:root{
  --bg:#0a0e1a;
  --bg2:#11172a;
  --accent:#6ee7ff;
  --accent2:#a78bfa;
  --accent3:#f472b6;
  --text:#e6edf7;
  --muted:#94a3b8;
  --card:#151c33;
  --border:#24304d;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:'Segoe UI',system-ui,-apple-system,sans-serif;
  background:var(--bg);
  color:var(--text);
  line-height:1.65;
}

/* DNA sequence signature strip — appears under hero and between key sections */
.seq-strip{
  font-family:'Courier New',monospace;
  font-size:.75rem;letter-spacing:4px;
  color:var(--border);
  white-space:nowrap;overflow:hidden;
  padding:10px 0;
  user-select:none;
}
.seq-strip span{color:var(--accent);opacity:.5}

/* HERO */
.hero{
  min-height:60vh;
  display:flex;flex-direction:column;justify-content:center;align-items:center;
  text-align:center;padding:3rem 2rem 2rem;
  background:
    radial-gradient(circle at 20% 30%, rgba(110,231,255,.15), transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(167,139,250,.15), transparent 50%),
    linear-gradient(180deg,#0a0e1a 0%,#0f1528 100%);
}
.hero .eyebrow{
  color:var(--accent);font-size:.8rem;letter-spacing:3px;text-transform:uppercase;
  margin-bottom:14px;font-weight:600;
}
.hero h1{
  font-size:clamp(2rem,5vw,3.4rem);
  background:linear-gradient(90deg,var(--accent),var(--accent2),var(--accent3));
  -webkit-background-clip:text;background-clip:text;color:transparent;
  margin-bottom:1rem;font-weight:800;letter-spacing:-1px;
}
.hero p{max-width:720px;font-size:1.1rem;color:var(--muted)}
.hero .cta{
  display:inline-block;margin-top:1.6rem;
  padding:14px 32px;border-radius:50px;
  background:linear-gradient(90deg,var(--accent),var(--accent2));
  color:#0a0e1a;font-weight:700;text-decoration:none;
  box-shadow:0 10px 30px rgba(110,231,255,.3);
}

/* NAV */
nav.topnav{
  position:sticky;top:0;z-index:100;
  background:rgba(10,14,26,.9);
  -webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);
  border-bottom:1px solid var(--border);
  padding:14px 20px;
  display:flex;gap:6px;align-items:center;flex-wrap:wrap;
}
nav.topnav .brand{
  color:var(--text);font-weight:800;font-size:.95rem;text-decoration:none;
  margin-right:16px;white-space:nowrap;
}
nav.topnav .brand span{color:var(--accent)}
nav.topnav a.navlink{
  color:var(--muted);text-decoration:none;
  padding:7px 13px;border-radius:20px;
  font-size:.82rem;white-space:nowrap;
  transition:all .2s;border:1px solid transparent;
}
nav.topnav a.navlink:hover{color:var(--accent);border-color:var(--border)}
nav.topnav a.navlink.current{color:var(--accent);border-color:var(--accent)}

/* MÓDULO TRILHA — sequência pedagógica real, por isso numerada */
.trail{
  max-width:900px;margin:30px auto 10px;padding:0 20px;
  display:flex;gap:8px;flex-wrap:wrap;justify-content:center;
}
.trail a{
  width:34px;height:34px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;
  font-size:.75rem;font-weight:700;text-decoration:none;
  background:var(--card);border:1px solid var(--border);color:var(--muted);
}
.trail a.current{background:linear-gradient(90deg,var(--accent),var(--accent2));color:#0a0e1a;border:none}
.trail a:hover{border-color:var(--accent)}

