:root{
  --navy:#071B34;
  --navy-card:#0C2748;
  --navy-line:#16365E;
  --ink:#EAF4FB;
  --muted:#9FB6CC;
  --teal:#27D3E8;
  --green:#34D399;
  --amber:#F59E0B;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  background:var(--navy);
  color:var(--ink);
  font-family:"Inter",system-ui,-apple-system,sans-serif;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
.accent{color:var(--teal)}
.morse{font-family:"JetBrains Mono",monospace;color:var(--teal);letter-spacing:.15em}

/* layout */
.section{max-width:1080px;margin:0 auto;padding:88px 24px}
.section-title{font-size:clamp(1.8rem,4vw,2.6rem);font-weight:800;letter-spacing:-.02em;line-height:1.1}
.section-sub{color:var(--muted);font-size:1.08rem;max-width:60ch;margin-top:14px}
.section-sub.center{margin-left:auto;margin-right:auto;text-align:center}

/* nav */
.nav{
  position:sticky;top:0;z-index:50;
  display:flex;align-items:center;gap:24px;
  padding:14px 24px;
  background:rgba(7,27,52,.78);
  backdrop-filter:blur(12px);
  border-bottom:1px solid var(--navy-line);
}
.brand{display:flex;align-items:center;gap:11px;font-weight:700}
.brand-mark{height:38px;width:auto;display:block}
.brand-text{font-size:1.02rem;letter-spacing:.01em}
.brand-text b{color:var(--teal);font-weight:700}
.nav-links{display:flex;gap:26px;margin-left:auto;font-size:.95rem;color:var(--muted)}
.nav-links a:hover{color:var(--white)}

/* buttons */
.btn{
  display:inline-flex;align-items:center;justify-content:center;
  font-weight:600;font-size:1rem;
  padding:13px 24px;border-radius:11px;
  transition:transform .12s ease,box-shadow .2s ease,background .2s ease;
  white-space:nowrap;
}
.btn-sm{padding:9px 18px;font-size:.92rem;border-radius:9px}
.btn-primary{background:var(--teal);color:#042233;box-shadow:0 6px 20px rgba(39,211,232,.28)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 10px 28px rgba(39,211,232,.4)}
.btn-ghost{border:1.5px solid var(--navy-line);color:var(--ink)}
.btn-ghost:hover{border-color:var(--teal);color:var(--teal)}

/* hero */
.hero{
  max-width:1080px;margin:0 auto;
  padding:80px 24px 60px;
  display:grid;grid-template-columns:1.15fr .85fr;gap:48px;align-items:center;
}
.eyebrow{font-size:.9rem;color:var(--muted);font-weight:500;letter-spacing:.04em;margin-bottom:18px}
.hero h1{font-size:clamp(2.4rem,6vw,4rem);font-weight:800;letter-spacing:-.03em;line-height:1.04}
.lede{color:var(--muted);font-size:1.15rem;margin-top:22px;max-width:48ch}
.hero-actions{display:flex;gap:14px;margin-top:32px;flex-wrap:wrap}
.hero-actions.center{justify-content:center}
.tagline{margin-top:30px;font-family:"JetBrains Mono",monospace;font-size:1.05rem;color:var(--muted)}

.hero-art{position:relative;display:flex;flex-direction:column;align-items:center;gap:28px}
.hero-mark{width:min(320px,80%);height:auto;display:block;filter:drop-shadow(0 12px 40px rgba(39,211,232,.25))}
.waveform{display:flex;align-items:center;gap:5px;height:48px}
.waveform span{
  width:5px;border-radius:3px;background:var(--teal);opacity:.85;
  animation:wave 1.1s ease-in-out infinite;
}
.waveform span:nth-child(odd){animation-duration:1.4s}
.waveform span:nth-child(3n){animation-duration:.9s;background:var(--green)}
.waveform span:nth-child(1){height:14px;animation-delay:-.2s}
.waveform span:nth-child(2){height:28px;animation-delay:-.5s}
.waveform span:nth-child(3){height:40px;animation-delay:-.1s}
.waveform span:nth-child(4){height:22px;animation-delay:-.7s}
.waveform span:nth-child(5){height:34px;animation-delay:-.3s}
.waveform span:nth-child(6){height:18px;animation-delay:-.9s}
.waveform span:nth-child(7){height:44px;animation-delay:-.15s}
.waveform span:nth-child(8){height:26px;animation-delay:-.6s}
.waveform span:nth-child(9){height:38px;animation-delay:-.4s}
.waveform span:nth-child(10){height:16px;animation-delay:-.8s}
.waveform span:nth-child(11){height:30px;animation-delay:-.25s}
.waveform span:nth-child(12){height:42px;animation-delay:-.55s}
.waveform span:nth-child(13){height:20px;animation-delay:-.35s}
.waveform span:nth-child(14){height:36px;animation-delay:-.75s}
.waveform span:nth-child(15){height:24px;animation-delay:-.1s}
.waveform span:nth-child(16){height:40px;animation-delay:-.5s}
.waveform span:nth-child(17){height:14px;animation-delay:-.65s}
.waveform span:nth-child(18){height:32px;animation-delay:-.2s}
@keyframes wave{0%,100%{transform:scaleY(.4)}50%{transform:scaleY(1)}}

