/* ===========================================================================
   EntroPy documentation — theme + layout
   =========================================================================== */
:root {
  --bg: #ffffff;
  --bg-soft: #f6f7fb;
  --bg-elev: #ffffff;
  --border: #e4e7ef;
  --text: #1c2333;
  --text-soft: #56607a;
  --muted: #8a93a6;
  --accent: #6d4aff;
  --accent-soft: #efeaff;
  --accent-2: #00b7c2;
  --code-bg: #f4f5fa;
  --code-text: #2d3346;
  --shadow: 0 1px 2px rgba(20, 26, 51, .06), 0 8px 24px rgba(20, 26, 51, .06);
  --radius: 12px;
  --maxw: 1180px;
  --sidebar-w: 270px;
  --header-h: 60px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
}

[data-theme="dark"] {
  --bg: #0e1018;
  --bg-soft: #141826;
  --bg-elev: #181c2c;
  --border: #262b3d;
  --text: #e7eaf3;
  --text-soft: #aab2c8;
  --muted: #6b7490;
  --accent: #9b86ff;
  --accent-soft: #221d3a;
  --accent-2: #2fd6e0;
  --code-bg: #141826;
  --code-text: #d6dcf0;
  --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 10px 30px rgba(0, 0, 0, .35);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 16px); }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  font-size: 16px;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 { line-height: 1.25; font-weight: 700; color: var(--text); }
h1 { font-size: 2.1rem; margin: 0 0 .4em; letter-spacing: -.02em; }
h2 { font-size: 1.55rem; margin: 2em 0 .6em; padding-bottom: .3em; border-bottom: 1px solid var(--border); }
h3 { font-size: 1.2rem; margin: 1.6em 0 .5em; }
h4 { font-size: 1.02rem; margin: 1.3em 0 .4em; }
p { margin: 0 0 1em; color: var(--text); }
ul, ol { padding-left: 1.4em; }
li { margin: .25em 0; }
hr { border: none; border-top: 1px solid var(--border); margin: 2em 0; }

code {
  font-family: var(--mono);
  font-size: .88em;
  background: var(--code-bg);
  color: var(--code-text);
  padding: .15em .4em;
  border-radius: 6px;
}

pre {
  background: var(--code-bg);
  color: var(--code-text);
  padding: 1em 1.2em;
  border-radius: var(--radius);
  overflow: auto;
  border: 1px solid var(--border);
  font-size: .86rem;
  line-height: 1.55;
}
pre code { background: none; padding: 0; font-size: inherit; }

table { border-collapse: collapse; width: 100%; margin: 1em 0; font-size: .93rem; }
th, td { text-align: left; padding: .55em .8em; border: 1px solid var(--border); vertical-align: top; }
th { background: var(--bg-soft); font-weight: 600; }
tbody tr:nth-child(even) { background: var(--bg-soft); }

blockquote {
  margin: 1em 0;
  padding: .6em 1em;
  border-left: 4px solid var(--accent);
  background: var(--accent-soft);
  border-radius: 0 8px 8px 0;
  color: var(--text-soft);
}

.callout {
  margin: 1.2em 0;
  padding: .9em 1.1em;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--bg-soft);
}
.callout.tip { border-left: 4px solid var(--accent-2); }
.callout.warn { border-left: 4px solid #f0a020; }
.callout h4 { margin: 0 0 .3em; }

.kbd { font-family: var(--mono); background: var(--bg-soft); border: 1px solid var(--border); border-bottom-width: 2px; border-radius: 5px; padding: .05em .4em; font-size: .82em; }

/* ------------------------------- header --------------------------------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  height: var(--header-h);
  display: flex; align-items: center; gap: 1rem;
  padding: 0 1.2rem;
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: .6rem; font-weight: 800; letter-spacing: -.01em; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand img { width: 30px; height: 30px; }
.brand .name { font-size: 1.15rem; }
.brand .tag { font-weight: 500; font-size: .72rem; color: var(--muted); border: 1px solid var(--border); padding: .05em .5em; border-radius: 999px; }

.header-spacer { flex: 1; }

.header-search { position: relative; }
.header-search input {
  width: 230px; max-width: 40vw;
  padding: .45em .9em .45em 2em;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-soft);
  color: var(--text);
  font-size: .9rem;
  outline: none;
}
.header-search input:focus { border-color: var(--accent); }
.header-search svg { position: absolute; left: .65em; top: 50%; transform: translateY(-50%); width: 16px; height: 16px; color: var(--muted); }

.icon-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 38px; height: 38px; border-radius: 9px;
  border: 1px solid var(--border); background: var(--bg-soft); color: var(--text-soft);
  cursor: pointer; font-size: 1rem;
}
.icon-btn:hover { color: var(--accent); border-color: var(--accent); }

.menu-toggle { display: none; }

/* ------------------------------- layout --------------------------------- */
.layout { display: flex; max-width: var(--maxw); margin: 0 auto; }