/* SECTIONS */
main{max-width:900px;margin:0 auto;padding:20px 24px 60px}
.module-label{
  display:inline-block;color:var(--accent);font-size:.8rem;font-weight:700;
  letter-spacing:2px;text-transform:uppercase;margin-bottom:8px;
}
h2{
  font-size:1.9rem;margin:40px 0 14px;
  background:linear-gradient(90deg,var(--accent),var(--accent3));
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
h2:first-of-type{margin-top:10px}
h3{font-size:1.25rem;color:var(--accent);margin:24px 0 10px}
p{color:var(--text);margin-bottom:14px;font-size:1rem}
p.muted{color:var(--muted)}
ul,ol{margin:0 0 16px 22px;color:var(--text)}
li{margin-bottom:8px}
strong{color:var(--accent)}
em{color:var(--accent2);font-style:italic}

/* CALLOUT — chamada visual */
.callout{
  background:var(--card);border-left:3px solid var(--accent);
  border-radius:10px;padding:18px 22px;margin:22px 0;
  font-family:'Courier New',monospace;font-size:.95rem;color:var(--accent);
}
.callout.pink{border-left-color:var(--accent3);color:var(--accent3)}

/* WARNING BOX */
.warning{
  background:rgba(244,114,182,.08);border:1px solid rgba(244,114,182,.35);
  border-radius:12px;padding:20px 22px;margin:24px 0;
}
.warning h4{color:var(--accent3);margin-bottom:8px;font-size:1rem}
.warning p{color:var(--muted);font-size:.92rem;margin-bottom:0}

/* CODE / SEQUENCE EXAMPLE */
.dna-example{
  background:var(--bg2);border:1px solid var(--border);border-radius:10px;
  padding:16px 20px;margin:16px 0;font-family:'Courier New',monospace;
  font-size:1.05rem;letter-spacing:3px;
}
.dna-example .diff{color:var(--accent3);font-weight:700}
.dna-example .label{display:block;font-family:'Segoe UI',sans-serif;font-size:.75rem;
  letter-spacing:0;color:var(--muted);margin-bottom:6px}

/* CARDS / GRID */
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:18px;margin:20px 0}
.card{
  background:var(--card);border:1px solid var(--border);
  border-radius:14px;padding:20px;transition:transform .2s,border-color .2s;
}
.card:hover{transform:translateY(-3px);border-color:var(--accent2)}
.card h4{color:var(--accent);margin-bottom:8px;font-size:1.05rem}
.card p{color:var(--muted);font-size:.9rem;margin-bottom:0}

/* LAUDO EXAMPLE TABLE */
.laudo-box{
  background:var(--card);border:1px solid var(--border);border-radius:14px;
  padding:22px;margin:20px 0;
}
.laudo-row{display:flex;gap:12px;padding:10px 0;border-bottom:1px dashed var(--border);font-size:.92rem}
.laudo-row:last-child{border:none}
.laudo-row .k{color:var(--muted);min-width:140px}
.laudo-row .v{color:var(--accent)}

/* ACCORDION (FAQ) */
.accordion{margin:20px 0}
.acc-item{background:var(--card);border:1px solid var(--border);border-radius:12px;margin-bottom:10px;overflow:hidden}
.acc-q{
  width:100%;text-align:left;padding:16px 20px;background:transparent;border:none;
  color:var(--text);font-size:.95rem;font-weight:600;cursor:pointer;
  display:flex;justify-content:space-between;align-items:center;
}
.acc-q .plus{color:var(--accent);font-size:1.2rem;transition:transform .2s}
.acc-item.open .acc-q .plus{transform:rotate(45deg)}
.acc-a{max-height:0;overflow:hidden;transition:max-height .3s ease}
.acc-a p{padding:0 20px 18px;color:var(--muted);font-size:.9rem;margin:0}
.acc-item.open .acc-a{max-height:400px}

