:root{--bg:#f7f8fb;--card:#fff;--ink:#0f172a;--mute:#64748b;--line:#e4e7ee;--pri:#1d4ed8;--pri2:#2563eb;--soft:#eef3ff;--ok:#16a34a;--bad:#dc2626;--yel:#facc15;--r:18px;--max:1180px}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.55 system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,"PingFang SC","Noto Sans SC",sans-serif}
a{color:var(--pri)}
img{max-width:100%}
.wrap{max-width:var(--max);margin:0 auto;padding:0 16px}

/* header */
.top{position:sticky;top:0;z-index:20;background:#fff;border-bottom:1px solid var(--line)}
.top .wrap{display:flex;align-items:center;gap:16px;height:64px}
.brand{display:flex;align-items:center;gap:9px;font-weight:800;font-size:21px;letter-spacing:-.03em;color:var(--ink);text-decoration:none;white-space:nowrap}
.brand svg{width:30px;height:30px;flex:none}
.menu{display:flex;gap:4px;margin:0 auto}
.menu a{padding:9px 14px;border-radius:10px;color:#334155;text-decoration:none;font-weight:500;white-space:nowrap}
.menu a:hover{background:#f1f5f9}
.menu a[aria-current]{background:var(--soft);color:var(--pri);box-shadow:inset 0 0 0 1px #dbe5ff}
.cta{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:11px 20px;border-radius:12px;border:0;background:linear-gradient(180deg,var(--pri2),var(--pri));color:#fff;font:600 16px/1.2 inherit;text-decoration:none;cursor:pointer;box-shadow:0 1px 0 rgba(255,255,255,.25) inset,0 2px 6px rgba(29,78,216,.25);white-space:nowrap}
.cta:hover{filter:brightness(1.07)}
.cta.ghost{background:#fff;color:var(--pri);border:1px solid #d5dbe6;box-shadow:0 1px 2px rgba(15,23,42,.05)}
.cta.lg{padding:15px 26px;font-size:17px}
.burger{display:none;margin-left:auto;background:none;border:0;padding:8px;cursor:pointer}
.burger svg{width:26px;height:26px}
@media (max-width:820px){
 .menu{display:none;position:absolute;top:64px;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);flex-direction:column;padding:8px 16px 14px}
 .menu.open{display:flex}
 .top .cta{display:none}
 .burger{display:block}
}

/* hero */
.hero{text-align:center;padding:56px 0 18px}
.hero h1{font-size:clamp(28px,4.6vw,46px);line-height:1.12;letter-spacing:-.03em;margin:0 0 12px;font-weight:800}
.hero p{font-size:clamp(16px,2vw,20px);color:#475569;margin:0 auto 26px;max-width:680px}
.hero .btns{display:flex;gap:12px;justify-content:center;flex-wrap:wrap}
.hero .small{color:var(--mute);font-size:14px;margin-top:12px}
.chips{display:flex;flex-wrap:wrap;gap:10px;justify-content:center;margin:34px auto 8px;max-width:900px}
.chip{display:inline-flex;gap:8px;align-items:center;padding:9px 18px;border-radius:999px;background:#fff;border:1px solid var(--line);color:var(--ink);text-decoration:none;font-weight:500}
.chip span{color:#94a3b8}
.chip:hover{border-color:#c7d2fe}

/* sections + grid */
.sec{padding:30px 0}
.sec h2{text-align:center;font-size:clamp(24px,3vw,34px);letter-spacing:-.02em;margin:0 0 8px}
.sec .lead{text-align:center;color:var(--mute);max-width:720px;margin:0 auto 26px}
.grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
@media (max-width:1000px){.grid{grid-template-columns:repeat(3,1fr)}}
@media (max-width:700px){.grid{grid-template-columns:repeat(2,1fr);gap:12px}}
.card{display:flex;flex-direction:column;align-items:center;text-align:center;background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:26px 16px 22px;text-decoration:none;color:var(--ink);transition:box-shadow .15s,transform .15s}
.card:hover{box-shadow:0 10px 28px rgba(15,23,42,.08);transform:translateY(-2px)}
.card img{width:72%;aspect-ratio:1;object-fit:contain;margin-bottom:16px}
.card b{font-weight:500;font-size:17px;line-height:1.3}
.card small{color:#94a3b8;font:600 12px ui-monospace,Menlo,monospace;letter-spacing:.04em;margin-top:6px}
@media (max-width:700px){.card{padding:16px 10px}.card b{font-size:14px}}

