:root{
  --space-950:#070b1d;--space-900:#0b1230;--space-800:#121a40;--space-700:#1a2456;
  --graphite-900:#141a2c;--graphite-800:#1b2238;--graphite-700:#262f4c;
  --ink:#0f1730;--ink-2:#3b4560;--ink-3:#5a6480;
  --paper:#f4f6fc;--paper-2:#e9edf8;--white:#fff;--line:#dbe1f1;
  --purple:#5b3fe0;--purple-2:#7c5cff;--purple-3:#b9a8ff;
  --cyan:#0e7490;--cyan-2:#22d3ee;
  --lime:#a6e22e;--lime-2:#c6f26a;--lime-ink:#3f6212;
  --brand:#0d7a58;
  --ok:#0f7a3e;--ok-bg:#e3f7ea;--bad:#b4231f;--bad-bg:#fdeaea;
  --on-dark:#e9edff;--on-dark-2:#b3bde3;
  --radius:16px;--radius-sm:10px;
  --shadow:0 1px 2px rgba(15,23,60,.06),0 10px 28px -14px rgba(15,23,60,.28);
  --shadow-lg:0 2px 4px rgba(7,11,29,.2),0 24px 60px -24px rgba(7,11,29,.6);
  --font:ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  --mono:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --focus:#7c5cff;
}
*,*::before,*::after{box-sizing:border-box}
[hidden]{display:none!important}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:96px}
body{margin:0;font-family:var(--font);font-size:1.0625rem;line-height:1.65;color:var(--ink);background:var(--paper);min-height:100vh;display:flex;flex-direction:column}
main{flex:1}
img,svg{max-width:100%;height:auto}
img{display:block}
a{color:var(--purple);text-underline-offset:.2em}
a:hover{color:#3d24b8}
h1,h2,h3,h4{line-height:1.15;letter-spacing:-.02em;margin:0 0 .5em;font-weight:800;color:var(--ink)}
h1{font-size:clamp(2rem,4.2vw,3.1rem)}
h2{font-size:clamp(1.5rem,2.6vw,2.05rem)}
h3{font-size:1.25rem}
p{margin:0 0 1em}
ul,ol{margin:0 0 1em;padding-left:1.3em}
:focus-visible{outline:3px solid var(--focus);outline-offset:3px;border-radius:4px}
.on-dark :focus-visible,.site-footer :focus-visible{outline-color:var(--cyan-2)}
.visually-hidden{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.skip-link{position:absolute;left:12px;top:-60px;background:var(--space-900);color:#fff;padding:.7rem 1rem;border-radius:8px;z-index:100;font-weight:700}
.skip-link:focus{top:12px}
.container{width:min(1140px,100% - 32px);margin-inline:auto}
.narrow{width:min(760px,100% - 32px);margin-inline:auto}
.icon{width:1.25em;height:1.25em;flex:none;vertical-align:-.25em}

/* Header */
.site-header{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:50}
.header-inner{display:flex;align-items:center;gap:1rem;min-height:68px}
.brand{display:flex;align-items:center;flex:none}
.brand img{width:168px;height:40px}
.nav{margin-left:auto;display:flex;align-items:center;gap:.25rem}
.nav a{display:inline-flex;align-items:center;gap:.4rem;padding:.55rem .8rem;border-radius:10px;color:var(--ink);text-decoration:none;font-weight:650;font-size:.98rem}
.nav a:hover{background:var(--paper-2);color:var(--ink)}
.nav a[aria-current="page"]{color:var(--purple);background:#efeaff}
.nav .nav-cta{background:var(--space-900);color:#fff}
.nav .nav-cta:hover{background:var(--space-700);color:#fff}
.nav .nav-cta[aria-current="page"]{background:var(--space-900);color:var(--lime-2)}
.nav-toggle{display:none;margin-left:auto;background:none;border:1px solid var(--line);border-radius:10px;padding:.5rem;color:var(--ink);cursor:pointer}
@media (max-width:900px){
  .nav-toggle{display:inline-flex}
  .nav{display:none;position:absolute;left:0;right:0;top:100%;flex-direction:column;align-items:stretch;background:#fff;border-bottom:1px solid var(--line);padding:.5rem 16px 1rem;box-shadow:0 18px 30px -20px rgba(15,23,60,.4)}
  .nav.open{display:flex}
  .nav a{padding:.85rem .8rem}
}

/* Buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:.55rem;padding:.85rem 1.35rem;border-radius:12px;font:inherit;font-weight:750;text-decoration:none;border:2px solid transparent;cursor:pointer;line-height:1.2;transition:transform .15s ease,box-shadow .15s ease,background .15s ease}
.btn:hover{transform:translateY(-1px)}
.btn:active{transform:translateY(0)}
.btn-primary{background:var(--purple);color:#fff;box-shadow:0 10px 24px -12px rgba(91,63,224,.9)}
.btn-primary:hover{background:#4a2fc9;color:#fff}
.btn-lime{background:var(--lime);color:#0c1330;box-shadow:0 10px 30px -10px rgba(166,226,46,.55)}
.btn-lime:hover{background:var(--lime-2);color:#0c1330}
.btn-ghost{background:transparent;border-color:var(--purple);color:var(--purple)}
.btn-ghost:hover{background:#efeaff;color:#3d24b8}
.btn-ghost-dark{background:rgba(255,255,255,.06);border-color:rgba(255,255,255,.35);color:#fff}
.btn-ghost-dark:hover{background:rgba(255,255,255,.14);color:#fff}
.btn-sm{padding:.55rem .9rem;font-size:.95rem;border-radius:10px}
.btn[disabled],.btn[aria-disabled="true"]{opacity:.55;cursor:not-allowed;transform:none}
.btn-danger{background:var(--bad);color:#fff}
.btn-danger:hover{background:#921a17;color:#fff}

/* Sections */
.section{padding:clamp(3rem,6vw,5rem) 0}
.section-dark{background:radial-gradient(1200px 500px at 85% -10%,rgba(124,92,255,.25),transparent 60%),linear-gradient(180deg,var(--space-900),var(--space-950));color:var(--on-dark)}
.section-dark h1,.section-dark h2,.section-dark h3{color:#fff}
.section-dark p{color:var(--on-dark-2)}
.section-dark a:not(.btn){color:var(--lime-2)}
.section-graphite{background:linear-gradient(180deg,var(--graphite-800),var(--graphite-900));color:var(--on-dark)}
.section-graphite h2,.section-graphite h3{color:#fff}
.section-graphite p{color:var(--on-dark-2)}
.section-white{background:#fff}
.section-head{display:flex;justify-content:space-between;align-items:flex-end;gap:1rem;flex-wrap:wrap;margin-bottom:1.75rem}
.section-head h2{margin:0}
.section-head p{margin:.4rem 0 0;color:var(--ink-3);max-width:60ch}
.section-dark .section-head p,.section-graphite .section-head p{color:var(--on-dark-2)}
.eyebrow{display:inline-flex;align-items:center;gap:.5rem;font-size:.82rem;font-weight:800;letter-spacing:.12em;text-transform:uppercase;color:var(--cyan);margin-bottom:.9rem}
.section-dark .eyebrow,.section-graphite .eyebrow{color:var(--cyan-2)}
.link-arrow{display:inline-flex;align-items:center;gap:.4rem;font-weight:750;text-decoration:none}
.link-arrow:hover{gap:.65rem}

/* Hero */
.hero{position:relative;overflow:hidden;padding:clamp(3rem,7vw,6rem) 0 clamp(3.5rem,7vw,6rem)}
.hero::before{content:"";position:absolute;inset:0;background-image:linear-gradient(rgba(255,255,255,.045) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.045) 1px,transparent 1px);background-size:44px 44px;mask-image:radial-gradient(ellipse at 70% 30%,#000 10%,transparent 70%);-webkit-mask-image:radial-gradient(ellipse at 70% 30%,#000 10%,transparent 70%)}
.hero-inner{position:relative;display:grid;grid-template-columns:1.1fr .9fr;gap:2.5rem;align-items:center}
.hero h1{font-size:clamp(2.2rem,5.2vw,3.7rem);margin-bottom:1rem}
.hero h1 em{font-style:normal;background:linear-gradient(90deg,var(--cyan-2),var(--lime-2));-webkit-background-clip:text;background-clip:text;color:transparent}
.hero .lead{font-size:1.2rem;max-width:56ch;color:var(--on-dark-2)}
.hero-actions{display:flex;gap:.8rem;flex-wrap:wrap;margin-top:1.6rem}
.hero-note{margin-top:1.2rem;font-size:.95rem;color:var(--on-dark-2);display:flex;gap:1.2rem;flex-wrap:wrap}
.hero-note span{display:inline-flex;gap:.4rem;align-items:center}
.hero-art{position:relative;max-width:520px;justify-self:end;width:100%}
.hero-art svg{width:100%;height:auto;overflow:visible}
@media (max-width:860px){.hero-inner{grid-template-columns:1fr}.hero-art{justify-self:center;max-width:380px;order:-1}}
.page-hero{padding:clamp(2.2rem,5vw,3.6rem) 0}
.page-hero h1{margin-bottom:.6rem}
.page-hero .lead{font-size:1.15rem;max-width:64ch;margin:0}

