:root{
  --bg:#f7f6f3; --panel:#ffffff; --ink:#1c1a17; --ink-soft:#5b564d; --line:#e6e2da;
  --accent:#0f172a; --gold:#b8862c; --gold-soft:#f4e9d6;
  --code-bg:#f1efe9; --shadow:0 1px 3px rgba(20,16,8,.08); --danger:#b3441e;
  --track-beginner:#3b6e8f; --track-intermediate:#4c7a4c; --track-advanced:#a35d2e; --track-expert:#7a3b8f;
}
@media (prefers-color-scheme: dark){
  :root{
    --bg:#15130f; --panel:#1e1b16; --ink:#f1ede4; --ink-soft:#b9b2a4; --line:#332e26;
    --accent:#e9e4d8; --gold:#e0b45c; --gold-soft:#3a2f1c;
    --code-bg:#26221b; --shadow:0 1px 3px rgba(0,0,0,.4); --danger:#e0805a;
    --track-beginner:#7fb2d6; --track-intermediate:#8ec98e; --track-advanced:#e0a06a; --track-expert:#c98ee0;
  }
}
*{box-sizing:border-box;}
html,body{margin:0; padding:0;}
body{background:var(--bg); color:var(--ink); font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif; line-height:1.5;}
a{color:var(--gold);}
button{font:inherit;}
.wrap{max-width:1180px; margin:0 auto; padding:0 20px;}
header.top{border-bottom:1px solid var(--line); padding:14px 0; position:sticky; top:0; background:var(--bg); z-index:10;}
header.top .wrap{display:flex; align-items:center; justify-content:space-between; gap:12px; flex-wrap:wrap;}
.brand{display:flex; align-items:center; gap:10px; font-weight:700; font-size:17px; cursor:pointer; text-decoration:none; color:var(--ink);}
.brand .mark{width:28px; height:28px; border-radius:7px; background:linear-gradient(135deg,var(--accent),var(--gold)); flex:none;}
nav.topnav{display:flex; gap:16px; align-items:center; font-size:14px; flex-wrap:wrap;}
nav.topnav a{background:none; border:none; color:var(--ink-soft); font:inherit; cursor:pointer; padding:6px 4px; text-decoration:none;}
nav.topnav a:hover, nav.topnav a.active{color:var(--ink); font-weight:600;}
.who{font-size:13px; color:var(--ink-soft); display:flex; align-items:center; gap:10px;}
.who b{color:var(--ink);}
.linkbtn{background:none;border:none;color:var(--ink-soft);text-decoration:underline;cursor:pointer;font-size:13px;padding:0;}

.hero{padding:56px 0 36px;}
.hero h1{font-size:clamp(28px,5vw,44px); margin:0 0 12px; letter-spacing:-.02em;}
.hero p.lead{font-size:17px; color:var(--ink-soft); max-width:680px; margin:0 0 22px;}
.cta-row{display:flex; gap:12px; flex-wrap:wrap; margin-bottom:8px;}
.btn{display:inline-block; padding:11px 20px; border-radius:9px; font-weight:600; font-size:14px; cursor:pointer; border:1px solid transparent; text-decoration:none; background:none;}
.btn-primary{background:var(--gold); color:#1c1608;}
.btn-primary:hover{filter:brightness(1.06);}
.btn-ghost{background:transparent; border-color:var(--line); color:var(--ink);}
.btn-ghost:hover{border-color:var(--ink-soft);}
.btn-danger{background:transparent; border-color:var(--danger); color:var(--danger);}
.btn-sm{padding:6px 12px; font-size:12.5px; border-radius:7px;}

.track-grid{display:grid; grid-template-columns:repeat(auto-fit,minmax(230px,1fr)); gap:16px; margin:30px 0 50px;}
.track-card{background:var(--panel); border:1px solid var(--line); border-radius:14px; padding:18px; box-shadow:var(--shadow); cursor:pointer; transition:transform .12s ease; text-decoration:none; display:block; color:var(--ink);}
.track-card:hover{transform:translateY(-2px);}
.track-card .tlabel{display:inline-block; font-size:12px; font-weight:700; text-transform:uppercase; letter-spacing:.06em; padding:3px 9px; border-radius:999px; margin-bottom:10px; color:#fff;}
.track-card h3{margin:0 0 8px; font-size:18px;}
.track-card p{margin:0 0 14px; color:var(--ink-soft); font-size:13.5px; min-height:36px;}
.progress-bar{height:6px; background:var(--line); border-radius:99px; overflow:hidden;}
.progress-bar > div{height:100%; background:var(--gold); border-radius:99px;}
.track-card .pct{font-size:12px; color:var(--ink-soft); margin-top:6px;}

.pillars{display:grid; grid-template-columns:repeat(auto-fit,minmax(220px,1fr)); gap:14px; margin:14px 0;}
.pillar{background:var(--panel); border:1px solid var(--line); border-radius:10px; padding:14px;}
.pillar b{display:block; margin-bottom:4px;}

.authwrap{max-width:400px; margin:60px auto; padding:0 20px;}
.authwrap h2{margin:0 0 6px;}
.authwrap p.sub{color:var(--ink-soft); font-size:13.5px; margin:0 0 22px;}
.field{margin-bottom:14px;}
.field label{display:block; font-size:12.5px; font-weight:600; margin-bottom:5px; color:var(--ink-soft);}
.field input, .field select, .field textarea{width:100%; padding:10px 12px; border-radius:8px; border:1px solid var(--line); background:var(--panel); color:var(--ink); font:inherit;}
.field textarea{resize:vertical; font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace; font-size:12.5px;}
.formerr{background:#fbeae3; color:var(--danger); border-radius:8px; padding:9px 12px; font-size:13px; margin-bottom:14px;}
@media (prefers-color-scheme: dark){ .formerr{background:#3a2015;} }
.formok{background:var(--gold-soft); border-radius:8px; padding:9px 12px; font-size:13px; margin-bottom:14px;}