/* cards / grids */
.grid{display:grid;gap:18px;margin-top:42px}
.features{grid-template-columns:repeat(3,1fr)}
.card{
  background:var(--navy-card);
  border:1px solid var(--navy-line);
  border-radius:16px;padding:26px;
  transition:transform .15s ease,border-color .2s ease;
}
.card:hover{transform:translateY(-4px);border-color:var(--teal)}
.card-icon{
  font-size:1.4rem;width:50px;height:50px;border-radius:12px;
  display:flex;align-items:center;justify-content:center;
  background:rgba(39,211,232,.12);color:var(--teal);
  font-family:"JetBrains Mono",monospace;margin-bottom:16px;
}
.card-icon svg{width:25px;height:25px}
.card h3{font-size:1.15rem;margin-bottom:8px}
.card p{color:var(--muted);font-size:.98rem}

/* showcase */
.showcase{display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center}
.checklist{list-style:none;margin-top:24px;display:flex;flex-direction:column;gap:12px}
.checklist li{position:relative;padding-left:30px;color:var(--ink)}
.checklist li::before{
  content:"\2713";position:absolute;left:0;top:0;
  color:var(--green);font-weight:700;
  background:rgba(52,211,153,.14);width:22px;height:22px;border-radius:6px;
  display:flex;align-items:center;justify-content:center;font-size:.8rem;
}
.showcase-ui{display:flex;gap:18px;justify-content:center}
.ui-card{background:var(--navy-card);border:1px solid var(--navy-line);border-radius:18px;padding:18px}
.lesson-list{min-width:210px}
.lesson-row{
  display:grid;grid-template-columns:1fr 1.4fr auto;align-items:center;gap:10px;
  padding:9px 12px;border-radius:10px;font-family:"JetBrains Mono",monospace;
}
.lesson-row .ch{font-weight:700;color:var(--white)}
.lesson-row .mc{color:var(--teal);letter-spacing:.1em}
.lesson-row .done{color:var(--green)}
.lesson-row .now{color:var(--teal)}
.lesson-row .lock{opacity:.5}
.lesson-row.active{background:rgba(39,211,232,.1)}
.lesson-row.locked{opacity:.55}
.current-char{display:flex;flex-direction:column;align-items:center;justify-content:center;min-width:190px;gap:6px}
.big-char{font-size:5rem;font-weight:800;line-height:1;color:var(--white)}
.big-morse{font-family:"JetBrains Mono",monospace;color:var(--teal);font-size:1.6rem;letter-spacing:.2em}
.wpm-row{display:flex;align-items:center;gap:10px;margin-top:18px;font-size:.82rem;color:var(--muted);font-family:"JetBrains Mono",monospace}
.bars{display:flex;gap:3px}
.bars i{width:9px;height:14px;border-radius:2px;background:var(--teal)}
.bars i.off{background:var(--navy-line)}
.progress-count{font-family:"JetBrains Mono",monospace;color:var(--muted);font-size:.9rem;margin-top:8px}

/* modes */
.modes{grid-template-columns:repeat(3,1fr)}
.mode{
  display:flex;gap:14px;align-items:flex-start;
  background:var(--navy-card);border:1px solid var(--navy-line);
  border-radius:14px;padding:18px 20px;
}
.mode:hover{border-color:var(--teal)}
.mode-mc{
  font-family:"JetBrains Mono",monospace;color:var(--teal);
  font-size:1rem;letter-spacing:.1em;min-width:46px;
  padding-top:3px;flex-shrink:0;
}
.mode h4{font-size:1.05rem;margin-bottom:3px}
.mode p{color:var(--muted);font-size:.92rem;line-height:1.5}

/* about */
.about{text-align:center;display:flex;flex-direction:column;align-items:center}
.about-mark{height:104px;width:auto;margin-bottom:24px;filter:drop-shadow(0 8px 26px rgba(39,211,232,.22))}
.about .section-sub{font-size:1.12rem;margin-bottom:8px}
.about .hero-actions{margin-top:28px}

/* footer */
.footer{
  border-top:1px solid var(--navy-line);
  background:#050F1F;
  padding:48px 24px;
  display:flex;flex-direction:column;align-items:center;gap:18px;text-align:center;
}
.footer-brand{display:flex;flex-direction:column;align-items:center;gap:12px}
.footer-logo{height:96px;width:auto;display:block}
.footer-tag{font-family:"JetBrains Mono",monospace;color:var(--muted);font-size:.9rem}
.badges{display:flex;gap:10px;flex-wrap:wrap;justify-content:center}
.badge{
  display:inline-flex;font-family:"JetBrains Mono",monospace;font-size:.78rem;
  border-radius:6px;overflow:hidden;border:1px solid var(--navy-line);
}
.badge i{background:#0C2342;color:var(--muted);padding:4px 9px;font-style:normal}
.badge b{padding:4px 9px;color:#06121F;font-weight:700}
.badge .green{background:var(--green)}
.badge .amber{background:var(--amber)}
.badge .teal{background:var(--teal)}
.footer-repo a{font-family:"JetBrains Mono",monospace;color:var(--teal);font-size:.92rem}
.footer-repo a:hover{text-decoration:underline}
.footer-fine{color:var(--muted);font-size:.85rem}

/* responsive */
@media(max-width:860px){
  .hero{grid-template-columns:1fr;text-align:center;padding-top:56px}
  .hero-actions,.eyebrow{justify-content:center}
  .lede{margin-left:auto;margin-right:auto}
  .hero-art{order:-1}
  .features,.modes{grid-template-columns:1fr 1fr}
  .showcase{grid-template-columns:1fr}
  .showcase-text{text-align:center}
  .checklist{align-items:flex-start;max-width:420px;margin-left:auto;margin-right:auto}
}
@media(max-width:600px){
  .nav-links{display:none}
  .features,.modes{grid-template-columns:1fr}
  .section{padding:60px 20px}
  .showcase-ui{flex-direction:column;align-items:center}
}
@media(prefers-reduced-motion:reduce){
  .waveform span{animation:none}
  *{scroll-behavior:auto}
}