:root{
 --p-900:#091014; --p-800:#122028; --p-700:#1A2F3B; --p-600:#233F4F;
 --p-400:#567282; --p-300:#8095A1; --p-100:#D5DCE0; --white:#fff;
 --accent:#3DE0C5; --present:#E0B33D; --absent:#233F4F; --wrong:#E0703D; --ink:#091014;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,sans-serif;background:var(--p-900);color:var(--p-100);line-height:1.6;-webkit-font-smoothing:antialiased;min-height:100vh;display:flex;flex-direction:column}
a{color:var(--accent)}
.wrap{width:100%;max-width:960px;margin:0 auto;padding:0 1.25rem}
main{flex:1 0 auto;padding:2.5rem 0 4rem}
h1,h2,h3{color:var(--white);line-height:1.15;letter-spacing:-.02em}
.eyebrow{color:var(--accent);font-weight:600;font-size:.8rem;letter-spacing:.12em;text-transform:uppercase}
/* nav */
.nav{background:rgba(9,16,20,.9);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-bottom:1px solid rgba(255,255,255,.07);position:sticky;top:0;z-index:100}
.nav-inner{display:flex;align-items:center;justify-content:space-between;padding:.8rem 1.25rem;max-width:1100px;margin:0 auto}
.logo img{height:30px;display:block;filter:brightness(0) invert(1)}
.btn{display:inline-flex;align-items:center;gap:.5rem;padding:.7rem 1.4rem;border-radius:8px;font-weight:600;font-size:.95rem;text-decoration:none;border:1px solid transparent;cursor:pointer;transition:transform .2s,background .2s;white-space:nowrap}
.btn-primary{background:var(--accent);color:var(--ink)!important}
.btn-primary:hover{background:#5fe9d3;transform:translateY(-2px)}
.btn-ghost{background:transparent;color:var(--white)!important;border-color:rgba(255,255,255,.25)}
.btn-ghost:hover{border-color:var(--white)}
/* footer */
.foot{flex-shrink:0;border-top:1px solid rgba(255,255,255,.07);padding:1.5rem 0;color:var(--p-300);font-size:.85rem;text-align:center}
.foot a{color:var(--p-100)}
.foot .links{margin-top:.4rem;color:var(--p-300)}
/* hub */
.hero-head{text-align:center;max-width:720px;margin:0 auto 2.5rem}
.hero-head h1{font-size:clamp(1.9rem,4.5vw,2.8rem);margin:.6rem 0 1rem}
.hero-head p{color:var(--p-100);font-size:1.05rem}
.pillrow{display:flex;gap:.5rem;flex-wrap:wrap;justify-content:center;margin-top:1.25rem}
.pill{background:var(--p-800);border:1px solid rgba(255,255,255,.08);border-radius:999px;padding:.35rem .9rem;font-size:.82rem;color:var(--p-100)}
.cards{display:grid;grid-template-columns:repeat(2,1fr);gap:1.5rem}
.card{background:var(--p-800);border:1px solid rgba(255,255,255,.08);border-radius:16px;padding:1.75rem;text-decoration:none;color:inherit;display:flex;flex-direction:column;transition:transform .2s,border-color .2s}
.card:hover{transform:translateY(-4px);border-color:var(--accent)}
.card .tag{color:var(--accent);font-size:.75rem;font-weight:600;letter-spacing:.1em;text-transform:uppercase}
.card h2{font-size:1.4rem;margin:.5rem 0 .6rem}
.card p{color:var(--p-100);font-size:.95rem;flex:1}
.card .go{margin-top:1rem;color:var(--accent);font-weight:600}
.badge-week{display:inline-block;background:rgba(61,224,197,.12);color:var(--accent);border:1px solid rgba(61,224,197,.3);padding:.2rem .6rem;border-radius:999px;font-size:.72rem;font-weight:600;letter-spacing:.04em;margin:.75rem 0}
/* panel + back */
.panel{background:var(--p-800);border:1px solid rgba(255,255,255,.08);border-radius:16px;padding:1.5rem;max-width:640px;margin:1.25rem auto 0}
.back{display:inline-flex;align-items:center;gap:.4rem;color:var(--p-300);text-decoration:none;font-size:.9rem}