/* article */
.crumbs{font-size:14px;color:var(--mute);padding:20px 0 0}
.crumbs a{color:var(--mute)}
.sign{display:grid;grid-template-columns:minmax(0,420px) 1fr;gap:40px;align-items:start;padding:20px 0 10px}
@media (max-width:820px){.sign{grid-template-columns:1fr;gap:18px}}
.sign .pic{background:#fff;border:1px solid var(--line);border-radius:22px;padding:34px;display:flex;justify-content:center}
.sign .pic img{width:100%;max-width:340px;aspect-ratio:1;object-fit:contain}
.sign h1{font-size:clamp(26px,3.6vw,40px);letter-spacing:-.025em;line-height:1.15;margin:4px 0 10px}
.tag{display:inline-block;font:600 12px/1 ui-monospace,Menlo,monospace;padding:6px 10px;border-radius:8px;background:var(--soft);color:var(--pri);letter-spacing:.04em}
.box{background:#fff;border:1px solid var(--line);border-radius:var(--r);padding:20px 22px;margin:16px 0}
.box h2{font-size:18px;margin:0 0 6px}
.box p{margin:0;color:#334155}
.tr{display:grid;grid-template-columns:auto 1fr;gap:6px 14px;font-size:15px;color:#334155}
.tr dt{color:var(--mute);font-weight:600}
.tr dd{margin:0}
.pn{display:flex;justify-content:space-between;gap:10px;margin:8px 0 0;flex-wrap:wrap}
.pn a{color:var(--mute);text-decoration:none;font-size:15px}
.prose{max-width:820px;margin:0 auto}
.prose h2{text-align:left}
.faq details{background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px 20px;margin:10px 0}
.faq summary{cursor:pointer;font-weight:600;font-size:17px;list-style:none;display:flex;justify-content:space-between;gap:10px}
.faq summary::after{content:"⌄";color:var(--mute)}
.faq details[open] summary::after{content:"⌃"}
.faq details p{margin:10px 0 0;color:#334155}

