/* plssg default CSS - monochrome skeleton; all knobs are CSS variables */
:root {
  /* colors */
  --color-text:        #000;
  --color-bg:          #fff;
  --color-border:      #000;
  --color-hover-bg:    #eee;
  --color-code-bg:     #f5f5f5;
  /* font families */
  --font-family-body:  Helvetica, Verdana, Arial, 'Liberation Sans', FreeSans, sans-serif;
  --font-family-mono:  Menlo, Consolas, 'Liberation Mono', monospace;
  /* font sizes */
  --font-body:    84%;
  --font-nav:     1.5em;
  --font-banner:  1.9em;
  --font-sidebar: 120%;
  --font-h1:      145.5%;
  --font-h2:      115.5%;
  --font-h3:      105%;
  --font-h4:      100%;
  --font-h5:      95%;
  --font-h6:      90%;
  --font-pre:     1.05em;
  --font-code:    0.95em;
  --font-footer:  0.95em;
  /* layout */
  --sidebar-width:      16em;
  --content-max-width:  70em;
}
body {
  color: var(--color-text);
  background-color: var(--color-bg);
  font-family: var(--font-family-body);
  font-size: var(--font-body);
  margin: 0;
  padding: 0;
}
a { text-decoration: none; color: var(--color-text); }
a:hover { text-decoration: underline; }

/* Header */
header { padding: 0; margin: 0; }
header nav {
  background-color: var(--color-bg);
  color: var(--color-text);
  font-size: var(--font-nav);
  min-height: 1.6em;
  padding: 0.25ex 0.4em;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--color-border);
}
header nav a { color: var(--color-text); padding: 0 0.5ex; }
header nav a:hover { background-color: var(--color-hover-bg); text-decoration: none; }
.home-button { font-weight: bold; display: inline-flex; align-items: center; gap: 0.4em; }
/* anchor logo size to root font so logo_size is independent of --font-nav */
.site-logo { font-size: 1rem; vertical-align: middle; }
.top-nav a { margin-left: 0.6em; }
.top-nav a.current {
  background-color: var(--color-text);
  color: var(--color-bg);
  padding: 0 0.4ex;
}

header h1 {
  background-color: var(--color-bg);
  color: var(--color-text);
  font-size: var(--font-banner);
  font-weight: normal;
  margin: 0;
  padding: 0.25ex 0 0.25ex 4mm;
  border: solid 0 var(--color-border);
  border-width: 0 0 1px 0;
}
header h1 a {
  display: inline-flex;
  align-items: center;
  gap: 0.5em;
}
header h1 a, header h1 a:hover {
  color: var(--color-text);
  text-decoration: none;
}

/* Sidebar */
#side-bar {
  width: var(--sidebar-width);
  float: left;
  clear: left;
  border-right: 1px solid var(--color-border);
  background-color: var(--color-bg);
  padding: 0 0 0.3em 0;
  margin: 0;
}
#side-bar ul {
  list-style: none;
  margin: 0;
  padding: 0;
}
#side-bar li { margin: 0; padding: 0.1ex 0; }
#side-bar li ul { padding-left: 0.6em; }
#side-bar a {
  color: var(--color-text);
  display: block;
  padding: 0.25em 1ex 0.25em 2mm;
  font-weight: bold;
  font-size: var(--font-sidebar);
  border-left: 0.2em solid transparent;
}
#side-bar a.current,
#side-bar a:hover {
  color: var(--color-text);
  background-color: var(--color-hover-bg);
  border-left: 0.2em solid var(--color-border);
  text-decoration: none;
}
#side-bar span {
  display: block;
  padding: 0.25em 1ex 0.25em 2mm;
  font-weight: bold;
  color: var(--color-text);
  font-size: var(--font-sidebar);
}
/* Collapsible directory nodes: native <details>/<summary>, no JS. */
#side-bar details { margin: 0; padding: 0; }
#side-bar summary {
  display: block;
  padding: 0.25em 1ex 0.25em 2mm;
  font-weight: bold;
  color: var(--color-text);
  font-size: var(--font-sidebar);
  cursor: pointer;
  list-style: none;
  border-left: 0.2em solid transparent;
}
#side-bar summary::-webkit-details-marker { display: none; }
#side-bar summary::before {
  content: "\25B8";          /* ▸ */
  display: inline-block;
  width: 0.9em;
  font-size: 0.85em;
}
#side-bar details[open] > summary::before { content: "\25BE"; }  /* ▾ */
#side-bar summary:hover,
#side-bar summary.current {
  background-color: var(--color-hover-bg);
  border-left: 0.2em solid var(--color-border);
}

