/* Class E Knowledge Exam - classeknowledgeexam.com
   Design system + components. No framework, self-contained. */

:root{
  --blue:#0F62D6;
  --blue-dark:#0A2540;
  --blue-700:#0B4FB0;
  --navy:#0A2540;
  --green:#16A34A;
  --green-700:#15803D;
  --red:#E11D48;
  --amber:#F2B705;
  --bg:#FFFFFF;
  --surface:#F4F8FD;
  --surface-2:#EAF1FB;
  --line:#E2E8F2;
  --text:#13243B;
  --muted:#5B6B82;
  --white:#fff;
  --radius:14px;
  --radius-sm:10px;
  --shadow:0 6px 24px rgba(12,42,84,.08);
  --shadow-lg:0 18px 50px rgba(12,42,84,.16);
  --maxw:1140px;
  --font:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;font-family:var(--font);color:var(--text);background:var(--bg);
  line-height:1.6;font-size:17px;-webkit-font-smoothing:antialiased;
}
img{max-width:100%;height:auto;display:block}
a{color:var(--blue);text-decoration:none}
a:hover{text-decoration:underline}
h1,h2,h3,h4{line-height:1.2;margin:0 0 .5em;color:var(--navy);font-weight:800;letter-spacing:-.01em}
h1{font-size:clamp(2rem,4.5vw,3.1rem)}
h2{font-size:clamp(1.6rem,3.2vw,2.3rem)}
h3{font-size:1.25rem}
p{margin:0 0 1rem}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}
.section{padding:64px 0}
.section--tight{padding:44px 0}
.section--surface{background:var(--surface)}
.center{text-align:center}
.lead{font-size:1.2rem;color:var(--muted);max-width:720px;margin:0 auto 1.5rem}
.eyebrow{display:inline-block;font-weight:700;font-size:.8rem;letter-spacing:.12em;text-transform:uppercase;color:var(--blue);background:var(--surface-2);padding:6px 14px;border-radius:999px;margin-bottom:14px}

/* Buttons */
.btn{display:inline-flex;align-items:center;gap:8px;font-weight:700;font-size:1rem;
  padding:13px 26px;border-radius:999px;border:2px solid transparent;cursor:pointer;
  transition:transform .12s ease,box-shadow .12s ease,background .12s ease;text-decoration:none}
.btn:hover{text-decoration:none;transform:translateY(-1px)}
.btn--primary{background:var(--blue);color:#fff;box-shadow:0 8px 20px rgba(15,98,214,.28)}
.btn--primary:hover{background:var(--blue-700);color:#fff}
.btn--green{background:var(--green);color:#fff;box-shadow:0 8px 20px rgba(22,163,74,.28)}
.btn--green:hover{background:var(--green-700);color:#fff}
.btn--outline{background:#fff;color:var(--blue);border-color:var(--line)}
.btn--outline:hover{border-color:var(--blue);color:var(--blue)}
.btn--lg{padding:16px 34px;font-size:1.08rem}
.btn--block{display:flex;width:100%;justify-content:center}
.btn--ghost{background:transparent;color:var(--navy)}

/* Header */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);
  backdrop-filter:saturate(180%) blur(10px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;justify-content:space-between;height:70px;gap:18px}
.brand{display:flex;align-items:center;gap:10px;font-weight:900;color:var(--navy);font-size:1.12rem;letter-spacing:-.02em}
.brand:hover{text-decoration:none}
.brand .mark{width:34px;height:34px;border-radius:9px;background:linear-gradient(135deg,var(--blue),#3B82F6);
  color:#fff;display:grid;place-items:center;font-weight:900;font-size:1rem;box-shadow:0 4px 10px rgba(15,98,214,.35)}
.brand small{display:block;font-size:.62rem;color:var(--muted);font-weight:600;letter-spacing:.06em;text-transform:uppercase}
.nav-links{display:flex;align-items:center;gap:6px;list-style:none;margin:0;padding:0}
.nav-links a{color:var(--navy);font-weight:600;font-size:.97rem;padding:9px 12px;border-radius:8px;white-space:nowrap}
.nav-links a:hover{background:var(--surface);text-decoration:none}
.nav-cta{display:flex;align-items:center;gap:10px}
.has-drop{position:relative}
.has-drop>a::after{content:"▾";font-size:.7rem;margin-left:5px;color:var(--muted)}
.drop{position:absolute;top:calc(100% + 6px);left:0;min-width:230px;background:#fff;border:1px solid var(--line);
  border-radius:12px;box-shadow:var(--shadow-lg);padding:8px;opacity:0;visibility:hidden;transform:translateY(6px);
  transition:.16s ease}
.has-drop:hover .drop{opacity:1;visibility:visible;transform:translateY(0)}
.drop a{display:block;padding:10px 12px;border-radius:8px;color:var(--navy);font-weight:600;font-size:.92rem}
.drop a:hover{background:var(--surface)}
.nav-toggle{display:none;background:none;border:0;cursor:pointer;padding:8px}
.nav-toggle span{display:block;width:24px;height:2px;background:var(--navy);margin:5px 0;border-radius:2px;transition:.2s}

