/* ---------------------------------------------------------
   Tokens
--------------------------------------------------------- */
:root{
  --bg:        #0F1115;
  --bg-panel:  #161920;
  --bg-panel-2:#1C2029;
  --line:      #262B35;
  --text:      #E7E5E0;
  --muted:     #8B92A0;
  --accent:    #7C9EFF;   /* git-graph line / links */
  --accent-dim:#4C5A99;
  --warn:      #F0A868;   /* troubleshooting / caution */
  --ok:        #7FD9A6;

  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --sans: "IBM Plex Sans", -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;

  --radius: 3px;
  --max-w: 780px;
}

*{ box-sizing: border-box; }

html{ scroll-behavior: smooth; }

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

::selection{ background:var(--accent); color:#0F1115; }

a{ color:var(--accent); text-decoration:none; }
a:hover{ text-decoration:underline; }
a:focus-visible, button:focus-visible{
  outline:2px solid var(--accent);
  outline-offset:2px;
}

/* ---------------------------------------------------------
   Header
--------------------------------------------------------- */
.site-header{
  border-bottom:1px solid var(--line);
  padding:28px 24px;
}
.site-header .inner{
  max-width: 920px;
  margin:0 auto;
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap:16px;
  flex-wrap:wrap;
}
.brand{
  font-family:var(--mono);
  font-weight:600;
  font-size:15px;
  letter-spacing:.02em;
  color:var(--text);
}
.brand::before{
  content:"$ ";
  color:var(--accent);
}
.site-header nav{
  display:flex;
  align-items:center;
  gap:6px;
}
.lang-pill{
  font-family:var(--mono);
  font-size:12px;
  color:var(--muted);
  background:transparent;
  border:1px solid var(--line);
  border-radius:999px;
  padding:3px 10px;
  text-decoration:none;
}
.lang-pill:hover{ color:var(--text); text-decoration:none; }
.lang-pill.active{
  color:var(--bg);
  background:var(--accent);
  border-color:var(--accent);
}

/* ---------------------------------------------------------
   Shell: sidebar nav + content
--------------------------------------------------------- */
.shell{
  max-width:1160px;
  margin:0 auto;
  padding:0 24px;
  display:block;
}
@media (min-width:900px){
  .shell{
    display:grid;
    grid-template-columns:250px minmax(0,1fr);
    gap:48px;
    align-items:start;
  }
}

.sidenav-wrap{
  margin:28px 0 8px;
  border:1px solid var(--line);
  border-radius:var(--radius);
  background:var(--bg-panel);
}
.sidenav-wrap summary{
  cursor:pointer;
  list-style:none;
  padding:12px 16px;
  font-family:var(--mono);
  font-size:13px;
  color:var(--text);
  display:flex;
  align-items:center;
  justify-content:space-between;
}
.sidenav-wrap summary::-webkit-details-marker{ display:none; }
.sidenav-wrap .chev{ color:var(--muted); transition:transform .15s ease; }
.sidenav-wrap[open] .chev{ transform:rotate(180deg); }

.sidenav-list{ padding:4px 16px 16px; }
.sidenav-title{
  font-family:var(--mono);
  font-size:11px;
  text-transform:uppercase;
  letter-spacing:.06em;
  color:var(--muted);
  margin:8px 0 10px;
}
.sidenav-topic{ margin-bottom:16px; }
.sidenav-topic-title{
  font-size:13px;
  font-weight:600;
  color:var(--text);
  margin:0 0 6px;
}
.sidenav-list ul{
  list-style:none;
  margin:0;
  padding:0;
  border-left:1px solid var(--line);
}
.sidenav-list li{ margin:0; }
.sidenav-list li a{
  display:block;
  padding:5px 0 5px 12px;
  font-size:13px;
  color:var(--muted);
  border-left:2px solid transparent;
  margin-left:-1px;
}
.sidenav-list li a:hover{ color:var(--text); text-decoration:none; }
.sidenav-list li.active a{
  color:var(--accent);
  border-left-color:var(--accent);
  font-weight:600;
}

@media (min-width:900px){
  .sidenav-wrap{
    position:sticky;
    top:24px;
    margin:56px 0;
  }
  .sidenav-wrap summary{ display:none; }
  .sidenav-wrap > *:not(summary){ display:block !important; }
}

/* ---------------------------------------------------------
   Language picker (root page)
--------------------------------------------------------- */
.picker{ text-align:center; margin:96px auto; }
.picker h1{ font-size:clamp(24px,4vw,34px); }
.picker-sep{ color:var(--muted); font-weight:400; }
.picker-choices{
  display:flex;
  gap:16px;
  justify-content:center;
  margin-top:32px;
  flex-wrap:wrap;
}
.picker-choice{
  display:flex;
  align-items:center;
  gap:10px;
  padding:16px 28px;
  border:1px solid var(--line);
  border-radius:var(--radius);
  background:var(--bg-panel);
  color:var(--text);
  text-decoration:none;
  font-size:16px;
  transition:border-color .15s ease, transform .15s ease;
}
.picker-choice:hover{
  border-color:var(--accent);
  transform:translateY(-2px);
  text-decoration:none;
}
.picker-flag{
  font-family:var(--mono);
  font-size:12px;
  padding:3px 8px;
  border-radius:999px;
  background:var(--accent);
  color:var(--bg);
}