/* Cards and grids */
.grid{display:grid;gap:1.25rem}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}
@media (max-width:980px){.grid-3,.grid-4{grid-template-columns:repeat(2,1fr)}}
@media (max-width:640px){.grid-3,.grid-2,.grid-4{grid-template-columns:1fr}}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);overflow:hidden;transition:transform .2s ease,box-shadow .2s ease}
.card:hover{transform:translateY(-3px);box-shadow:0 2px 4px rgba(15,23,60,.08),0 18px 36px -16px rgba(15,23,60,.35)}
.article-card{display:flex;flex-direction:column;height:100%}
.article-card .thumb{aspect-ratio:3/2;background:var(--paper-2);overflow:hidden}
.article-card .thumb img{width:100%;height:100%;object-fit:cover}
.article-card .body{padding:1.1rem 1.2rem 1.3rem;display:flex;flex-direction:column;gap:.5rem;flex:1}
.article-card h3{font-size:1.15rem;margin:0}
.article-card h3 a{color:var(--ink);text-decoration:none}
.article-card h3 a::after{content:"";position:absolute;inset:0}
.article-card{position:relative}
.article-card p{margin:0;color:var(--ink-2);font-size:.98rem}
.article-card .meta{margin-top:auto;font-size:.85rem;color:var(--ink-3);display:flex;gap:.9rem;flex-wrap:wrap}
.badge{display:inline-flex;align-items:center;gap:.35rem;font-size:.78rem;font-weight:800;letter-spacing:.04em;text-transform:uppercase;padding:.25rem .6rem;border-radius:999px;background:#efeaff;color:#4326b8;width:fit-content}
.badge-cyan{background:#dff6fb;color:#0a5a70}
.badge-lime{background:#eaf8c8;color:#3a5a0d}
.badge-easy{background:#e3f7ea;color:#0b5f2f}
.badge-medium{background:#fff2d1;color:#7a4a00}
.badge-hard{background:#fde3e3;color:#8f1d1a}
.cat-card{display:flex;flex-direction:column;gap:.6rem;padding:1.4rem;position:relative;height:100%}
.cat-card .cat-icon{width:52px;height:52px;border-radius:14px;display:grid;place-items:center;color:#fff}
.cat-card .cat-icon .icon{width:26px;height:26px}
.cat-card h3{margin:0;font-size:1.2rem}
.cat-card h3 a{color:var(--ink);text-decoration:none}
.cat-card h3 a::after{content:"";position:absolute;inset:0}
.cat-card p{margin:0;color:var(--ink-2);font-size:.98rem}
.cat-card .meta{margin-top:auto;font-size:.85rem;color:var(--ink-3)}
.c-1{background:linear-gradient(135deg,#5b3fe0,#8b6cff)}
.c-2{background:linear-gradient(135deg,#0e7490,#22b8d8)}
.c-3{background:linear-gradient(135deg,#8a6d00,#d6a800)}
.c-4{background:linear-gradient(135deg,#a3227f,#e0509f)}
.c-5{background:linear-gradient(135deg,#1f3a93,#4b74e8)}
.c-6{background:linear-gradient(135deg,#2f7d16,#6cbf2a)}

/* Daily challenge card */
.daily{display:grid;grid-template-columns:auto 1fr auto;gap:1.5rem;align-items:center;padding:1.6rem 1.8rem;border-radius:20px;background:linear-gradient(120deg,var(--space-800),var(--space-700) 60%,#3a2a8f);color:#fff;box-shadow:var(--shadow-lg);position:relative;overflow:hidden}
.daily::after{content:"";position:absolute;right:-60px;top:-60px;width:220px;height:220px;border-radius:50%;border:2px dashed rgba(255,255,255,.14)}
.daily .d-icon{width:64px;height:64px;border-radius:18px;background:rgba(166,226,46,.16);color:var(--lime-2);display:grid;place-items:center}
.daily .d-icon .icon{width:32px;height:32px}
.daily h2{margin:0 0 .3rem;color:#fff;font-size:1.5rem}
.daily p{margin:0;color:var(--on-dark-2)}
.daily .d-status{margin-top:.4rem;font-weight:700;color:var(--lime-2)}
@media (max-width:760px){.daily{grid-template-columns:1fr;text-align:left}}

/* Steps */
.steps{list-style:none;padding:0;margin:0;counter-reset:s;display:grid;grid-template-columns:repeat(4,1fr);gap:1.25rem}
.steps li{counter-increment:s;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:1.4rem;box-shadow:var(--shadow);position:relative}
.steps li::before{content:counter(s);display:grid;place-items:center;width:38px;height:38px;border-radius:12px;background:var(--space-900);color:var(--lime-2);font-weight:800;margin-bottom:.8rem}
.steps h3{font-size:1.1rem;margin-bottom:.35rem}
.steps p{margin:0;color:var(--ink-2);font-size:.98rem}
@media (max-width:980px){.steps{grid-template-columns:repeat(2,1fr)}}
@media (max-width:560px){.steps{grid-template-columns:1fr}}