/* Hero */
.hero{position:relative;background:radial-gradient(1200px 500px at 80% -10%,#1E73E8 0%,var(--blue) 35%,var(--blue-dark) 100%);
  color:#fff;overflow:hidden}
.hero::after{content:"";position:absolute;inset:0;background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='40' height='40'%3E%3Cpath d='M0 39h40M39 0v40' stroke='%23ffffff' stroke-opacity='.05' stroke-width='1'/%3E%3C/svg%3E");opacity:.6}
.hero-inner{position:relative;display:grid;grid-template-columns:1.15fr .85fr;gap:40px;align-items:center;padding:72px 0 84px}
.hero h1{color:#fff}
.hero p{color:rgba(255,255,255,.86);font-size:1.18rem;max-width:560px}
.hero .badge{display:inline-flex;align-items:center;gap:8px;background:rgba(255,255,255,.14);
  border:1px solid rgba(255,255,255,.22);color:#fff;padding:7px 15px;border-radius:999px;font-weight:600;font-size:.88rem;margin-bottom:18px}
.hero-cta{display:flex;flex-wrap:wrap;gap:14px;margin-top:26px}
.hero-stats{display:flex;gap:26px;margin-top:34px;flex-wrap:wrap}
.hero-stats .s{display:flex;flex-direction:column}
.hero-stats .s b{font-size:1.7rem;font-weight:900;line-height:1}
.hero-stats .s span{color:rgba(255,255,255,.75);font-size:.85rem;margin-top:4px}

/* Hero card (sample question preview) */
.hero-card{background:#fff;border-radius:18px;box-shadow:var(--shadow-lg);padding:24px;color:var(--text)}
.hero-card .q-tag{font-size:.78rem;font-weight:700;color:var(--blue);text-transform:uppercase;letter-spacing:.08em}
.hero-card h3{margin:8px 0 16px;color:var(--navy);font-size:1.18rem}
.hero-card .opt{display:flex;align-items:center;gap:12px;border:1px solid var(--line);border-radius:10px;padding:12px 14px;margin-bottom:10px;font-weight:600;font-size:.95rem}
.hero-card .opt .k{width:26px;height:26px;border-radius:7px;background:var(--surface);display:grid;place-items:center;font-weight:800;color:var(--muted);flex:none}
.hero-card .opt.correct{border-color:var(--green);background:rgba(22,163,74,.07)}
.hero-card .opt.correct .k{background:var(--green);color:#fff}
.hero-card .hint{font-size:.84rem;color:var(--muted);margin:6px 0 0}

/* Grid + cards */
.grid{display:grid;gap:22px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px;box-shadow:var(--shadow);transition:transform .15s ease,box-shadow .15s ease}
.card:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg)}
.card .ico{width:50px;height:50px;border-radius:12px;background:var(--surface-2);display:grid;place-items:center;font-size:1.5rem;margin-bottom:14px}
.card h3{margin-bottom:8px}
.card p{color:var(--muted);margin:0;font-size:.97rem}

/* clickable category/test card */
.test-card{display:flex;flex-direction:column;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow);transition:transform .15s,box-shadow .15s;height:100%}
.test-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg);text-decoration:none}
.test-card .ico{font-size:1.9rem;margin-bottom:12px}
.test-card h3{color:var(--navy);margin-bottom:6px}
.test-card p{color:var(--muted);font-size:.95rem;flex:1}
.test-card .meta{margin-top:14px;display:flex;gap:14px;color:var(--muted);font-size:.85rem;font-weight:600}
.test-card .meta b{color:var(--blue)}

/* Steps */
.steps{counter-reset:step;display:grid;gap:20px}
.step{display:flex;gap:18px;align-items:flex-start;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px}
.step .num{counter-increment:step;flex:none;width:44px;height:44px;border-radius:50%;background:var(--blue);color:#fff;display:grid;place-items:center;font-weight:900;font-size:1.1rem}
.step .num::before{content:counter(step)}
.step h3{margin-bottom:4px}
.step p{margin:0;color:var(--muted);font-size:.96rem}

