/* ---------------------------------------------------------------------------
   yoctoblog — a small, nearly-plaintext stylesheet
   Fonts: IBM Plex Sans / Serif / Mono (loaded from the CDN in each page head)
   --------------------------------------------------------------------------- */

:root {
  --sans: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --serif: "IBM Plex Serif", Georgia, "Times New Roman", serif;
  --mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  --bg: #fdfdfb;
  --fg: #1a1a1a;
  --muted: #6f6f6f;
  --rule: #e4e4df;
  --accent: #0b5fce;

  --measure: 41rem;
  --pad: clamp(1.1rem, 4vw, 1.6rem);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121212;
    --fg: #e7e7e3;
    --muted: #9b9b96;
    --rule: #2c2c2c;
    --accent: #8ab4ff;
  }
}

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

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--serif);
  font-size: clamp(1rem, 0.96rem + 0.2vw, 1.09rem);
  line-height: 1.65;
  overflow-wrap: break-word;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

.wrap {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 2.6rem var(--pad) 5rem;
}

.video-container {
  position: relative;
  padding-bottom: 56.25%; /* 16:9 */
  height: 0;
}
.video-container iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

/* --- links ---------------------------------------------------------------- */

a {
  color: var(--fg);
  text-decoration: underline;
  text-decoration-color: var(--rule);
  text-decoration-thickness: 0.06em;
  text-underline-offset: 0.16em;
}
a:hover { text-decoration-color: currentColor; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 2px;
}

::selection { background: var(--accent); color: #fff; }

/* --- header / footer ------------------------------------------------------ */

.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  padding-bottom: 0.9rem;
  margin-bottom: 2.6rem;
  border-bottom: 1px solid var(--rule);
}

.site-title {
  font-family: var(--sans);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
  text-decoration: none;
}
.site-title:hover { text-decoration: underline; }

.site-nav {
  display: flex;
  gap: 1.15rem;
  font-family: var(--mono);
  font-size: 0.78rem;
}
.site-nav a { color: var(--muted); text-decoration: none; }
.site-nav a:hover,
.site-nav a[aria-current="page"] { color: var(--fg); text-decoration: underline; }

.site-footer {
  margin-top: 4rem;
  padding-top: 1rem;
  border-top: 1px solid var(--rule);
  font-family: var(--mono);
  font-size: 0.74rem;
  color: var(--muted);
}
.site-footer p { margin: 0; }

/* --- typography ----------------------------------------------------------- */

h1, h2, h3, h4 {
  font-family: var(--sans);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.015em;
}
h1 { font-size: 1.6rem; margin: 0 0 1rem; }
h2 { font-size: 1.24rem; margin: 2.3rem 0 0.7rem; }
h3 { font-size: 1.05rem; margin: 1.8rem 0 0.5rem; }
p { margin: 0 0 1.1rem; }
ul, ol { margin: 0 0 1.1rem; padding-left: 1.4rem; }
li { margin: 0.25rem 0; }
hr { border: 0; border-top: 1px solid var(--rule); margin: 2.5rem 0; }
.muted { color: var(--muted); }

blockquote {
  margin: 1.5rem 0;
  padding: 0.1rem 0 0.1rem 1.1rem;
  border-left: 2px solid var(--rule);
  color: var(--muted);
}
blockquote p:last-child { margin-bottom: 0; }

img, svg, video { max-width: 100%; height: auto; }

figure { margin: 1.6rem 0; }
figcaption {
  margin-top: 0.45rem;
  font-family: var(--mono);
  font-size: 0.74rem;
  color: var(--muted);
}

table { width: 100%; border-collapse: collapse; font-size: 0.92rem; }
th, td { text-align: left; padding: 0.4rem 0.6rem; border-bottom: 1px solid var(--rule); }

code, kbd, samp { font-family: var(--mono); font-size: 0.85em; }
code { background: rgba(0, 0, 0, 0.045); padding: 0.08em 0.32em; border-radius: 3px; }
pre {
  font-family: var(--mono);
  font-size: 0.82rem;
  line-height: 1.55;
  background: rgba(0, 0, 0, 0.04);
  border-radius: 4px;
  padding: 0.9rem 1rem;
  margin: 0 0 1.2rem;
  overflow-x: auto;
}
pre code { background: none; padding: 0; font-size: inherit; }

@media (prefers-color-scheme: dark) {
  code { background: rgba(255, 255, 255, 0.08); }
  pre { background: rgba(255, 255, 255, 0.06); }
}