/* Curiosity */
.curiosity{display:grid;grid-template-columns:1fr auto;gap:1.5rem;align-items:center;padding:2rem;border-radius:20px;background:#fff;border:1px solid var(--line);box-shadow:var(--shadow);border-left:6px solid var(--cyan-2)}
.curiosity blockquote{margin:0;font-size:clamp(1.2rem,2.2vw,1.55rem);line-height:1.4;font-weight:650;letter-spacing:-.01em}
.curiosity .c-actions{display:flex;flex-direction:column;gap:.6rem}
@media (max-width:760px){.curiosity{grid-template-columns:1fr}}

/* Explainers */
.explainers{display:grid;grid-template-columns:repeat(3,1fr);gap:1.25rem}
.explainer{background:rgba(255,255,255,.05);border:1px solid rgba(255,255,255,.14);border-radius:var(--radius);padding:1.5rem;backdrop-filter:blur(4px)}
.explainer h3{font-size:1.2rem;margin-bottom:.8rem;display:flex;gap:.6rem;align-items:center}
.explainer h3 .icon{color:var(--cyan-2)}
.explainer ol{padding-left:1.2rem;margin:0 0 1rem;color:var(--on-dark-2);font-size:.98rem}
.explainer li{margin-bottom:.4rem}
@media (max-width:980px){.explainers{grid-template-columns:1fr}}

/* Recently reviewed */
.review-list{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(2,1fr);gap:.75rem 1.5rem}
.review-list li{display:flex;justify-content:space-between;gap:1rem;padding:.9rem 0;border-bottom:1px solid var(--line);align-items:baseline}
.review-list a{font-weight:700;color:var(--ink);text-decoration:none}
.review-list a:hover{color:var(--purple);text-decoration:underline}
.review-list time{font-size:.85rem;color:var(--ink-3);white-space:nowrap}
@media (max-width:760px){.review-list{grid-template-columns:1fr}}

/* Breadcrumbs */
.breadcrumbs{font-size:.9rem;padding:1rem 0 0}
.breadcrumbs ol{list-style:none;display:flex;flex-wrap:wrap;gap:.35rem;padding:0;margin:0}
.breadcrumbs li{display:flex;gap:.35rem;align-items:center;color:var(--ink-3)}
.breadcrumbs li+li::before{content:"/";color:#9aa3bd}
.breadcrumbs a{color:var(--ink-2)}
.section-dark .breadcrumbs li,.section-dark .breadcrumbs a{color:var(--on-dark-2)}

/* Article */
.article-head{padding:1.2rem 0 1.6rem}
.article-head h1{font-size:clamp(2rem,4.4vw,3rem);max-width:22ch}
.article-meta{display:flex;flex-wrap:wrap;gap:.4rem 1.2rem;font-size:.92rem;color:var(--ink-3);margin:1rem 0 0}
.article-meta span{display:inline-flex;gap:.4rem;align-items:center}
.article-figure{margin:0 0 2rem}
.article-figure img{width:100%;aspect-ratio:2/1;max-height:460px;object-fit:cover;border-radius:18px;box-shadow:var(--shadow)}
@media (max-width:700px){.article-figure img{aspect-ratio:3/2}}.article-figure figcaption{font-size:.85rem;color:var(--ink-3);margin-top:.5rem}
.article-layout{display:grid;grid-template-columns:minmax(0,720px) 280px;gap:3rem;justify-content:center;align-items:start}
.prose{font-size:1.125rem;line-height:1.75}
.prose h2{margin-top:2.2em;padding-top:.2em;scroll-margin-top:90px}
.prose h3{margin-top:1.6em;scroll-margin-top:90px}
.prose p,.prose li{color:#1e2740}
.prose li{margin-bottom:.4em}
.prose strong{color:var(--ink)}
.prose>p:first-of-type{font-size:1.24rem;color:#111a36}
.toc{position:sticky;top:90px;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:1.1rem 1.2rem;font-size:.95rem}
.toc h2{font-size:.85rem;letter-spacing:.1em;text-transform:uppercase;color:var(--ink-3);margin-bottom:.6rem}
.toc ol{list-style:none;margin:0;padding:0}
.toc li{margin:0}
.toc a{display:block;padding:.35rem 0;color:var(--ink-2);text-decoration:none;border-left:3px solid transparent;padding-left:.7rem;margin-left:-.7rem}
.toc a:hover{color:var(--purple);border-left-color:var(--purple-3)}
.toc .toc-cta{margin-top:1rem;display:flex}.toc a.btn-primary{color:#fff;border-left:0;padding:.55rem .9rem;margin-left:0}.toc a.btn-primary:hover{color:#fff;background:#4a2fc9}.result-item h2{margin:0 0 .3rem;font-size:1.2rem}.src-block{border-bottom:1px solid var(--line);padding:.6rem 0}.src-block summary{cursor:pointer;font-weight:700}
@media (max-width:1000px){.article-layout{grid-template-columns:minmax(0,720px)}.toc{position:static;order:-1}}
.article-foot{margin-top:3rem;display:grid;gap:2rem}
.panel{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:1.5rem;box-shadow:var(--shadow)}
.panel h2{font-size:1.4rem}
.sources-list{margin:0;padding-left:1.2rem}
.sources-list li{margin-bottom:.6rem}
.sources-list .pub{color:var(--ink-3);font-size:.92rem}
.byline{font-size:.95rem;color:var(--ink-2);border-top:1px solid var(--line);padding-top:1rem}
.play-cta{display:flex;justify-content:space-between;align-items:center;gap:1rem;flex-wrap:wrap;background:linear-gradient(120deg,var(--space-800),var(--space-700));color:#fff;border-radius:var(--radius);padding:1.4rem 1.6rem}
.play-cta h2{color:#fff;margin:0 0 .2rem;font-size:1.3rem}
.play-cta p{margin:0;color:var(--on-dark-2)}

