    --color-surface:         #32302f;
    --color-surface-2:       #3c3836;
    --color-surface-offset:  #504945;
    --color-surface-dynamic: #665c54;
    --color-divider:         #3c3836;
    --color-border:          #504945;
    --color-text:            #ebdbb2;
    --color-text-muted:      #a89984;
    --color-text-faint:      #928374;
    --color-text-inverse:    #282828;
    --color-primary:         #83a598;
    --color-primary-hover:   #8ec07c;
    --color-primary-active:  #b8bb26;
    --color-h1:              #fe8019;
    --color-h2:              #8ec07c;
    --color-h3:              #b8bb26;
    --color-h4:              #d3869b;
    --color-quote:           #d3869b;
    --color-quote-bg:        #3a2d34;
    --color-code-inline:     #fb4934;
    --color-code-bg:         #32302f;
    --color-meta:            #fabd2f;
    --color-label:           #928374;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.30);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.40);
  }
}

/* ─── Shared tokens ──────────────────────────────────────────────────────── */
:root {
  --font-serif: 'Source Serif 4', Georgia, 'Times New Roman', serif;
  --font-sans:  system-ui, -apple-system, sans-serif;
  --font-mono:  'Consolas', 'Menlo', 'Liberation Mono', monospace;

  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw, 1.125rem);
  --text-lg:   clamp(1.125rem, 1rem    + 0.75vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1.2rem  + 1.25vw, 2.25rem);
  --text-2xl:  clamp(2rem,     1.2rem  + 2.5vw,  3.5rem);

  --space-1: 0.25rem; --space-2: 0.5rem;  --space-3: 0.75rem;
  --space-4: 1rem;    --space-5: 1.25rem; --space-6: 1.5rem;
  --space-8: 2rem;    --space-10: 2.5rem; --space-12: 3rem;
  --space-16: 4rem;   --space-20: 5rem;   --space-24: 6rem;

  --content-width: 680px;
  --transition: 160ms cubic-bezier(0.16, 1, 0.3, 1);
  --radius-sm: 0.25rem;
  --radius-md: 0.375rem;
}

/* ─── Reset ──────────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  scroll-padding-top: var(--space-8);
  hanging-punctuation: first last;
}

body {
  min-height: 100dvh;
  font-family: var(--font-serif);
  font-size: var(--text-base);
  line-height: 1.65;
  color: var(--color-text);
  background-color: var(--color-bg);
  transition: background-color var(--transition), color var(--transition);
}

img, picture, svg { display: block; max-width: 100%; }
ul, ol { list-style: none; }
input, button, select { font: inherit; color: inherit; }
button { cursor: pointer; background: none; border: none; }
h1, h2, h3, h4 { text-wrap: balance; line-height: 1.25; }
p, li { text-wrap: pretty; }

::selection {
  background: color-mix(in srgb, var(--color-meta) 30%, transparent);
  color: var(--color-text);
}

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

a, button {
  transition: color var(--transition), background-color var(--transition),
              opacity var(--transition);
}

/* ─── Layout ─────────────────────────────────────────────────────────────── */
.site-wrapper {
  max-width: var(--content-width);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

/* ─── Header ─────────────────────────────────────────────────────────────── */
.site-header {
  padding-block: var(--space-12) var(--space-8);
  border-bottom: 1px solid var(--color-divider);
}

.header-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  margin-bottom: var(--space-3);
}

.site-identity {
  display: flex; align-items: center;
  gap: var(--space-3); text-decoration: none; color: inherit;
}

.site-mark { flex-shrink: 0; color: var(--color-h2); }

.site-name {
  font-size: var(--text-xl);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-text);         /* site name stays fg — brand, not a heading */
}

.site-tagline {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  font-style: italic;
  margin-bottom: var(--space-5);
}

.theme-toggle {
  width: 32px; height: 32px;
  display: flex; align-items: center; justify-content: center;
  color: var(--color-label);
  border-radius: var(--radius-sm);
  flex-shrink: 0; margin-top: var(--space-1);
}
.theme-toggle:hover { color: var(--color-meta); }

/* ─── Nav ────────────────────────────────────────────────────────────────── */
.site-nav {
  display: flex; flex-wrap: wrap;
  gap: var(--space-1) var(--space-4);
  font-size: var(--text-sm);
}

.site-nav a {
  color: var(--color-text-muted);
  text-decoration: none;
  padding-block: var(--space-1);
}

.site-nav a:hover { color: var(--color-primary); }

.site-nav a[aria-current="page"] {
  color: var(--color-primary);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

/* ─── Main ───────────────────────────────────────────────────────────────── */
main { padding-block: var(--space-10) var(--space-16); }

/* ─── Sections ───────────────────────────────────────────────────────────── */
.section { margin-bottom: var(--space-12); }