/* test */
.panel{background:#fff;border:1px solid var(--line);border-radius:22px;padding:26px;max-width:820px;margin:0 auto}
.panel h3{margin:22px 0 12px;font-size:19px}
.panel h3:first-child{margin-top:0}
.opts2{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.opt{font:inherit;font-weight:500;padding:16px;border-radius:14px;border:1px solid var(--line);background:#fff;color:var(--ink);cursor:pointer;text-align:left}
.opt[aria-pressed=true]{background:var(--soft);border-color:var(--pri2);color:var(--pri);box-shadow:0 0 0 1px var(--pri2)}
.opt span{color:#94a3b8;margin-left:6px}
.opt.c{text-align:center}
@media (max-width:600px){.opts2{grid-template-columns:1fr}}
.row{display:flex;gap:10px;flex-wrap:wrap}
.row .opt{flex:1;min-width:90px;text-align:center;padding:12px}
select.opt{appearance:auto}
.go{margin-top:24px;width:100%}
.bar{height:8px;background:#eef1f6;border-radius:9px;overflow:hidden;margin-bottom:18px}
.bar i{display:block;height:100%;background:var(--pri2);width:0;transition:width .3s}
.qhead{display:flex;justify-content:space-between;color:var(--mute);font-size:14px;margin-bottom:8px}
.q{text-align:center}
.q h2{font-size:22px;margin:0 0 6px}
.big{width:min(60vw,260px,42vh);aspect-ratio:1;object-fit:contain;margin:10px auto 18px;display:block}
.answers{display:grid;gap:10px;margin-top:8px}
.answers.pics{grid-template-columns:1fr 1fr}
.ans{font:inherit;text-align:left;padding:14px 16px;border-radius:14px;border:1px solid var(--line);background:#fff;color:var(--ink);cursor:pointer}
.ans:hover:not(:disabled){border-color:#b9c6e8}
.ans small{display:block;color:var(--mute)}
.ans img{width:100%;aspect-ratio:1;object-fit:contain;display:block}
.ans.ok{border-color:var(--ok);background:#f0fdf4}
.ans.bad{border-color:var(--bad);background:#fef2f2}
.explain{margin-top:14px;text-align:left;background:#f8fafc;border-radius:14px;padding:14px 16px;color:#334155;display:none}
.explain.show{display:block}
.next{margin-top:16px;width:100%}
.flash{min-height:420px;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;cursor:pointer;user-select:none}
.flash .hid{display:none}
.flash.open .hid{display:block}
.flash.open .tap{display:none}
.tap{color:var(--mute);font-size:14px}
.result{text-align:center}
.result .score{font-size:56px;font-weight:800;letter-spacing:-.03em}
.miss{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:10px;margin:16px 0;text-align:left}
.miss a{border:1px solid var(--line);border-radius:12px;padding:10px;font-size:13px;color:var(--ink);text-decoration:none;background:#fff}
.miss img{width:56px;height:56px;object-fit:contain;display:block;margin-bottom:6px}
.wa{background:linear-gradient(180deg,#25d366,#1ebe57);box-shadow:0 2px 6px rgba(30,190,87,.3)}
.switch{display:flex;align-items:center;justify-content:center;gap:12px;margin-top:18px;color:#334155;cursor:pointer}
.switch input{width:46px;height:26px;appearance:none;background:#e2e8f0;border-radius:99px;position:relative;cursor:pointer;transition:background .2s}
.switch input::after{content:"";position:absolute;top:3px;left:3px;width:20px;height:20px;border-radius:50%;background:#fff;box-shadow:0 1px 3px rgba(0,0,0,.2);transition:left .2s}
.switch input:checked{background:var(--pri2)}
.switch input:checked::after{left:23px}

.ad{margin:22px auto;max-width:var(--max)}
footer{border-top:1px solid var(--line);background:#fff;margin-top:40px}
footer .wrap{padding:26px 16px;display:flex;flex-wrap:wrap;gap:10px 24px;justify-content:space-between;color:var(--mute);font-size:14px}
footer a{color:var(--mute)}

/* language switcher */
.lang{position:relative;flex:none}
.lang summary{list-style:none;cursor:pointer;padding:8px 12px;border-radius:10px;border:1px solid var(--line);font-weight:600;font-size:14px;color:#334155;white-space:nowrap;background:#fff}
.lang summary::-webkit-details-marker{display:none}
.lang[open] summary{border-color:var(--pri2);color:var(--pri)}
.lang div{position:absolute;right:0;top:calc(100% + 6px);background:#fff;border:1px solid var(--line);border-radius:12px;box-shadow:0 10px 28px rgba(15,23,42,.12);padding:6px;min-width:150px;z-index:30;display:flex;flex-direction:column}
.lang a{padding:9px 12px;border-radius:8px;color:var(--ink);text-decoration:none}
.lang a:hover{background:#f1f5f9}
.lang a[aria-current]{background:var(--soft);color:var(--pri);font-weight:600}
@media (max-width:1100px){.top .cta{display:none}}
@media (max-width:820px){.lang{margin-left:auto}.burger{margin-left:0}}
.card i{font-style:normal;color:var(--mute);font-size:13px;margin-top:4px;line-height:1.3}
.box.es{background:var(--soft);border-color:transparent}
.box.es p{font-size:19px;letter-spacing:.01em}