/* MINI QUIZ (homo/heterozigoto) */
.mini-quiz{background:var(--card);border:1px solid var(--border);border-radius:14px;padding:24px;margin:24px 0}
.mini-quiz .qopts{display:flex;gap:10px;flex-wrap:wrap;margin-top:14px}
.mini-quiz button.opt{
  padding:10px 18px;border-radius:10px;background:var(--bg2);border:1px solid var(--border);
  color:var(--text);cursor:pointer;font-family:'Courier New',monospace;font-size:1rem;letter-spacing:2px;
}
.mini-quiz button.opt:hover{border-color:var(--accent)}
.mini-quiz .feedback{margin-top:14px;font-size:.9rem;color:var(--muted);display:none}
.mini-quiz .feedback.show{display:block}
.mini-quiz .feedback.correct{color:var(--accent)}
.mini-quiz .feedback.wrong{color:var(--accent3)}

/* LAUDO READER TOOL */
.reader-tool{background:var(--card);border:1px solid var(--border);border-radius:16px;padding:24px;margin:24px 0}
.reader-tool select,.reader-tool input{
  background:var(--bg2);border:1px solid var(--border);color:var(--text);
  padding:10px 14px;border-radius:8px;font-size:.9rem;margin-right:10px;margin-bottom:10px;
  font-family:'Courier New',monospace;
}
.reader-output{margin-top:14px;padding:16px;background:var(--bg2);border-radius:10px;border-left:3px solid var(--accent);display:none}
.reader-output.show{display:block}
.reader-output p{margin-bottom:6px;font-size:.9rem;color:var(--muted)}
.reader-output strong{color:var(--accent)}

/* PAGE PAGINATION (prev/next module) */
.pager{display:flex;justify-content:space-between;margin-top:50px;gap:16px;flex-wrap:wrap}
.pager a{
  flex:1;min-width:220px;padding:16px 20px;border-radius:12px;
  background:var(--card);border:1px solid var(--border);text-decoration:none;
  color:var(--text);transition:border-color .2s;
}
.pager a:hover{border-color:var(--accent)}
.pager a .dir{color:var(--muted);font-size:.75rem;text-transform:uppercase;letter-spacing:1px;display:block;margin-bottom:4px}
.pager a.next{text-align:right}

/* AUTHOR BOX */
.author-box{
  max-width:700px;margin:50px auto 0;text-align:center;
}
.author-box .card{margin:0}

footer{
  text-align:center;padding:40px 20px;
  border-top:1px solid var(--border);
  color:var(--muted);font-size:.9rem;
  background:var(--bg2);margin-top:40px;
}
footer p.small{font-size:.78rem;max-width:600px;margin:14px auto 0}

/* FIXED CTA BAR */
body.has-fixed-cta{padding-bottom:68px}
.fixed-cta{
  position:fixed;bottom:0;left:0;right:0;z-index:99;
  background:rgba(10,14,26,.92);
  -webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);
  border-top:1px solid var(--border);
}
.fixed-cta-inner{
  max-width:900px;margin:0 auto;
  padding:12px 20px;
  display:flex;align-items:center;justify-content:space-between;gap:16px;
}
.fixed-cta-text{
  font-size:.88rem;line-height:1.45;margin:0;color:var(--text);
}
.fixed-cta-text strong{color:var(--accent)}
.fixed-cta-sub{
  display:block;margin-top:4px;
  font-size:.78rem;color:var(--muted);
}
.fixed-cta-btn{
  flex-shrink:0;
  padding:12px 24px;border-radius:50px;
  background:linear-gradient(90deg,var(--accent),var(--accent2));
  color:#0a0e1a;font-weight:700;text-decoration:none;
  box-shadow:0 6px 20px rgba(110,231,255,.25);
  font-size:.85rem;white-space:nowrap;
  transition:box-shadow .2s;
}
.fixed-cta-btn:hover{box-shadow:0 8px 28px rgba(110,231,255,.4)}

@media(max-width:640px){
  nav.topnav{overflow-x:auto}
  body.has-fixed-cta{padding-bottom:120px}
  .fixed-cta-inner{
    flex-direction:column;text-align:center;
    padding:14px 16px;
  }
  .fixed-cta-btn{width:100%;text-align:center}
}