.section-header {
  display: flex; align-items: baseline;
  gap: var(--space-4); margin-bottom: var(--space-5);
}

.section-title {
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-h2);           /* aqua — section structure */
  font-family: var(--font-sans);
}

.section-link {
  font-size: var(--text-xs);
  color: var(--color-primary);
  text-decoration: none;
  font-family: var(--font-sans);
}
.section-link:hover { text-decoration: underline; text-decoration-thickness: 1px; }

/* ─── About ──────────────────────────────────────────────────────────────── */
.about-text { font-size: var(--text-base); color: var(--color-text); max-width: 62ch; }
.about-text + .about-text { margin-top: var(--space-4); }

/* ─── Entry list ─────────────────────────────────────────────────────────── */
.entry-list { display: flex; flex-direction: column; gap: var(--space-2); }

.entry-item {
  display: grid;
  grid-template-columns: 7rem 1fr;
  gap: var(--space-4); align-items: baseline;
  padding-block: var(--space-1);
}

.entry-date {
  font-size: var(--text-xs);
  color: var(--color-meta);         /* yellow — temporal context */
  font-family: var(--font-sans);
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
  padding-top: 0.15em;
}

.entry-title a { color: var(--color-h1); font-weight: 500; text-decoration: none; font-size: var(--text-base); }
.entry-title a:hover {
  color: var(--color-primary);
  text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px;
}

.entry-desc {
  grid-column: 2;
  font-size: var(--text-sm); color: var(--color-text-muted);
  margin-top: var(--space-1); max-width: 56ch;
}

/* ─── Item list ──────────────────────────────────────────────────────────── */
.item-list { display: flex; flex-direction: column; gap: var(--space-3); }
.item { display: flex; flex-direction: column; gap: var(--space-1); }

.item-title a { color: var(--color-h1); font-weight: 500; text-decoration: none; font-size: var(--text-base); }
.item-title a:hover {
  color: var(--color-primary);
  text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px;
}

.item-meta {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  font-family: var(--font-sans);
}

/* ─── Links section ──────────────────────────────────────────────────────── */
.link-group { margin-bottom: var(--space-6); }

.link-group-title {
  font-size: var(--text-xs); font-weight: 700;
  letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--color-h3);           /* green — sub-group */
  font-family: var(--font-sans); margin-bottom: var(--space-2);
}

.link-row {
  display: flex; flex-wrap: wrap;
  gap: var(--space-1) var(--space-4);
  font-size: var(--text-base);
}

.link-row a { color: var(--color-primary); text-decoration: none; }
.link-row a:hover {
  text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px;
  color: var(--color-primary-hover);
}

/* ─── Divider ────────────────────────────────────────────────────────────── */
hr { border: none; border-top: 1px solid var(--color-divider); margin-block: var(--space-12); }

/* ─── Footer ─────────────────────────────────────────────────────────────── */
.site-footer {
  border-top: 1px solid var(--color-divider);
  padding-block: var(--space-8);
}
.footer-inner {
  display: flex; flex-wrap: wrap;
  justify-content: space-between; align-items: center; gap: var(--space-4);
}

.footer-links { display: flex; gap: var(--space-5); font-size: var(--text-sm); }
.footer-links a { color: var(--color-text-muted); text-decoration: none; }
.footer-links a:hover { color: var(--color-primary); }

.footer-note {
  font-size: var(--text-xs);
  color: var(--color-label);        /* gray */
  font-family: var(--font-sans);
}

/* ─── Article: header ────────────────────────────────────────────────────── */
.article-header { margin-bottom: var(--space-6); }

.article-title {
  font-size: var(--text-xl); font-weight: 700;
  letter-spacing: -0.02em; line-height: 1.2;
  color: var(--color-h1);
  margin-bottom: var(--space-2);
}

.article-meta {
  font-size: var(--text-sm);
  color: var(--color-meta);         /* yellow — date is temporal context */
  font-family: var(--font-sans);
  margin-top: var(--space-2);
}

/* ─── Article: body ──────────────────────────────────────────────────────── */
.article-body {
  font-size: var(--text-base); color: var(--color-text); max-width: 65ch;
}

.article-body p { margin-bottom: var(--space-4); }
.article-body p:last-child { margin-bottom: 0; }

/* ── Heading hierarchy ── */
.article-body h1 {
  font-size: var(--text-xl); font-weight: 700;
  color: var(--color-h1);
  margin-top: var(--space-10); margin-bottom: var(--space-3);
  padding-bottom: var(--space-2);
  border-bottom: 1px solid var(--color-divider);
}

.article-body h2 {
  font-size: var(--text-lg); font-weight: 700;
  color: var(--color-h2);           /* aqua */
  margin-top: var(--space-8); margin-bottom: var(--space-2);
}

.article-body h3 {
  font-size: var(--text-base); font-weight: 700;
  color: var(--color-h3);           /* orange */
  margin-top: var(--space-6); margin-bottom: var(--space-2);
  letter-spacing: 0.01em;
}

