:root{font-family:system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;color:#203129;background:#f4f6f0;font-size:18px;line-height:1.6;--green:#24683f;--green-dark:#184f2e;--line:#dce5d9;--muted:#5f6d63}
*{box-sizing:border-box}
body{margin:0;min-width:360px}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.skip{position:absolute;left:-999px;top:8px;background:#fff;padding:8px 12px;border-radius:8px;z-index:10}
.skip:focus{left:8px}
header{display:flex;align-items:center;gap:14px;flex-wrap:wrap;max-width:900px;margin:auto;padding:20px}
.brand{font-weight:850;letter-spacing:.09em;color:#215c3d}
header>span+span{color:var(--muted)}
.lang{margin-left:auto}
main{background:#fff;max-width:790px;margin:0 auto;padding:36px;border:1px solid var(--line);border-radius:20px;min-height:300px}
main:focus{outline:none}
h1{font-size:clamp(1.6rem,5vw,2.3rem);line-height:1.18;letter-spacing:-.02em;margin:6px 0 22px}
h1:focus{outline:none}
h2{font-size:1.25rem;line-height:1.35;margin:26px 0 10px}
h3{font-size:1.05rem;margin:20px 0 8px}
.kicker{text-transform:uppercase;letter-spacing:.09em;color:#3a684e;font-size:.72rem;font-weight:700;margin:0}
p{margin:14px 0}
.muted,footer{color:var(--muted);font-size:.88rem}
.notice{padding:14px 16px;background:#f2f5ee;border-radius:10px;font-size:.92rem}
.who{max-width:790px;margin:0 auto 14px;padding:12px 18px;background:#fff8e6;border:1px solid #efd9a0;border-radius:12px;display:flex;gap:12px;align-items:center;flex-wrap:wrap}
.who strong{font-size:1.1rem}
blockquote{border-left:4px solid #36895e;background:#eff7f0;padding:10px 18px;margin:20px 0;border-radius:0 10px 10px 0}
blockquote p{margin:8px 0}
ul,ol{padding-left:26px}
li{margin:6px 0}
code{background:#eef2ea;padding:1px 5px;border-radius:5px;font-size:.92em}
button{font:inherit;line-height:1.3;border:0;background:var(--green);color:#fff;border-radius:10px;padding:14px 22px;min-height:48px;cursor:pointer;margin:8px 8px 8px 0}
button:hover{background:var(--green-dark)}
button:disabled{opacity:.6;cursor:wait}
button.secondary{background:#eaf0e7;color:#24442f}
button.secondary:hover{background:#dae6d6}
button.link{background:none;color:#a02121;padding:6px 8px;min-height:36px;text-decoration:underline}
.actions{display:flex;flex-wrap:wrap;margin-top:22px}
progress{width:100%;height:8px;accent-color:var(--green)}
fieldset{padding:16px;border:1px solid var(--line);border-radius:12px;margin:22px 0;min-width:0}
legend{font-weight:650;line-height:1.4;padding:0 8px;max-width:100%;overflow-wrap:anywhere}
label.opt{display:flex;gap:12px;align-items:flex-start;border-radius:8px;padding:12px;cursor:pointer}
label.opt:hover{background:#eff4eb}
label.opt:has(input:checked){background:#e4f1e4}
input[type=radio],input[type=checkbox]{margin-top:7px;accent-color:var(--green);flex-shrink:0;width:20px;height:20px}
select{font:inherit;border:1px solid #c5d5c7;border-radius:9px;padding:8px;background:#fff;color:#24442f;min-height:44px}
a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid #1d4ed8;outline-offset:3px}
img.illustration{display:block;width:100%;height:auto;max-height:260px;object-fit:contain;border-radius:10px;background:#fcf8ed;margin:10px 0 16px}
.result{padding:18px;border-radius:12px;margin:18px 0}
.result.passed{background:#e4f1e4;border:1px solid #9ccaa8}
.result.failed{background:#fff1ec;border:1px solid #f0b8a6}
.feedback{list-style:none;padding:0}
.feedback li{padding:12px 14px;border:1px solid var(--line);border-radius:10px;margin:10px 0}
.feedback .ok{color:#1d6a3a;font-weight:650}
.feedback .bad{color:#a02121;font-weight:650}
#error{max-width:790px;margin:14px auto;padding:0 22px;color:#a02121}
#error:empty{display:none}
footer{text-align:center;padding:24px}
details{border-top:1px solid var(--line);padding:12px 0;font-size:.92rem}
summary{cursor:pointer}
.lesson-list{list-style:none;padding:0}
.lesson-list li{display:flex;gap:10px;align-items:center;padding:8px 0;border-bottom:1px solid var(--line)}
.lesson-list .done{color:#1d6a3a}
@media (max-width:600px){
  header{padding:14px;gap:10px}
  main{padding:22px 16px;border-radius:14px;margin:0 8px}
  .who{margin:0 8px 12px}
  button{width:100%;margin-right:0}
  header button{width:auto}
  fieldset{padding:12px 6px}
  label.opt{padding:12px 8px}
}
@media (prefers-reduced-motion:no-preference){button{transition:background .15s}}