/* Detail / meta box */
.factbox{background:var(--navy);color:#fff;border-radius:var(--radius);padding:28px;display:grid;grid-template-columns:repeat(2,1fr);gap:18px 28px}
.factbox .f b{display:block;font-size:1.5rem;font-weight:900;color:#fff}
.factbox .f span{color:rgba(255,255,255,.7);font-size:.9rem}

/* Pills / category chips */
.pills{display:flex;flex-wrap:wrap;gap:10px}
.pill{background:var(--surface-2);color:var(--blue-700);font-weight:700;font-size:.88rem;padding:8px 15px;border-radius:999px}

/* FAQ accordion */
.faq{max-width:820px;margin:0 auto}
.faq details{background:#fff;border:1px solid var(--line);border-radius:12px;margin-bottom:12px;overflow:hidden}
.faq summary{cursor:pointer;padding:18px 22px;font-weight:700;color:var(--navy);list-style:none;display:flex;justify-content:space-between;align-items:center;gap:14px}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";font-size:1.4rem;color:var(--blue);font-weight:700;flex:none}
.faq details[open] summary::after{content:"\2013"}
.faq .a{padding:0 22px 18px;color:var(--muted)}
.faq .a p{margin:0 0 .6em}

/* Testimonials */
.quote{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow)}
.quote p{font-style:italic;color:var(--text)}
.quote .by{display:flex;align-items:center;gap:12px;margin-top:14px}
.quote .av{width:40px;height:40px;border-radius:50%;background:var(--surface-2);display:grid;place-items:center;font-weight:800;color:var(--blue)}
.quote .by b{display:block;color:var(--navy)}
.quote .by span{color:var(--muted);font-size:.85rem}
.stars{color:var(--amber);letter-spacing:2px}

/* prose (article/guide pages) */
.prose{max-width:780px;margin:0 auto;font-size:1.05rem}
.prose h2{margin-top:1.8em}
.prose h3{margin-top:1.4em;color:var(--blue-dark)}
.prose ul,.prose ol{padding-left:1.3em;margin:0 0 1.2em}
.prose li{margin-bottom:.5em}
.prose .callout{background:var(--surface);border-left:4px solid var(--blue);border-radius:8px;padding:16px 20px;margin:1.4em 0;color:var(--text)}
.prose table{width:100%;border-collapse:collapse;margin:1.2em 0}
.prose th,.prose td{border:1px solid var(--line);padding:10px 14px;text-align:left}
.prose th{background:var(--surface-2);color:var(--navy)}

/* Disclaimer / notice */
.notice{background:var(--surface);border:1px solid var(--line);border-left:4px solid var(--amber);border-radius:10px;padding:14px 18px;color:var(--muted);font-size:.88rem;margin:20px 0;line-height:1.55}
.notice b{color:var(--navy)}

/* Page hero (inner pages) */
.page-hero{background:linear-gradient(120deg,var(--blue),var(--blue-dark));color:#fff;padding:54px 0}
.page-hero h1{color:#fff;margin-bottom:8px}
.page-hero p{color:rgba(255,255,255,.85);margin:0;max-width:680px}
.crumbs{font-size:.85rem;color:rgba(255,255,255,.7);margin-bottom:14px}
.crumbs a{color:rgba(255,255,255,.9)}

/* CTA band */
.cta-band{background:linear-gradient(120deg,var(--green),#0E8A41);color:#fff;border-radius:18px;padding:42px;text-align:center}
.cta-band h2{color:#fff}
.cta-band p{color:rgba(255,255,255,.9);max-width:600px;margin:0 auto 22px}