/* Main content area */
article {
  max-width: var(--content-max-width);
  color: var(--color-text);
  background-color: transparent;
  text-align: justify;
  line-height: 1.5em;
  margin: 0 0 0 var(--sidebar-width);
  padding: 0.5mm 5mm 5mm 5mm;
  border-left: 1px solid var(--color-border);
}
article h1, article h2 {
  color: var(--color-text);
  font-size: var(--font-h1);
  font-weight: bold;
  margin: 1.5em 0 0.3em 0;
  padding: 0.5ex 0 0.5ex 0.6ex;
  border-bottom: 2px solid var(--color-border);
}
article h2 {
  font-size: var(--font-h2);
  border-bottom: 1px solid var(--color-border);
}
article h3 {
  color: var(--color-text);
  font-size: var(--font-h3);
  font-weight: bold;
  margin: 1.2em 0 0.3em 0;
}
article h4, article h5, article h6 {
  color: var(--color-text);
  font-weight: bold;
  margin: 1em 0 0.3em 0;
}
article h4 { font-size: var(--font-h4); }
article h5 { font-size: var(--font-h5); }
article h6 { font-size: var(--font-h6); font-style: italic; }
article p { margin: 1em 1ex; }
article ul, article ol { margin-left: 1ex; }
article pre {
  background: var(--color-code-bg);
  padding: 0.6em 0.9em;
  margin-left: 2em;
  border-left: 3px solid var(--color-border);
  font-family: var(--font-family-mono);
  font-size: var(--font-pre);
  overflow-x: auto;
}
article code {
  background: var(--color-code-bg);
  color: var(--color-text);
  padding: 0.05em 0.3em;
  border-radius: 2px;
  font-family: var(--font-family-mono);
  font-size: var(--font-code);
}
article pre code { background: none; padding: 0; color: inherit; }
article blockquote {
  border-left: 2px solid var(--color-border);
  color: var(--color-text);
  font-style: italic;
  margin: 1em 2em;
  padding-left: 1em;
}
article table { border: solid 1px var(--color-border); border-collapse: collapse; margin: 1em; }
article th { background-color: var(--color-bg); border: 1px solid var(--color-border);
             color: var(--color-text); padding: 0.3em 0.6em; text-align: center; }
article td { background-color: var(--color-bg); border: 1px solid var(--color-border);
             padding: 0.3em 0.6em; }
article img { max-width: 100%; height: auto; }

/* Footer */
footer {
  color: var(--color-text);
  background-color: var(--color-bg);
  padding: 1em;
  clear: both;
  border-top: 1px solid var(--color-border);
}
footer a { color: var(--color-text); }
.site-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: var(--font-footer);
}
.site-footer img { height: 1.2em; vertical-align: middle; }
.footer-left, .footer-center, .footer-right {
  display: flex; gap: 0.6em; align-items: center;
}

/* Mobile breakpoint: stack sidebar above article, drop the float layout.
   768px catches phones in portrait and small tablets; desktop rules above
   stay untouched. */
@media (max-width: 768px) {
  :root {
    --font-body:    100%;
    --font-nav:     1.2em;
    --font-banner:  1.4em;
    --sidebar-width: auto;
  }
  header nav { flex-wrap: wrap; padding: 0.25ex 0.6em; }
  .top-nav a { margin-left: 0; margin-right: 0.6em; }
  header h1 { padding-left: 2mm; }

  #side-bar {
    width: auto;
    float: none;
    clear: none;
    border-right: none;
    border-bottom: 1px solid var(--color-border);
  }
  article {
    max-width: 100%;
    margin: 0;
    border-left: none;
    padding: 0.5mm 3mm 5mm 3mm;
  }
  article p { margin: 1em 0; }
  article pre { margin-left: 0; }
  article blockquote { margin: 1em 0.5em; padding-left: 0.6em; }
  article table { margin: 1em 0; display: block; overflow-x: auto; }

  .site-footer { flex-wrap: wrap; gap: 0.4em; }
}