.page{padding:30px 0 60px;}
.page h2{margin:0 0 4px;}
.page p.sub{color:var(--ink-soft); font-size:13.5px; margin:0 0 22px;}

.course{display:flex; gap:0; align-items:flex-start; min-height:70vh;}
.sidebar{width:290px; flex:none; border-right:1px solid var(--line); padding:18px 14px 40px 0; position:sticky; top:57px; max-height:calc(100vh - 57px); overflow-y:auto;}
.sidebar .track-switch{display:flex; flex-wrap:wrap; gap:6px; margin-bottom:14px;}
.sidebar .track-switch a{font-size:12.5px; padding:6px 10px; border-radius:7px; border:1px solid var(--line); background:var(--panel); color:var(--ink-soft); cursor:pointer; text-decoration:none;}
.sidebar .track-switch a.active{background:var(--gold); color:#1c1608; border-color:transparent; font-weight:700;}
.track-progress-line{font-size:12px; color:var(--ink-soft); margin-bottom:14px;}
.modblock{margin-bottom:16px;}
.modblock h4{font-size:12.5px; text-transform:uppercase; letter-spacing:.04em; color:var(--ink-soft); margin:0 0 8px;}
.lesson-row{display:flex; align-items:flex-start; gap:8px; padding:6px 6px; border-radius:7px; cursor:pointer; font-size:13.5px; text-decoration:none; color:var(--ink);}
.lesson-row:hover{background:var(--gold-soft);}
.lesson-row.active{background:var(--gold-soft); font-weight:700;}
.lesson-row input[type=checkbox]{margin-top:3px; accent-color:var(--gold); flex:none;}
main.content{flex:1; min-width:0; padding:26px 32px 80px;}
main.content .crumb{font-size:12.5px; color:var(--ink-soft); margin-bottom:6px;}
main.content h2.ltitle{margin:0 0 18px; font-size:26px;}
main.content h4{margin:26px 0 8px; font-size:15px;}
.pbnum{color:var(--ink-soft); font-size:12.5px; margin:0 0 4px; text-transform:uppercase; letter-spacing:.05em;}
.lesson-nav{display:flex; justify-content:space-between; margin-top:34px; padding-top:18px; border-top:1px solid var(--line); gap:10px; flex-wrap:wrap;}
.stacktable{width:100%; border-collapse:collapse; margin:10px 0 16px; font-size:13.5px; display:block; overflow-x:auto;}
.stacktable th,.stacktable td{border:1px solid var(--line); padding:8px 10px; text-align:left; vertical-align:top;}
.stacktable th{background:var(--code-bg);}
.promptbox{background:var(--code-bg); border:1px solid var(--line); border-radius:8px; padding:10px 14px; margin:10px 0;}
.promptbox pre{white-space:pre-wrap; font-size:12.5px; margin:6px 0 0; font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;}
code{background:var(--code-bg); padding:1px 5px; border-radius:4px; font-size:.92em;}

table.datatable{width:100%; border-collapse:collapse; font-size:13.5px; background:var(--panel); border:1px solid var(--line); border-radius:10px; overflow:hidden;}
table.datatable th, table.datatable td{border-bottom:1px solid var(--line); padding:9px 10px; text-align:left; vertical-align:top;}
table.datatable th{background:var(--code-bg); font-size:12px; text-transform:uppercase; letter-spacing:.04em; color:var(--ink-soft);}
table.datatable tr:last-child td{border-bottom:none;}
.tablewrap{overflow-x:auto;}
.pill{display:inline-block; padding:2px 9px; border-radius:999px; font-size:11.5px; font-weight:600; background:var(--gold-soft); color:var(--ink);}
.toolbar{display:flex; justify-content:space-between; align-items:center; gap:10px; margin-bottom:16px; flex-wrap:wrap;}

.card{background:var(--panel); border:1px solid var(--line); border-radius:12px; padding:18px; box-shadow:var(--shadow); margin-bottom:16px;}
.card h3{margin:0 0 4px; font-size:15px;}
.card .meta{font-size:12px; color:var(--ink-soft); margin-bottom:10px;}
.card pre{white-space:pre-wrap; font-size:12.5px; background:var(--code-bg); padding:10px; border-radius:7px; margin:0;}
.cardgrid{display:grid; grid-template-columns:repeat(auto-fill,minmax(280px,1fr)); gap:14px;}
.rowbtns{display:flex; gap:8px; margin-top:10px;}

.modal-backdrop{position:fixed; inset:0; background:rgba(20,16,8,.45); display:flex; align-items:flex-start; justify-content:center; padding:40px 16px; z-index:50; overflow-y:auto;}
.modal{background:var(--panel); border-radius:12px; padding:22px; max-width:480px; width:100%; box-shadow:0 8px 30px rgba(0,0,0,.3);}
.modal h3{margin:0 0 14px;}

footer.site{border-top:1px solid var(--line); padding:26px 0; text-align:center; color:var(--ink-soft); font-size:12.5px;}

@media (max-width:800px){
  .course{flex-direction:column;}
  .sidebar{width:100%; border-right:none; border-bottom:1px solid var(--line); position:static; max-height:none; padding-bottom:10px;}
  main.content{padding:22px 4px 60px;}
}