:root{
  --bg:#f4f5fb; --paper:#ffffff; --ink:#141621; --ink-2:#565d70; --ink-3:#98a0b3;
  --line:rgba(20,22,33,.09); --accent:#5b57f0; --accent-2:#ff7a3d; --good:#18b06b;
  --shadow:0 14px 40px rgba(40,40,90,.10);
  --disp:"Unbounded","Segoe UI",system-ui,sans-serif;
  --sans:"Manrope",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,sans-serif;
  --eo:cubic-bezier(.23,1,.32,1);
}
@media (prefers-color-scheme:dark){:root{
  --bg:#0f1017; --paper:#181a24; --ink:#eef0f7; --ink-2:#aab1c4; --ink-3:#6c7488;
  --line:rgba(255,255,255,.10); --shadow:0 14px 40px rgba(0,0,0,.5);
}}
*{box-sizing:border-box}
html{scroll-behavior:smooth}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important;animation:none!important}}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--sans);line-height:1.6;-webkit-font-smoothing:antialiased;overflow-x:hidden}
img{max-width:100%;display:block}a{color:inherit;text-decoration:none}
.wrap{max-width:1120px;margin:0 auto;padding:0 22px}
::selection{background:var(--accent);color:#fff}

/* nav */
nav{position:sticky;top:0;z-index:60;background:color-mix(in srgb,var(--bg) 84%,transparent);backdrop-filter:saturate(160%) blur(16px);-webkit-backdrop-filter:saturate(160%) blur(16px);border-bottom:1px solid var(--line)}
.nav-in{max-width:1120px;margin:0 auto;padding:0 22px;height:62px;display:flex;align-items:center;gap:24px}
.logo{font-family:var(--disp);font-weight:800;font-size:23px;letter-spacing:-.02em;display:flex;align-items:center;gap:9px}
.logo .qm{width:30px;height:30px;flex:0 0 auto;border-radius:9px;background:linear-gradient(135deg,var(--accent),var(--accent-2));color:#fff;display:grid;place-items:center;font-size:19px;font-weight:800;box-shadow:0 6px 16px rgba(91,87,240,.35)}
.nav-links{margin-left:auto;display:flex;gap:20px;font-size:14px;font-weight:600;color:var(--ink-2)}
.nav-links a{transition:color .2s;white-space:nowrap}.nav-links a.on{color:var(--accent)}
@media(hover:hover){.nav-links a:hover{color:var(--accent)}}
@media(max-width:720px){.nav-in{gap:12px;padding:0 14px}.nav-links{gap:14px;font-size:13px;overflow-x:auto;white-space:nowrap;scrollbar-width:none}.nav-links::-webkit-scrollbar{display:none}}

/* hero */
header.hero{padding:64px 0 26px;text-align:center}
.eyebrow{font-size:12.5px;font-weight:700;letter-spacing:.2em;text-transform:uppercase;color:var(--accent);margin:0 0 18px}
h1{font-family:var(--disp);font-weight:800;font-size:clamp(38px,7vw,74px);line-height:1.02;letter-spacing:-.03em;margin:0 auto;max-width:16ch}
h1 .hl{background:linear-gradient(120deg,var(--accent),var(--accent-2));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.dek{color:var(--ink-2);font-size:clamp(16px,2vw,20px);max-width:52ch;margin:22px auto 0}
.crumbs{font-size:12.5px;letter-spacing:.04em;color:var(--ink-3);margin-bottom:14px}.crumbs a{color:var(--ink-2)}
.page-head{padding:48px 0 12px}.page-head h1{margin:0;text-align:left;font-size:clamp(32px,5.5vw,58px)}
.page-head .dek{margin:18px 0 0;text-align:left}

/* category tiles */
section{padding:44px 0}
.sec-h{display:flex;align-items:baseline;justify-content:space-between;gap:16px;margin-bottom:22px;border-top:1px solid var(--line);padding-top:20px;flex-wrap:wrap}
.sec-h h2{font-family:var(--disp);font-weight:700;font-size:clamp(22px,3.2vw,32px);margin:0;letter-spacing:-.02em}
.sec-h .k{font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:var(--ink-3);font-weight:700}
.cats{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
@media(max-width:760px){.cats{grid-template-columns:1fr}}
.cat{background:var(--paper);border:1px solid var(--line);border-radius:18px;padding:24px;display:block;transition:transform .35s var(--eo),box-shadow .35s;box-shadow:var(--shadow)}
@media(hover:hover){.cat:hover{transform:translateY(-5px);box-shadow:0 22px 50px rgba(40,40,90,.16)}}
.cat .ico{font-size:30px}.cat h3{font-family:var(--disp);font-weight:700;font-size:21px;margin:12px 0 6px}
.cat p{margin:0;color:var(--ink-2);font-size:14.5px}
.cat .go{margin-top:14px;font-weight:700;font-size:13px;color:var(--accent)}