.back:hover{color:var(--white)}
.center{text-align:center}
/* question */
.q-text{color:var(--white);font-size:1.15rem;font-weight:600;margin:.5rem 0 1.25rem}
.choices{display:flex;flex-direction:column;gap:.7rem}
.choice{display:flex;gap:.75rem;align-items:center;text-align:left;background:var(--p-700);border:1px solid rgba(255,255,255,.1);color:var(--p-100);border-radius:10px;padding:.85rem 1rem;font-size:1rem;cursor:pointer;transition:border-color .15s,background .15s;font-family:inherit;width:100%}
.choice:hover:not(:disabled){border-color:var(--accent)}
.choice .kbd{flex-shrink:0;width:1.7rem;height:1.7rem;border-radius:6px;background:var(--p-600);display:grid;place-items:center;font-weight:700;font-size:.85rem;color:var(--white)}
.choice.correct{border-color:var(--accent);background:rgba(61,224,197,.12)}
.choice.correct .kbd{background:var(--accent);color:var(--ink)}
.choice.wrong{border-color:var(--wrong);background:rgba(224,112,61,.12)}
.choice.wrong .kbd{background:var(--wrong);color:var(--white)}
.choice:disabled{cursor:default}
.choice:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.ans-mark{margin-left:auto;font-weight:700;font-size:1.15rem}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.rationale{margin-top:1.25rem;padding:1rem;border-radius:10px;background:var(--p-900);border:1px solid rgba(255,255,255,.08);font-size:.95rem;color:var(--p-100);display:none}
.rationale.show{display:block}
.rationale strong{color:var(--accent)}
.cta-row{margin-top:1.5rem;display:flex;gap:.75rem;flex-wrap:wrap}
/* neudle */
.board{display:grid;grid-template-rows:repeat(6,1fr);gap:.4rem;width:min(330px,86vw);margin:1.25rem auto}
.brow{display:grid;grid-template-columns:repeat(5,1fr);gap:.4rem}
.tile{aspect-ratio:1;display:grid;place-items:center;font-size:1.6rem;font-weight:700;text-transform:uppercase;color:var(--white);background:var(--p-800);border:2px solid var(--p-600);border-radius:6px}
.tile.filled{border-color:var(--p-400)}
.tile.correct{background:var(--accent);border-color:var(--accent);color:var(--ink)}
.tile.present{background:var(--present);border-color:var(--present);color:var(--ink)}
.tile.absent{background:var(--absent);border-color:var(--absent);color:var(--p-200)}
.keyboard{max-width:500px;margin:1rem auto 0;display:flex;flex-direction:column;gap:.4rem}
.krow{display:flex;gap:.35rem;justify-content:center}
.key{flex:1;min-width:0;height:3.2rem;border-radius:6px;background:var(--p-600);color:var(--white);border:none;font-weight:600;font-size:1rem;cursor:pointer;font-family:inherit;text-transform:uppercase}
.key.wide{flex:1.5;font-size:.8rem}
.key:hover{background:var(--p-400)}
.key.correct{background:var(--accent);color:var(--ink)}
.key.present{background:var(--present);color:var(--ink)}
.key.absent{background:var(--absent);color:var(--p-200)}
.msg{text-align:center;min-height:1.4rem;margin-top:.6rem;color:var(--accent);font-weight:600;font-size:.95rem}
.reveal-box{margin:1rem auto 0;max-width:520px;padding:1.1rem;border-radius:12px;background:var(--p-800);border:1px solid rgba(255,255,255,.08);display:none}
.reveal-box.show{display:block}
.reveal-box .cat{font-size:.72rem;text-transform:uppercase;letter-spacing:.1em;color:var(--p-300)}
.reveal-box .word{font-size:1.5rem;font-weight:700;color:var(--accent);letter-spacing:.06em}
@media(max-width:640px){
 .cards{grid-template-columns:1fr}
 .key{height:2.9rem;font-size:.9rem}
 .tile{font-size:1.3rem}
 main{padding:1.5rem 0 3rem}
}