/* ===== Quiz engine ===== */
.quiz-wrap{max-width:780px;margin:0 auto}
.quiz-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px;gap:14px;flex-wrap:wrap}
.quiz-top .label{font-weight:700;color:var(--navy)}
.quiz-top .score{font-weight:700;color:var(--muted)}
.progress{height:10px;background:var(--surface-2);border-radius:999px;overflow:hidden;margin-bottom:26px}
.progress > i{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--blue),#3B82F6);transition:width .35s ease}
.qcard{background:#fff;border:1px solid var(--line);border-radius:16px;box-shadow:var(--shadow);padding:30px}
.qcat{font-size:.78rem;font-weight:700;text-transform:uppercase;letter-spacing:.08em;color:var(--blue)}
.qtext{font-size:1.35rem;font-weight:800;color:var(--navy);margin:8px 0 22px}
.qimg{max-width:200px;margin:0 auto 18px}
.options{display:grid;gap:12px}
.option{display:flex;align-items:center;gap:14px;width:100%;text-align:left;border:2px solid var(--line);background:#fff;
  border-radius:12px;padding:15px 18px;font-size:1.02rem;font-weight:600;color:var(--text);cursor:pointer;transition:.12s}
.option:hover:not(:disabled){border-color:var(--blue);background:var(--surface)}
.option.sel{border-color:var(--blue);background:var(--surface-2)}
.option.sel .key{background:var(--blue);color:#fff}
.option .key{flex:none;width:30px;height:30px;border-radius:8px;background:var(--surface);display:grid;place-items:center;font-weight:800;color:var(--muted)}
.option.correct{border-color:var(--green);background:rgba(22,163,74,.08)}
.option.correct .key{background:var(--green);color:#fff}
.option.wrong{border-color:var(--red);background:rgba(225,29,72,.07)}
.option.wrong .key{background:var(--red);color:#fff}
.option:disabled{cursor:default}
.explain{margin-top:18px;border-radius:12px;padding:16px 18px;background:var(--surface);border-left:4px solid var(--blue);display:none}
.explain.show{display:block}
.explain b{color:var(--navy)}
.quiz-actions{display:flex;justify-content:space-between;margin-top:24px;gap:12px}
.flag-tip{font-size:.82rem;color:var(--muted);margin-top:14px;text-align:center}

/* Result screen */
.result{background:#fff;border:1px solid var(--line);border-radius:16px;box-shadow:var(--shadow);padding:40px;text-align:center}
.result .ring{width:150px;height:150px;border-radius:50%;display:grid;place-items:center;margin:0 auto 18px;
  background:conic-gradient(var(--c,var(--blue)) var(--deg,0deg),var(--surface-2) 0deg)}
.result .ring .inner{width:118px;height:118px;border-radius:50%;background:#fff;display:grid;place-items:center;flex-direction:column}
.result .ring .pct{font-size:2.2rem;font-weight:900;color:var(--navy);line-height:1}
.result .ring .sub{font-size:.78rem;color:var(--muted)}
.result h2{margin:6px 0}
.result .verdict{display:inline-block;font-weight:800;padding:6px 18px;border-radius:999px;margin-bottom:10px}
.result .verdict.pass{background:rgba(22,163,74,.12);color:var(--green-700)}
.result .verdict.fail{background:rgba(225,29,72,.1);color:var(--red)}
.result .res-actions{display:flex;gap:12px;justify-content:center;flex-wrap:wrap;margin-top:22px}
.hidden{display:none!important}

/* Footer */
.site-footer{background:var(--navy);color:rgba(255,255,255,.72);padding:54px 0 28px;margin-top:20px}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:30px}
.site-footer h4{color:#fff;font-size:.95rem;margin-bottom:14px;text-transform:uppercase;letter-spacing:.05em}
.site-footer a{color:rgba(255,255,255,.72);display:block;padding:5px 0;font-size:.93rem}
.site-footer a:hover{color:#fff;text-decoration:none}
.site-footer .about p{font-size:.92rem;line-height:1.6}
.footer-bottom{border-top:1px solid rgba(255,255,255,.12);margin-top:34px;padding-top:20px;display:flex;justify-content:space-between;gap:14px;flex-wrap:wrap;font-size:.85rem}
.disclaimer{font-size:.8rem;color:rgba(255,255,255,.5);margin-top:10px;max-width:760px}

/* Responsive */
@media(max-width:900px){
  .hero-inner{grid-template-columns:1fr;padding:54px 0 60px}
  .hero-card{order:2}
  .grid-3,.grid-4{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:680px){
  body{font-size:16px}
  .nav-links{position:fixed;inset:70px 0 auto 0;background:#fff;flex-direction:column;align-items:stretch;
    padding:14px 20px;gap:2px;border-bottom:1px solid var(--line);box-shadow:var(--shadow);display:none}
  .nav-links.open{display:flex}
  .nav-links a{padding:12px 10px;border-radius:8px}
  .has-drop .drop{position:static;opacity:1;visibility:visible;transform:none;box-shadow:none;border:0;padding:0 0 0 14px}
  .nav-toggle{display:block}
  .grid-2,.grid-3,.grid-4{grid-template-columns:1fr}
  .factbox{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .section{padding:46px 0}
  .quiz-actions{flex-direction:column-reverse}
  .btn--block-m{display:flex;width:100%;justify-content:center}
}