/* reveal cards */
.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
@media(max-width:860px){.grid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.grid{grid-template-columns:1fr}}
.qcard{background:var(--paper);border:1px solid var(--line);border-radius:18px;overflow:hidden;box-shadow:var(--shadow);cursor:pointer;transition:transform .3s var(--eo)}
.qcard:active{transform:scale(.99)}
.qcard .ph{aspect-ratio:4/3;position:relative;overflow:hidden;background:#0c0d12}
.qcard .ph img{width:100%;height:100%;object-fit:cover;transition:transform .6s var(--eo),filter .5s}
.qcard .badge{position:absolute;left:12px;top:12px;z-index:2;display:flex;align-items:center;gap:7px;background:rgba(12,13,18,.62);backdrop-filter:blur(6px);color:#fff;font-weight:700;font-size:13px;padding:6px 12px;border-radius:980px}
.qcard .badge .d{width:20px;height:20px;border-radius:50%;background:linear-gradient(135deg,var(--accent),var(--accent-2));display:grid;place-items:center;font-size:13px}
.qcard.shown .badge .d{background:var(--good)}
.qcard .bd{padding:16px 18px 18px}
.qcard .q{font-family:var(--disp);font-weight:700;font-size:18px;letter-spacing:-.01em;margin:0}
.qcard .hint{color:var(--ink-2);font-size:14px;margin:6px 0 0}
.qcard .ans{max-height:0;opacity:0;overflow:hidden;transition:max-height .5s var(--eo),opacity .4s,margin .4s}
.qcard.shown .ans{max-height:360px;opacity:1;margin-top:14px}
.qcard .ans .name{font-family:var(--disp);font-weight:800;font-size:20px;color:var(--accent)}
.qcard .ans .yr{display:inline-block;font-size:11px;font-weight:700;letter-spacing:.06em;color:var(--ink-3);border:1px solid var(--line);border-radius:980px;padding:2px 9px;margin-left:8px;vertical-align:middle}
.qcard .ans p{margin:8px 0 0;color:var(--ink-2);font-size:14.5px;line-height:1.6}
.qcard .tap{margin-top:12px;font-size:12.5px;font-weight:700;color:var(--accent);letter-spacing:.02em}
.qcard.shown .tap{color:var(--ink-3)}

/* featured big reveal */
.feat{background:var(--paper);border:1px solid var(--line);border-radius:24px;overflow:hidden;box-shadow:var(--shadow);display:grid;grid-template-columns:1.1fr 1fr;cursor:pointer}
@media(max-width:760px){.feat{grid-template-columns:1fr}}
.feat .ph{position:relative;background:#0c0d12;min-height:280px}
.feat .ph img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.feat .bd{padding:34px 32px;display:flex;flex-direction:column;justify-content:center}
.feat .tag{font-size:12px;font-weight:700;letter-spacing:.16em;text-transform:uppercase;color:var(--accent-2)}
.feat h2{font-family:var(--disp);font-weight:800;font-size:clamp(24px,3.4vw,34px);margin:10px 0 8px;letter-spacing:-.02em}
.feat .hint{color:var(--ink-2);font-size:16px;margin:0}
.feat .ans{max-height:0;opacity:0;overflow:hidden;transition:.5s var(--eo)}
.feat.shown .ans{max-height:300px;opacity:1;margin-top:14px}
.feat .ans .name{font-family:var(--disp);font-weight:800;font-size:22px;color:var(--accent)}
.feat .ans p{color:var(--ink-2);font-size:15px;margin:8px 0 0}
.feat .btn{margin-top:18px;align-self:flex-start}

