/* LMS v3 — shared design system for the student site.
   Brand tokens mirror the course player so the whole experience reads as one system.
   Light + dark, responsive, no build step. */
:root{
  --bg:#f6f7f9; --surface:#fff; --surface-2:#fbfcfd; --ink:#1c2530; --muted:#5b6675;
  --line:#e3e7ec; --accent:#0e7c66; --accent-2:#0b6353; --accent-ink:#fff;
  --warn:#b45309; --tip:#0369a1; --danger:#c0392b; --ok:#0e7c66;
  --radius:14px; --radius-sm:10px;
  --shadow:0 1px 3px rgba(16,24,40,.06),0 8px 24px rgba(16,24,40,.06);
  --maxw:1080px; --font:'Inter',system-ui,-apple-system,Segoe UI,Roboto,sans-serif;
}
@media (prefers-color-scheme:dark){:root{
  --bg:#0f141a; --surface:#161d26; --surface-2:#1b2430; --ink:#e7ecf2; --muted:#93a1b2;
  --line:#28323e; --accent:#2bb397; --accent-2:#25a087; --shadow:0 1px 3px rgba(0,0,0,.3),0 8px 24px rgba(0,0,0,.35);
}}
*{box-sizing:border-box}
html,body{margin:0}
body{font-family:var(--font);background:var(--bg);color:var(--ink);line-height:1.55;
  -webkit-font-smoothing:antialiased}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* ── header / nav ── */
.nav{position:sticky;top:0;z-index:20;background:color-mix(in srgb,var(--surface) 88%,transparent);
  backdrop-filter:saturate(1.4) blur(8px);border-bottom:1px solid var(--line)}
.nav .wrap{display:flex;align-items:center;gap:18px;height:62px}
.brand{font-weight:800;font-size:18px;color:var(--ink);letter-spacing:-.01em;white-space:nowrap}
.brand span{color:var(--accent)}
.nav .spacer{flex:1}
.nav a.navlink{color:var(--muted);font-weight:600;font-size:14px}
.nav a.navlink:hover{color:var(--ink);text-decoration:none}
.cartbadge{display:inline-flex;align-items:center;gap:6px}
.cartbadge .count{background:var(--accent);color:var(--accent-ink);border-radius:99px;
  font-size:11px;font-weight:700;min-width:18px;height:18px;display:inline-grid;place-items:center;padding:0 5px}

/* ── buttons ── */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;cursor:pointer;
  font-family:inherit;font-weight:600;font-size:14px;padding:10px 18px;border-radius:var(--radius-sm);
  border:1px solid transparent;background:var(--accent);color:var(--accent-ink);transition:.15s}
.btn:hover{background:var(--accent-2);text-decoration:none}
.btn.secondary{background:transparent;color:var(--ink);border-color:var(--line)}
.btn.secondary:hover{background:var(--surface-2)}
.btn.ghost{background:transparent;color:var(--accent);padding:8px 10px}
.btn:disabled{opacity:.5;cursor:not-allowed}
.btn.block{width:100%}
.btn.lg{padding:13px 24px;font-size:15px}

/* ── layout bits ── */
.hero{padding:56px 0 34px;text-align:center}
.hero h1{font-size:clamp(28px,4vw,42px);line-height:1.1;letter-spacing:-.02em;margin:0 0 12px}
.hero p{color:var(--muted);font-size:17px;max-width:620px;margin:0 auto}
.section{padding:14px 0 40px}
.section h2{font-size:22px;letter-spacing:-.01em;margin:26px 0 4px}
.section .sub{color:var(--muted);font-size:14px;margin:0 0 16px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:18px}

/* ── cards ── */
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  box-shadow:var(--shadow);padding:20px;display:flex;flex-direction:column;gap:10px;transition:.15s}
.card:hover{transform:translateY(-2px)}
.card .eyebrow{font-size:12px;font-weight:700;text-transform:uppercase;letter-spacing:.05em;color:var(--accent)}
.card h3{margin:0;font-size:17px;line-height:1.3;letter-spacing:-.01em}
.card .desc{color:var(--muted);font-size:14px;flex:1}
.card .meta{display:flex;flex-wrap:wrap;gap:8px;font-size:12px;color:var(--muted)}
.chip{background:var(--surface-2);border:1px solid var(--line);border-radius:99px;padding:3px 10px;font-size:12px;color:var(--muted)}
.card .foot{display:flex;align-items:center;justify-content:space-between;margin-top:6px;gap:12px}
.price{font-weight:800;font-size:20px;color:var(--ink)}
.price small{font-weight:600;font-size:12px;color:var(--muted)}

/* ── forms / panels ── */
.panel{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  box-shadow:var(--shadow);padding:26px}
.formrow{margin:0 0 14px}
.formrow label{display:block;font-size:13px;font-weight:600;margin:0 0 6px}
.formrow input,.formrow select,.formrow textarea{width:100%;padding:11px 13px;border-radius:var(--radius-sm);
  border:1px solid var(--line);background:var(--surface-2);color:var(--ink);font-family:inherit;font-size:15px}
.formrow input:focus,.formrow select:focus{outline:2px solid var(--accent);border-color:transparent}
.center-narrow{max-width:440px;margin:40px auto}
.msg{font-size:14px;padding:10px 12px;border-radius:var(--radius-sm);margin:0 0 14px}
.msg.err{background:color-mix(in srgb,var(--danger) 12%,transparent);color:var(--danger)}
.msg.ok{background:color-mix(in srgb,var(--ok) 12%,transparent);color:var(--ok)}
.muted{color:var(--muted)}
.loading{padding:60px;text-align:center;color:var(--muted)}
.footer{border-top:1px solid var(--line);margin-top:40px;padding:26px 0;color:var(--muted);font-size:13px;text-align:center}