/* Mini quiz */
.mini-quiz{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:1.5rem;box-shadow:var(--shadow);border-top:5px solid var(--purple-2)}
.mini-quiz h2{font-size:1.4rem;margin-bottom:.3rem}
.mini-q{padding:1.2rem 0;border-top:1px solid var(--line)}
.mini-q:first-of-type{border-top:0}
.mini-q .q-text{font-weight:750;margin-bottom:.7rem}
.mini-q ul{list-style:none;padding:0;margin:0;display:grid;gap:.5rem}
.mini-opt{width:100%;text-align:left;font:inherit;background:var(--paper);border:2px solid var(--line);border-radius:12px;padding:.7rem .9rem;cursor:pointer;color:var(--ink);display:flex;gap:.7rem;align-items:center;transition:background .15s,border-color .15s}
.mini-opt:hover{border-color:var(--purple-3)}
.mini-opt[aria-disabled="true"]{cursor:default}
.mini-opt.is-correct{background:var(--ok-bg);border-color:var(--ok);color:#0a4a26}
.mini-opt.is-wrong{background:var(--bad-bg);border-color:var(--bad);color:#7d1512}
.mini-fb{margin-top:.7rem;padding:.8rem 1rem;border-radius:12px;background:var(--paper-2);font-size:.98rem}
.mini-score{margin-top:1rem;font-weight:750}

/* Filters / library */
.filters{display:flex;gap:.6rem;flex-wrap:wrap;align-items:center;margin-bottom:1.5rem}
.chip{font:inherit;font-weight:700;font-size:.92rem;padding:.5rem .95rem;border-radius:999px;border:2px solid var(--line);background:#fff;color:var(--ink);cursor:pointer}
.chip:hover{border-color:var(--purple-3)}
.chip[aria-pressed="true"]{background:var(--space-900);border-color:var(--space-900);color:#fff}
.input{font:inherit;padding:.75rem 1rem;border-radius:12px;border:2px solid var(--line);background:#fff;color:var(--ink);width:100%}
.input:focus{border-color:var(--purple-2);outline:none;box-shadow:0 0 0 4px rgba(124,92,255,.25)}
label.lbl{display:block;font-weight:700;margin-bottom:.35rem}
.search-form{display:flex;gap:.6rem;max-width:560px}
.search-form .input{flex:1}
.result-item{padding:1.2rem 0;border-bottom:1px solid var(--line)}
.result-item h3{margin:0 0 .3rem;font-size:1.2rem}
.result-item p{margin:0;color:var(--ink-2)}
.result-item .kind{font-size:.8rem;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:var(--cyan)}
mark{background:#e9fbb3;color:inherit;padding:0 .1em;border-radius:3px}

/* Forms */
.form-grid{display:grid;gap:1.1rem}
.field{display:grid}
textarea.input{min-height:150px;resize:vertical}
.notice{padding:1rem 1.2rem;border-radius:12px;background:#eef9ff;border:1px solid #bde6f5;color:#0b4358}
.notice.ok{background:var(--ok-bg);border-color:#a8dfbd;color:#0a4a26}

/* Policy pages */
.policy h2{margin-top:2em;font-size:1.5rem}
.policy h3{margin-top:1.4em}
.policy .updated{color:var(--ink-3);font-size:.95rem}
.data-table{width:100%;border-collapse:collapse;font-size:.95rem;background:#fff;border:1px solid var(--line);border-radius:12px;overflow:hidden}
.data-table th,.data-table td{text-align:left;padding:.75rem .9rem;border-bottom:1px solid var(--line);vertical-align:top}
.data-table th{background:var(--paper-2);font-size:.85rem;text-transform:uppercase;letter-spacing:.06em;color:var(--ink-2)}
.table-wrap{overflow-x:auto}