.sidebar {
  width: var(--sidebar-w);
  flex: 0 0 var(--sidebar-w);
  align-self: flex-start;
  position: sticky;
  top: var(--header-h);
  height: calc(100vh - var(--header-h));
  overflow-y: auto;
  padding: 1.4rem 1rem 3rem 1.2rem;
  border-right: 1px solid var(--border);
}
.sidebar nav { font-size: .92rem; }
.sidebar .group { margin-bottom: 1.2rem; }
.sidebar .group > .group-title {
  text-transform: uppercase; letter-spacing: .06em; font-size: .72rem;
  color: var(--muted); font-weight: 700; margin: 0 0 .4em; padding-left: .6rem;
}
.sidebar a {
  display: block; color: var(--text-soft); padding: .32em .6em; border-radius: 8px;
}
.sidebar a:hover { background: var(--bg-soft); color: var(--text); text-decoration: none; }
.sidebar a.active { background: var(--accent-soft); color: var(--accent); font-weight: 600; }

.content { flex: 1; min-width: 0; padding: 2.2rem 2.4rem 5rem; }
.content > .page-title { margin-top: 0; }

.footer {
  border-top: 1px solid var(--border);
  padding: 2rem 1.5rem;
  text-align: center;
  color: var(--muted);
  font-size: .88rem;
}
.footer a { color: var(--text-soft); }

/* ------------------------------- home ----------------------------------- */
.hero {
  max-width: var(--maxw); margin: 0 auto; padding: 4.5rem 1.5rem 3rem;
  text-align: center;
}
.hero .badge {
  display: inline-block; font-size: .8rem; color: var(--accent);
  background: var(--accent-soft); border: 1px solid color-mix(in srgb, var(--accent) 30%, transparent);
  padding: .3em .9em; border-radius: 999px; margin-bottom: 1.2rem; font-weight: 600;
}
.hero h1 { font-size: clamp(2.2rem, 5vw, 3.4rem); margin-bottom: .4em; }
.hero .lead { font-size: 1.2rem; color: var(--text-soft); max-width: 720px; margin: 0 auto 1.6em; }
.hero .cta { display: flex; gap: .8rem; justify-content: center; flex-wrap: wrap; }

.btn {
  display: inline-flex; align-items: center; gap: .4em;
  padding: .7em 1.4em; border-radius: 10px; font-weight: 600; font-size: .98rem;
  border: 1px solid var(--border); color: var(--text); background: var(--bg-elev);
}
.btn:hover { text-decoration: none; border-color: var(--accent); color: var(--accent); }
.btn.primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.btn.primary:hover { color: #fff; filter: brightness(1.08); }

.features { max-width: var(--maxw); margin: 0 auto; padding: 1rem 1.5rem 3rem; display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1.2rem; }
.feature { background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.3rem; box-shadow: var(--shadow); }
.feature h3 { margin-top: 0; font-size: 1.05rem; }
.feature p { color: var(--text-soft); margin-bottom: 0; font-size: .93rem; }
.feature .ico { font-size: 1.5rem; margin-bottom: .4rem; display: block; }

.home-code { max-width: var(--maxw); margin: 0 auto; padding: 0 1.5rem 4rem; }
.home-code .grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1.2rem; }
@media (max-width: 820px) { .home-code .grid { grid-template-columns: 1fr; } }

/* ------------------------------- misc ----------------------------------- */
.metrics-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: .9rem; margin: 1em 0; }
.metric-card { border: 1px solid var(--border); border-radius: 10px; padding: .8rem .9rem; background: var(--bg-elev); }
.metric-card .mname { font-family: var(--mono); font-size: .85rem; color: var(--accent); font-weight: 600; }
.metric-card .mdesc { color: var(--text-soft); font-size: .85rem; margin-top: .25em; }
.layer-tag { display: inline-block; font-size: .7rem; padding: .1em .5em; border-radius: 6px; background: var(--accent-soft); color: var(--accent); margin-right: .3em; }

.prevnext { display: flex; justify-content: space-between; gap: 1rem; margin-top: 3.5rem; border-top: 1px solid var(--border); padding-top: 1.4rem; }
.prevnext a { flex: 1; padding: 1rem; border: 1px solid var(--border); border-radius: 10px; color: var(--text); }
.prevnext a:hover { border-color: var(--accent); text-decoration: none; }
.prevnext .next { text-align: right; }
.prevnext .lbl { font-size: .75rem; color: var(--muted); display: block; }
.prevnext .ttl { font-weight: 600; }

/* search results overlay */
.search-results {
  position: absolute; top: calc(100% + 8px); right: 0; width: 360px; max-width: 90vw;
  background: var(--bg-elev); border: 1px solid var(--border); border-radius: 12px;
  box-shadow: var(--shadow); max-height: 60vh; overflow-y: auto; display: none; z-index: 60;
}
.search-results.open { display: block; }
.search-results a { display: block; padding: .7em .9em; border-bottom: 1px solid var(--border); color: var(--text); }
.search-results a:hover { background: var(--bg-soft); text-decoration: none; }
.search-results .sr-title { font-weight: 600; }
.search-results .sr-snippet { font-size: .82rem; color: var(--muted); }
.search-results .empty { padding: 1em; color: var(--muted); }

/* ------------------------------- responsive ----------------------------- */
@media (max-width: 920px) {
  .sidebar { position: fixed; top: var(--header-h); left: 0; z-index: 45; background: var(--bg); transform: translateX(-100%); transition: transform .2s; width: 80vw; max-width: 320px; }
  .sidebar.open { transform: translateX(0); }
  .menu-toggle { display: inline-flex; }
  .content { padding: 1.6rem 1.2rem 4rem; }
  .header-search input { width: 150px; }
}
.scrim { position: fixed; inset: var(--header-h) 0 0 0; background: rgba(0,0,0,.4); z-index: 44; display: none; }
.scrim.show { display: block; }