:root{
  --ink:#19313a; --teal:#247c78; --teal-d:#1c6461; --teal-soft:#e6f1ee; --muted:#71807d;
  --border:#dce5df; --background:#edf2ee; --side:#f8faf6; --card:#ffffff;
  --accent:#d9653b; --accent-soft:#fbede6;
  --shadow:0 1px 2px rgba(25,49,58,.05),0 6px 18px rgba(25,49,58,.05);
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    --ink:#dfe9e6; --teal:#4fb3ac; --teal-d:#6cc5be; --teal-soft:#1d3634; --muted:#90a19d;
    --border:#2c3c3a; --background:#121a19; --side:#172120; --card:#18211f;
    --accent:#f08a62; --accent-soft:#3a2720; --shadow:none;
  }
}
:root[data-theme="dark"]{
  --ink:#dfe9e6; --teal:#4fb3ac; --teal-d:#6cc5be; --teal-soft:#1d3634; --muted:#90a19d;
  --border:#2c3c3a; --background:#121a19; --side:#172120; --card:#18211f;
  --accent:#f08a62; --accent-soft:#3a2720; --shadow:none;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--background);color:var(--ink);font:15px/1.6 system-ui,-apple-system,"Segoe UI",sans-serif;-webkit-font-smoothing:antialiased}
a{color:var(--teal)}
button{font:inherit;color:inherit;cursor:pointer}
a:focus-visible,button:focus-visible{outline:3px solid #247c7860;outline-offset:3px}

/* ---------- top bar ---------- */
.bar{position:sticky;top:0;z-index:5;display:flex;align-items:center;gap:6px;padding:12px 28px;background:color-mix(in srgb,var(--side) 88%,transparent);backdrop-filter:blur(8px);border-bottom:1px solid var(--border)}
.logo{display:flex;align-items:center;gap:10px;text-decoration:none;color:var(--ink)}
.logo svg{width:34px;height:34px}
.logo b{display:block;font-size:26px;font-weight:750;letter-spacing:-.05em;line-height:1}
.logo i{font-style:normal;color:var(--accent)}
.logo small{display:block;font-size:8px;font-weight:700;letter-spacing:.16em;text-transform:uppercase;color:var(--muted);margin-top:6px}
.sp{flex:1}
.tbtn{background:none;border:0;padding:6px 10px;border-radius:8px;font-size:13px;color:var(--muted);text-decoration:none}
.tbtn:hover{color:var(--ink);background:var(--teal-soft)}

/* ---------- hero ---------- */
main{max-width:1120px;margin:0 auto;padding:0 28px}
.hero{padding:72px 0 48px;max-width:780px}
.eyebrow{margin:0 0 14px;font-size:11px;font-weight:750;letter-spacing:.14em;text-transform:uppercase;color:var(--teal)}
h1{margin:0;font-size:clamp(30px,4.6vw,46px);line-height:1.12;letter-spacing:-.03em;font-weight:750;text-wrap:balance}
.lead{margin:18px 0 0;font-size:17px;color:var(--muted);max-width:680px}
.hero-actions{display:flex;flex-wrap:wrap;align-items:center;gap:14px 20px;margin-top:28px}
.btn{display:inline-block;background:var(--teal);color:#fff;text-decoration:none;font-weight:650;font-size:14px;padding:12px 20px;border-radius:9px}
.btn:hover{background:var(--teal-d)}
:root[data-theme="dark"] .btn{color:#0f1716}
@media (prefers-color-scheme: dark){:root:not([data-theme="light"]) .btn{color:#0f1716}}
.note{font-size:13px;color:var(--muted)}

/* ---------- course cards ---------- */
.courses{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px;scroll-margin-top:80px}
.course{display:flex;flex-direction:column;background:var(--card);border:1px solid var(--border);border-radius:14px;padding:22px 22px 20px;text-decoration:none;color:var(--ink);box-shadow:var(--shadow);transition:transform .15s,border-color .15s}
.course:hover{transform:translateY(-2px);border-color:var(--teal)}
.course-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px}
.course-top svg{width:38px;height:38px;fill:none;stroke:var(--teal);stroke-width:1.5;stroke-linecap:round;stroke-linejoin:round}
.tag{font-size:10px;font-weight:650;color:var(--teal);border:1px solid var(--border);border-radius:30px;padding:3px 9px;background:var(--teal-soft)}
.course h2{margin:0 0 8px;font-size:20px;letter-spacing:-.02em;line-height:1.25}
.course p{margin:0;font-size:14px;color:var(--muted);flex:1}
.course dl{display:flex;gap:26px;margin:18px 0 16px;padding-top:16px;border-top:1px solid var(--border)}
.course dl div{margin:0}
.course dt{font-size:24px;font-weight:700;color:var(--teal);line-height:1.1}
.course dd{margin:2px 0 0;font-size:12px;color:var(--muted)}
.go{font-size:13px;font-weight:650;color:var(--teal)}

/* ---------- how ---------- */
.how{padding:64px 0 8px;scroll-margin-top:60px}
.how h2,.facts b{letter-spacing:-.02em}
.how h2{margin:0 0 20px;font-size:24px}
.flow{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}
.flow li{background:var(--card);border:1px solid var(--border);border-radius:12px;padding:16px 16px 14px;position:relative}
.flow li:first-child{box-shadow:inset 0 3px var(--teal)}
.flow span{font-size:11px;font-weight:750;color:var(--teal)}
.flow b{display:block;margin:6px 0 4px;font-size:16px}
.flow p{margin:0;font-size:13px;color:var(--muted)}

.facts{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;padding:44px 0 64px}
.facts div{border-left:3px solid var(--accent);padding:2px 0 2px 14px}
.facts b{font-size:15px}
.facts p{margin:4px 0 0;font-size:13px;color:var(--muted)}

.foot{display:flex;flex-wrap:wrap;justify-content:space-between;gap:8px 20px;max-width:1120px;margin:0 auto;padding:22px 28px 30px;border-top:1px solid var(--border);font-size:12px;color:var(--muted)}

/* ---------- 404 ---------- */
.lost{min-height:70vh;display:grid;place-content:center;text-align:center;padding:40px 16px}
.lost b{font-size:64px;font-weight:750;color:var(--teal);letter-spacing:-.04em;line-height:1}
.lost p{color:var(--muted);margin:12px 0 22px}
.lost .btn{justify-self:center}

@media (max-width:900px){
  .courses{grid-template-columns:1fr}
  .flow{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:600px){
  .bar{padding:10px 16px}
  main{padding:0 16px}
  .foot{padding:20px 16px 26px}
  .hide-s{display:none}
  .hero{padding:40px 0 32px}
  .lead{font-size:15px}
  .flow,.facts{grid-template-columns:1fr}
}