/* Quiz */
.quiz-page .page-hero{padding-bottom:2.4rem}
.setup-layout{display:grid;grid-template-columns:minmax(0,1fr) 340px;gap:2rem;align-items:start}
@media (max-width:1000px){.setup-layout{grid-template-columns:1fr}}
fieldset.q-fieldset{border:0;padding:0;margin:0 0 1.8rem;min-width:0}
fieldset.q-fieldset legend{font-size:1.15rem;font-weight:800;margin-bottom:.8rem;padding:0;letter-spacing:-.01em}
.choice-grid{display:grid;gap:.7rem;grid-template-columns:repeat(auto-fill,minmax(220px,1fr))}
.choice-grid.compact{grid-template-columns:repeat(auto-fill,minmax(140px,1fr))}
.choice{position:relative;display:block}
.choice input{position:absolute;opacity:0;inset:0;width:100%;height:100%;margin:0;cursor:pointer}
.choice .cb{display:flex;align-items:center;gap:.75rem;padding:.85rem 1rem;border-radius:14px;background:#fff;border:2px solid var(--line);font-weight:700;transition:border-color .15s,background .15s,box-shadow .15s;min-height:58px}
.choice .cb small{display:block;font-weight:500;color:var(--ink-3);font-size:.82rem}
.choice .cb .ci{width:38px;height:38px;border-radius:11px;display:grid;place-items:center;color:#fff;flex:none}
.choice input:hover+.cb{border-color:var(--purple-3)}
.choice input:checked+.cb{border-color:var(--purple);background:#f3efff;box-shadow:0 0 0 3px rgba(91,63,224,.16)}
.choice input:focus-visible+.cb{outline:3px solid var(--focus);outline-offset:2px}
.notice-line{min-height:1.6em;font-size:.95rem;color:var(--ink-2);margin:.2rem 0 1.2rem}
.side-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:1.4rem;box-shadow:var(--shadow)}
.side-card h2{font-size:1.2rem}
.rec-list{list-style:none;padding:0;margin:0 0 1rem;display:grid;gap:.6rem;font-size:.95rem}
.rec-list li{display:flex;justify-content:space-between;gap:.6rem;border-bottom:1px dashed var(--line);padding-bottom:.5rem}
.rec-list b{white-space:nowrap}
.stat-row{display:flex;gap:1rem;flex-wrap:wrap;margin:0 0 1rem}
.stat{flex:1;min-width:90px;background:var(--paper);border-radius:12px;padding:.7rem .9rem}
.stat b{display:block;font-size:1.4rem;line-height:1.1}
.stat span{font-size:.8rem;color:var(--ink-3)}
.resume{display:flex;gap:1rem;align-items:center;justify-content:space-between;flex-wrap:wrap;padding:1rem 1.2rem;border-radius:14px;background:#efeaff;border:1px solid #d6cbff;margin-bottom:1.5rem}
.resume p{margin:0;font-weight:650}
.stage{background:radial-gradient(800px 380px at 90% -20%,rgba(124,92,255,.35),transparent 60%),linear-gradient(180deg,#111a45,#0a1030);color:var(--on-dark);border-radius:24px;padding:clamp(1.2rem,3vw,2.2rem);box-shadow:var(--shadow-lg);border:1px solid rgba(255,255,255,.1)}
.stage-top{display:flex;justify-content:space-between;align-items:center;gap:1rem;flex-wrap:wrap;margin-bottom:.9rem}
.stage .q-count{font-weight:700;color:var(--on-dark-2);font-size:.95rem}
.stage .tags{display:flex;gap:.5rem;flex-wrap:wrap}
.progress{height:10px;border-radius:999px;background:rgba(255,255,255,.14);overflow:hidden;margin-bottom:1.4rem}
.progress>span{display:block;height:100%;width:0;border-radius:999px;background:linear-gradient(90deg,var(--cyan-2),var(--lime));transition:width .45s cubic-bezier(.2,.8,.2,1)}
.q-body{animation:qin .4s ease both}
.q-title{font-size:clamp(1.3rem,2.6vw,1.75rem);line-height:1.3;color:#fff;margin:0 0 1.3rem;letter-spacing:-.01em}
.q-title:focus{outline:none}
.options{list-style:none;padding:0;margin:0;display:grid;gap:.75rem}
.opt{width:100%;display:flex;align-items:center;gap:.9rem;text-align:left;font:inherit;font-size:1.05rem;color:#fff;background:rgba(255,255,255,.07);border:2px solid rgba(255,255,255,.18);border-radius:14px;padding:.9rem 1rem;cursor:pointer;transition:transform .15s,background .15s,border-color .15s}
.opt:hover{background:rgba(255,255,255,.13);border-color:var(--cyan-2);transform:translateX(3px)}
.opt .key{flex:none;width:34px;height:34px;border-radius:10px;display:grid;place-items:center;background:rgba(255,255,255,.14);font-weight:800;font-size:.95rem}
.opt .txt{flex:1}
.opt .mark{flex:none;width:28px;height:28px;display:none;place-items:center;border-radius:50%}
.opt .mark .icon{width:18px;height:18px}
.opt[aria-disabled="true"]{cursor:default;transform:none}
.opt[aria-disabled="true"]:hover{transform:none;background:rgba(255,255,255,.07);border-color:rgba(255,255,255,.18)}
.opt.is-correct{background:rgba(52,199,110,.2);border-color:#43d17f;animation:pulse .5s ease}
.opt.is-correct .key{background:#43d17f;color:#04220f}
.opt.is-correct .mark{display:grid;background:#43d17f;color:#04220f}
.opt.is-wrong{background:rgba(255,92,92,.18);border-color:#ff7b7b;animation:shake .45s ease}
.opt.is-wrong .key{background:#ff7b7b;color:#2a0505}
.opt.is-wrong .mark{display:grid;background:#ff7b7b;color:#2a0505}
.opt.is-dim{opacity:.55}
.feedback{margin-top:1.3rem;border-radius:16px;padding:1.2rem 1.3rem;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.16);animation:qin .35s ease both}