/* ---------------------------------------------------------
   Hero (home page)
--------------------------------------------------------- */
.hero{
  max-width:920px;
  margin:64px auto 40px;
  padding:0 24px;
}
.hero .eyebrow{
  font-family:var(--mono);
  color:var(--accent);
  font-size:13px;
  letter-spacing:.06em;
  text-transform:uppercase;
  margin-bottom:14px;
}
.hero h1{
  font-family:var(--sans);
  font-weight:700;
  font-size:clamp(30px, 4.5vw, 46px);
  line-height:1.15;
  margin:0 0 18px;
  letter-spacing:-0.01em;
}
.hero p.lede{
  color:var(--muted);
  font-size:17px;
  max-width:60ch;
  margin:0 0 8px;
}
.hero code{
  font-family:var(--mono);
  background:var(--bg-panel);
  border:1px solid var(--line);
  padding:1px 6px;
  border-radius:var(--radius);
  font-size:.9em;
  color:var(--ok);
}

/* ---------------------------------------------------------
   Topic list (signature element) — one node per tutorial topic
--------------------------------------------------------- */
.topics{
  max-width:920px;
  margin:0 auto 80px;
  padding:0 24px;
  list-style:none;
}

.topic-card{
  position:relative;
  display:grid;
  grid-template-columns:40px 1fr;
  gap:0 20px;
}
.topic-card .rail{
  position:relative;
  display:flex;
  justify-content:center;
}
.topic-card .rail::before{
  content:"";
  position:absolute;
  top:0;
  bottom:0;
  width:2px;
  background:var(--line);
}
.topic-card:first-child .rail::before{ top:18px; }
.topic-card:last-child .rail::before{ bottom:calc(100% - 18px); }

.topic-card .node{
  position:relative;
  z-index:1;
  margin-top:14px;
  width:14px;
  height:14px;
  border-radius:50%;
  background:var(--bg);
  border:2px solid var(--accent);
}

.topic-body{ margin:6px 0; }

.topic-card a.entry{
  display:block;
  padding:16px 18px;
  margin-bottom:0;
  border:1px solid var(--line);
  border-radius:var(--radius);
  background:var(--bg-panel);
  text-decoration:none;
  color:var(--text);
  transition:border-color .15s ease, transform .15s ease;
}
.topic-card a.entry:hover{
  border-color:var(--accent);
  transform:translateX(2px);
}
.topic-card .hash{
  font-family:var(--mono);
  font-size:12px;
  color:var(--accent);
}
.topic-card .entry h3{
  font-size:17px;
  margin:4px 0 4px;
  font-weight:600;
}
.topic-card .entry p{
  margin:0;
  color:var(--muted);
  font-size:14px;
}
.topic-card .tags{
  display:flex;
  gap:6px;
  margin-top:10px;
  flex-wrap:wrap;
}
.tag{
  font-family:var(--mono);
  font-size:11px;
  padding:2px 8px;
  border-radius:999px;
  border:1px solid var(--line);
  color:var(--muted);
}

/* ---------------------------------------------------------
   Guide page
--------------------------------------------------------- */
.guide{
  max-width:var(--max-w);
  margin:0 auto;
  padding:56px 24px 100px;
}
.guide .crumbs{
  font-family:var(--mono);
  font-size:13px;
  color:var(--muted);
  margin-bottom:24px;
}
.guide .crumbs a{ color:var(--muted); }
.guide .crumbs a:hover{ color:var(--accent); }

.guide h1{
  font-size:clamp(26px,4vw,36px);
  line-height:1.2;
  margin:0 0 8px;
}
.guide .dek{
  color:var(--muted);
  font-size:16px;
  margin:0 0 40px;
}

.guide h2{
  font-size:22px;
  margin:48px 0 14px;
  padding-top:8px;
  border-top:1px solid var(--line);
}
.guide h2:first-of-type{ border-top:none; padding-top:0; }
.guide h3{ font-size:17px; margin:28px 0 10px; }

.guide p{ margin:0 0 16px; }
.guide ul, .guide ol{ margin:0 0 16px; padding-left:22px; }
.guide li{ margin-bottom:6px; }

.guide code{
  font-family:var(--mono);
  background:var(--bg-panel);
  border:1px solid var(--line);
  padding:1px 6px;
  border-radius:var(--radius);
  font-size:.88em;
  color:var(--ok);
}
.guide pre{
  background:var(--bg-panel);
  border:1px solid var(--line);
  border-radius:var(--radius);
  padding:16px 18px;
  overflow-x:auto;
  margin:0 0 20px;
}
.guide pre code{
  background:none;
  border:none;
  padding:0;
  color:var(--text);
  font-size:13.5px;
  line-height:1.6;
}

.guide blockquote{
  margin:0 0 20px;
  padding:12px 16px;
  border-left:3px solid var(--warn);
  background:var(--bg-panel);
  color:var(--muted);
  border-radius:0 var(--radius) var(--radius) 0;
}
.guide blockquote p:last-child{ margin-bottom:0; }

.guide table{
  width:100%;
  border-collapse:collapse;
  margin:0 0 20px;
  font-size:14px;
}
.guide th, .guide td{
  text-align:left;
  padding:8px 12px;
  border:1px solid var(--line);
}
.guide th{
  font-family:var(--mono);
  color:var(--muted);
  font-weight:500;
  background:var(--bg-panel);
}

.pager{
  display:flex;
  justify-content:space-between;
  gap:16px;
  margin-top:56px;
  padding-top:24px;
  border-top:1px solid var(--line);
  font-family:var(--mono);
  font-size:13px;
}
.pager a{ color:var(--text); }
.pager .dir{ display:block; color:var(--muted); font-size:11px; margin-bottom:4px; }
.pager .next{ text-align:right; margin-left:auto; }

/* ---------------------------------------------------------
   Footer
--------------------------------------------------------- */
.site-footer{
  border-top:1px solid var(--line);
  padding:28px 24px 60px;
  text-align:center;
  color:var(--muted);
  font-family:var(--mono);
  font-size:12px;
}

@media (max-width:560px){
  .commit{ grid-template-columns:26px 1fr; gap:0 12px; }
  .commit .node{ width:11px; height:11px; }
}