/* --- page title ----------------------------------------------------------- */

.page-title { font-family: var(--sans); }

/* --- post list (front page & tag pages) ----------------------------------- */

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

.post-item {
  display: grid;
  grid-template-columns: 7rem 1fr;
  column-gap: 1.5rem;
  padding: 1.15rem 0;
  border-bottom: 1px solid var(--rule);
}
.post-item:first-child { border-top: 1px solid var(--rule); }

.post-date {
  font-family: var(--mono);
  font-size: 0.76rem;
  color: var(--muted);
  padding-top: 0.25rem;
  white-space: nowrap;
}

.post-title {
  font-family: var(--sans);
  font-weight: 600;
  font-size: 1.06rem;
  text-decoration: none;
}
.post-title:hover { text-decoration: underline; }

.post-summary {
  margin: 0.3rem 0 0;
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.55;
}

.post-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.15rem 0.9rem;
  margin: 0.5rem 0 0;
  font-family: var(--mono);
  font-size: 0.74rem;
}
.post-tags .tag { color: var(--muted); text-decoration: none; }
.post-tags .tag:hover { color: var(--fg); text-decoration: underline; }

@media (max-width: 34rem) {
  .post-item { grid-template-columns: 1fr; row-gap: 0.15rem; }
  .post-date { padding-top: 0; }
}

/* --- tag tree (tags index) ------------------------------------------------ */

.tag-tree {
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--mono);
  font-size: 0.85rem;
}
.tag-tree ul {
  list-style: none;
  margin: 0.15rem 0 0.15rem 0.35rem;
  padding-left: 0.9rem;
  border-left: 1px solid var(--rule);
}
.tag-tree li { padding: 0.16rem 0; }
.tag-tree a { text-decoration: none; }
.tag-tree a:hover { text-decoration: underline; }
.tag-count { color: var(--muted); }

.subtags {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.15rem 0.9rem;
  margin: 0 0 1.6rem;
  font-family: var(--mono);
  font-size: 0.76rem;
}
.subtags .label { color: var(--muted); }
.subtags .tag { color: var(--muted); text-decoration: none; }
.subtags .tag:hover { color: var(--fg); text-decoration: underline; }

/* --- breadcrumb ----------------------------------------------------------- */

.breadcrumb {
  margin: 0 0 0.7rem;
  font-family: var(--mono);
  font-size: 0.76rem;
  color: var(--muted);
}
.breadcrumb a { color: var(--muted); }
.breadcrumb .sep { padding: 0 0.35rem; color: var(--rule); }
.breadcrumb .current { color: var(--fg); }

.tag-count { font-family: var(--mono); font-size: 0.76rem; }

/* --- single post ---------------------------------------------------------- */

.post-header { margin-bottom: 2rem; }
.post-header h1 { margin-bottom: 0.35rem; }
.post-header .post-date { display: block; padding-top: 0; }

.post-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.15rem 1rem;
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 1px solid var(--rule);
}
.post-footer .label {
  font-family: var(--mono);
  font-size: 0.74rem;
  color: var(--muted);
}
.post-footer .post-tags { margin: 0; }

/* --- syntax highlighting (Prism token classes) ---------------------------- */
/* We skip Prism's own theme and colour the tokens to match the site. */

:root {
  --code-comment: #6e7781;
  --code-keyword: #cf222e;
  --code-string: #0a3069;
  --code-number: #0550ae;
  --code-function: #8250df;
  --code-tag: #116329;
}

@media (prefers-color-scheme: dark) {
  :root {
    --code-comment: #8b949e;
    --code-keyword: #ff7b72;
    --code-string: #a5d6ff;
    --code-number: #79c0ff;
    --code-function: #d2a8ff;
    --code-tag: #7ee787;
  }
}

.token.comment,
.token.prolog,
.token.doctype,
.token.cdata { color: var(--code-comment); font-style: italic; }

.token.punctuation { color: var(--muted); }

.token.keyword,
.token.atrule,
.token.rule { color: var(--code-keyword); }

.token.string,
.token.char,
.token.attr-value,
.token.builtin,
.token.inserted,
.token.selector { color: var(--code-string); }

.token.number,
.token.boolean,
.token.constant,
.token.symbol { color: var(--code-number); }

.token.function,
.token.class-name { color: var(--code-function); }

.token.tag,
.token.attr-name,
.token.property,
.token.variable,
.token.regex { color: var(--code-tag); }

.token.operator,
.token.entity,
.token.url { color: var(--fg); }

.token.deleted { color: var(--code-keyword); }
.token.important { font-weight: 600; }
.token.italic { font-style: italic; }