.btn{appearance:none;border:0;cursor:pointer;font:inherit;font-weight:700;font-size:14px;padding:12px 22px;border-radius:980px;background:linear-gradient(120deg,var(--accent),var(--accent-2));color:#fff;box-shadow:0 10px 26px rgba(91,87,240,.32);transition:transform .12s var(--eo)}
.btn:active{transform:scale(.95)}
.btn.ghost{background:transparent;color:var(--ink);border:1px solid var(--line);box-shadow:none}

/* slang accordion */
.slang{display:grid;grid-template-columns:1fr 1fr;gap:12px}
@media(max-width:680px){.slang{grid-template-columns:1fr}}
.term{background:var(--paper);border:1px solid var(--line);border-radius:14px;padding:16px 18px;cursor:pointer;transition:border-color .25s}
@media(hover:hover){.term:hover{border-color:var(--accent)}}
.term .w{font-family:var(--disp);font-weight:700;font-size:18px;display:flex;justify-content:space-between;align-items:center}
.term .w .pl{color:var(--accent);font-size:22px;transition:transform .3s var(--eo)}
.term.open .w .pl{transform:rotate(45deg)}
.term .def{max-height:0;opacity:0;overflow:hidden;transition:.4s var(--eo);color:var(--ink-2);font-size:14.5px}
.term.open .def{max-height:140px;opacity:1;margin-top:8px}

/* quiz */
.quiz{max-width:640px;margin:0 auto;background:var(--paper);border:1px solid var(--line);border-radius:22px;box-shadow:var(--shadow);overflow:hidden}
.quiz .qph{aspect-ratio:16/10;background:#0c0d12;position:relative}
.quiz .qph img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.quiz .qbar{height:6px;background:var(--line)}.quiz .qbar i{display:block;height:100%;background:linear-gradient(90deg,var(--accent),var(--accent-2));width:0;transition:width .4s var(--eo)}
.quiz .qbd{padding:24px 26px 28px}
.quiz .qh{font-family:var(--disp);font-weight:700;font-size:22px;margin:0 0 4px}
.quiz .qc{color:var(--ink-3);font-size:13px;font-weight:700;letter-spacing:.04em}
.opts{display:grid;gap:10px;margin-top:16px}
.opt{appearance:none;text-align:left;border:1px solid var(--line);background:transparent;color:var(--ink);font:inherit;font-size:15.5px;font-weight:600;padding:14px 16px;border-radius:12px;cursor:pointer;transition:.18s var(--eo)}
@media(hover:hover){.opt:hover{border-color:var(--accent)}}
.opt.correct{background:color-mix(in srgb,var(--good) 16%,transparent);border-color:var(--good);color:var(--good)}
.opt.wrong{background:color-mix(in srgb,#ff4d4d 14%,transparent);border-color:#ff5a5a;color:#ff5a5a}
.opt:disabled{cursor:default}
.quiz .nextrow{margin-top:16px;display:flex;justify-content:space-between;align-items:center;min-height:44px}
.quiz .fb{font-weight:700;font-size:14px}
.quiz .res{text-align:center;padding:44px 26px}
.quiz .res .big{font-family:var(--disp);font-size:56px;font-weight:800;background:linear-gradient(120deg,var(--accent),var(--accent-2));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}

/* prose / about */
.prose{max-width:680px}.prose h2{font-family:var(--disp);font-size:26px;margin:34px 0 10px}
.prose p{font-size:16.5px;color:var(--ink-2);margin:0 0 16px}.prose p strong{color:var(--ink)}
.qa{border-top:1px solid var(--line);padding:18px 0}.qa b{font-family:var(--disp);font-size:17px}.qa p{margin:8px 0 0;color:var(--ink-2)}

footer{border-top:1px solid var(--line);padding:40px 0 60px;color:var(--ink-3);font-size:13.5px;margin-top:34px}
.foot-in{display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;align-items:center}
.foot-links{display:flex;gap:20px}.foot-links a{color:var(--ink-2)}
@media(max-width:640px){.foot-in{flex-direction:column;align-items:flex-start;gap:12px}}
/* --- mobile hardening --- */
html{overflow-x:hidden}
@media(max-width:600px){
  h1{font-size:clamp(30px,8vw,58px)}
  .page-head h1{font-size:clamp(27px,7.5vw,46px)}
  .dek,.prose{max-width:100%}
  .sec-h{flex-direction:column;align-items:flex-start;gap:4px}
  .feat{grid-template-columns:1fr}
}