.feedback:focus{outline:3px solid var(--cyan-2);outline-offset:2px}
.feedback.fb-ok{border-color:#43d17f;background:rgba(52,199,110,.12)}
.feedback.fb-bad{border-color:#ff7b7b;background:rgba(255,92,92,.1)}
.feedback h3{font-size:1.25rem;margin:0 0 .4rem;display:flex;gap:.5rem;align-items:center;color:#fff}
.feedback p{color:#dfe5ff;margin:0 0 .8rem}
.feedback .refs{display:flex;gap:1.2rem;flex-wrap:wrap;margin-bottom:1rem;font-size:.95rem}
.feedback .refs a{color:var(--lime-2)}
.stage .btn-lime{margin-top:.2rem}
.stage-foot{display:flex;justify-content:space-between;align-items:center;gap:1rem;margin-top:1.4rem;flex-wrap:wrap}
.stage-foot .quit{background:none;border:0;color:var(--on-dark-2);font:inherit;text-decoration:underline;cursor:pointer;padding:.3rem}
.stage-foot .kbd{font-size:.85rem;color:var(--on-dark-2)}
kbd{font-family:var(--mono);font-size:.85em;background:rgba(255,255,255,.14);border-radius:6px;padding:.1em .45em}
.result-top{display:grid;grid-template-columns:auto 1fr;gap:2rem;align-items:center}
@media (max-width:640px){.result-top{grid-template-columns:1fr;justify-items:center;text-align:center}}
.ring{position:relative;width:170px;height:170px}
.ring svg{width:170px;height:170px;transform:rotate(-90deg)}
.ring circle{fill:none;stroke-width:12}
.ring .bg{stroke:rgba(255,255,255,.15)}
.ring .fg{stroke:url(#ringGrad);stroke-linecap:round;transition:stroke-dashoffset 1.2s cubic-bezier(.2,.8,.2,1)}
.ring .pct{position:absolute;inset:0;display:grid;place-items:center;font-size:2.4rem;font-weight:850;color:#fff;letter-spacing:-.03em}
.result-top h2{color:#fff;margin:0 0 .3rem}
.result-top p{margin:0 0 .3rem;color:var(--on-dark-2)}
.result-stats{display:flex;gap:1.5rem;flex-wrap:wrap;margin:.8rem 0 0}
.result-stats div b{display:block;font-size:1.5rem;color:#fff}
.result-stats div span{font-size:.85rem;color:var(--on-dark-2)}
.record-badge{display:inline-flex;gap:.4rem;align-items:center;background:var(--lime);color:#0c1330;font-weight:800;border-radius:999px;padding:.3rem .8rem;font-size:.9rem;margin-bottom:.6rem}
.cat-bars{list-style:none;padding:0;margin:1.6rem 0 0;display:grid;gap:.9rem}
.cat-bars li{display:grid;gap:.3rem}
.cat-bars .row{display:flex;justify-content:space-between;font-weight:650;color:#fff;font-size:.98rem}
.cat-bars .bar{height:10px;border-radius:999px;background:rgba(255,255,255,.14);overflow:hidden}
.cat-bars .bar span{display:block;height:100%;background:linear-gradient(90deg,var(--purple-2),var(--cyan-2));border-radius:999px}
.result-actions{display:flex;gap:.7rem;flex-wrap:wrap;margin-top:1.8rem}
.read-next{margin-top:1.8rem;border-top:1px solid rgba(255,255,255,.14);padding-top:1.3rem}
.read-next h3{font-size:1.1rem;color:#fff}
.read-next ul{margin:0;padding-left:1.1rem;color:var(--on-dark-2)}
.read-next a{color:var(--lime-2)}
.status-msg{margin-top:.8rem;font-size:.95rem;color:var(--lime-2);min-height:1.4em}
.review-head{display:flex;justify-content:space-between;align-items:center;gap:1rem;flex-wrap:wrap;margin-bottom:1.2rem}
.review-head h2{margin:0;color:#fff}
.review-item{background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.14);border-radius:16px;padding:1.2rem 1.3rem;margin-bottom:1rem}
.review-item.r-ok{border-left:6px solid #43d17f}
.review-item.r-bad{border-left:6px solid #ff7b7b}
.review-item h3{font-size:1.1rem;color:#fff;margin:.4rem 0 .8rem;line-height:1.35}
.review-item .ans{margin:0 0 .35rem;color:#e6ebff}
.review-item .ans b{color:#fff}
.review-item .why{margin:.7rem 0;color:#cdd5f5}
.review-item .refs a{color:var(--lime-2);font-size:.95rem;margin-right:1.1rem}
.tag-ok{color:#5fe39a;font-weight:800}
.tag-bad{color:#ff9a9a;font-weight:800}
.daily-summary{display:grid;gap:1rem}
dialog{border:0;border-radius:18px;padding:1.6rem;max-width:min(440px,92vw);box-shadow:var(--shadow-lg);color:var(--ink)}
dialog::backdrop{background:rgba(7,11,29,.65)}
dialog h2{font-size:1.3rem}
dialog .d-actions{display:flex;gap:.6rem;justify-content:flex-end;margin-top:1.2rem;flex-wrap:wrap}
@keyframes qin{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:none}}
@keyframes pulse{0%{transform:scale(1)}40%{transform:scale(1.025)}100%{transform:scale(1)}}
@keyframes shake{0%,100%{transform:translateX(0)}20%{transform:translateX(-6px)}40%{transform:translateX(6px)}60%{transform:translateX(-4px)}80%{transform:translateX(3px)}}
@keyframes float{0%,100%{transform:translateY(0)}50%{transform:translateY(-8px)}}
@keyframes orbit{to{transform:rotate(360deg)}}
@keyframes pulseNode{0%,100%{opacity:.35}50%{opacity:1}}
.hero-art .sat{animation:float 6s ease-in-out infinite;transform-origin:center}
.hero-art .orb{transform-origin:260px 250px;animation:orbit 40s linear infinite}
.hero-art .node{animation:pulseNode 3.2s ease-in-out infinite}
.hero-art .node:nth-child(2n){animation-delay:.8s}
.hero-art .node:nth-child(3n){animation-delay:1.6s}