.article-body h4 {
  font-size: var(--text-base); font-weight: 600; font-style: italic;
  color: var(--color-h4);           /* green */
  margin-top: var(--space-5); margin-bottom: var(--space-1);
}

/* ── Links ── */
.article-body a {
  color: var(--color-primary);      /* blue */
  text-decoration: underline;
  text-decoration-thickness: 1px; text-underline-offset: 3px;
}
.article-body a:hover { color: var(--color-primary-hover); }

/* ── Blockquote ── */
.article-body blockquote {
  border-left: 3px solid var(--color-quote);  /* purple */
  background: var(--color-quote-bg);
  color: var(--color-quote);
  padding: var(--space-4) var(--space-6);
  margin-block: var(--space-6);
  font-style: italic;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

/* ── Inline code ── */
.article-body code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  color: var(--color-code-inline);  /* red */
  background: var(--color-code-bg);
  border: 1px solid var(--color-border);
  padding: 0.1em 0.35em;
  border-radius: var(--radius-sm);
}

/* ── Code block ── */
.article-body pre {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-5);
  overflow-x: auto;
  margin-block: var(--space-6);
}
.article-body pre code {
  background: none; border: none; padding: 0;
  font-size: var(--text-sm);
  color: var(--color-text);         /* back to normal fg inside blocks */
}

/* ── Lists ── */
.article-body ul, .article-body ol {
  padding-left: var(--space-5); margin-bottom: var(--space-5);
  list-style: revert;
}
.article-body li { margin-bottom: var(--space-1); }

/* ── Status badge (for reading notes etc.) ── */
.article-body .status {
  display: inline-block;
  font-size: var(--text-xs); font-family: var(--font-sans);
  color: var(--color-meta);         /* yellow */
  border: 1px solid var(--color-meta);
  border-radius: var(--radius-sm);
  padding: 0.1em 0.5em;
  vertical-align: middle;
  margin-left: var(--space-2);
}

/* ─── Back link ──────────────────────────────────────────────────────────── */
.back-link {
  display: inline-flex; align-items: center; gap: var(--space-2);
  font-size: var(--text-sm); color: var(--color-text-muted);
  text-decoration: none; margin-bottom: var(--space-8);
  font-family: var(--font-sans);
}
.back-link:hover { color: var(--color-primary); }

/* ─── RSS links ──────────────────────────────────────────────────────────── */
.rss-link {
  display: inline-flex; align-items: center; gap: 0.3em;
  color: var(--color-primary); text-decoration: none;
  font-family: var(--font-sans);
}
.rss-link:hover { color: var(--color-primary-hover); text-decoration: underline; text-decoration-thickness: 1px; }
.rss-icon { display: inline-block; flex-shrink: 0; }
.section-header .rss-link { margin-left: auto; }
.footer-links .rss-link { color: var(--color-text-muted); }
.footer-links .rss-link:hover { color: var(--color-primary); }
.list-desc { font-size: var(--text-sm); color: var(--color-text-muted); font-style: italic; }

/* ─── Archive ────────────────────────────────────────────────────────────── */
.archive-year { margin-bottom: var(--space-10); }
.archive-year-title { margin-bottom: var(--space-4); }
.entry-title a.archive-section {
  display: inline-block; margin-left: var(--space-2);
  font-family: var(--font-sans); font-size: var(--text-xs);
  color: var(--color-label); text-decoration: none;
  border: 1px solid var(--color-border); border-radius: var(--radius-sm);
  padding: 0 0.4em; vertical-align: 0.15em; font-weight: 400;
}
.entry-title a.archive-section:hover { color: var(--color-primary); border-color: var(--color-primary); }
.article-meta .updated { color: var(--color-text-muted); }

/* ─── Scroll-fade reveal ─────────────────────────────────────────────────── */
@supports (animation-timeline: scroll()) {
  .fade-in {
    opacity: 0;
    animation: reveal-fade linear both;
    animation-timeline: view();
    animation-range: entry 0% entry 60%;
  }
}
@keyframes reveal-fade { from { opacity: 0; } to { opacity: 1; } }

/* ─── Mobile ─────────────────────────────────────────────────────────────── */
@media (max-width: 480px) {
  .entry-item { grid-template-columns: 1fr; gap: var(--space-1); }
  .entry-desc { grid-column: 1; }
  .site-wrapper { padding-inline: var(--space-4); }
}

/* ─── Print ──────────────────────────────────────────────────────────────── */
@media print {
  body { background: #fff; color: #000; }
  .theme-toggle, .site-nav, .back-link { display: none; }
  .article-body a[href]::after { content: " (" attr(href) ")"; font-size: 0.8em; color: #555; }
  .site-footer { page-break-inside: avoid; }
}