/* Footer */
.site-footer{background:var(--space-950);color:var(--on-dark-2);margin-top:auto;padding:3.2rem 0 1.6rem;border-top:1px solid rgba(255,255,255,.08)}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:2rem}
@media (max-width:860px){.footer-grid{grid-template-columns:1fr 1fr}}
@media (max-width:520px){.footer-grid{grid-template-columns:1fr}}
.site-footer h2{font-size:.85rem;letter-spacing:.12em;text-transform:uppercase;color:#fff;margin-bottom:.9rem}
.site-footer ul{list-style:none;padding:0;margin:0}
.site-footer li{margin-bottom:.45rem}
.site-footer a{color:var(--on-dark-2);text-decoration:none}
.site-footer a:hover{color:#fff;text-decoration:underline}
.footer-brand{display:flex;align-items:center;gap:.7rem;color:#fff;font-weight:800;font-size:1.2rem;margin-bottom:.8rem}
.footer-brand img{width:44px;height:44px}
.footer-note{max-width:38ch;font-size:.95rem}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);margin-top:2.2rem;padding-top:1.2rem;display:flex;justify-content:space-between;gap:1rem;flex-wrap:wrap;font-size:.9rem}

/* 404 */
.nf-code{font-size:clamp(4rem,14vw,8rem);font-weight:900;line-height:1;background:linear-gradient(90deg,var(--purple-2),var(--cyan-2),var(--lime));-webkit-background-clip:text;background-clip:text;color:transparent;letter-spacing:-.05em}

@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important;scroll-behavior:auto!important}
}
@media (forced-colors:active){.opt,.choice .cb,.btn{border:2px solid ButtonText}.progress>span{background:Highlight}}
@media print{.site-header,.site-footer,.toc,.mini-quiz,.play-cta{display:none}body{background:#fff}}