@import url('/site-shell.css');
:root{--navy:#0b2a5b;--navy-2:#1d4a80;--teal:#0a9aa6;--teal-ink:#08707a;--teal-50:#e6f5f6;--ink:#16202c;--ink-2:#3b4a5c;--muted:#5b6a7c;--line:#e3e8ee;--bg:#fff;--soft:#f5f7fa;font-family:"Segoe UI Variable Text","Segoe UI",system-ui,-apple-system,Roboto,Arial,sans-serif;font-size:16px;line-height:1.65;color:var(--ink);background:var(--bg)}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);-webkit-font-smoothing:antialiased}
a{color:var(--navy-2);text-underline-offset:2px}
.skip-link{position:fixed;left:12px;top:-80px;z-index:50;background:#fff;padding:10px 14px;border:2px solid var(--teal);border-radius:8px}
.skip-link:focus{top:10px}
.learn-page{max-width:1180px;margin:auto;padding:34px 20px 50px;color:#17314e}
.learn-boundary{margin:0 0 22px;padding:0 0 12px;border:solid var(--rule);border-width:0 0 1px;background:none;font-size:14px;line-height:1.6}
.practice{max-width:860px;border:1px solid var(--rule);border-radius:6px;padding:22px;background:#fff}
[hidden]{display:none!important}
.practice h2{font-size:23px;line-height:1.4;margin:12px 0}
.practice p{line-height:1.6}
.mode-bar,.learn-actions{display:flex;gap:10px;flex-wrap:wrap}
.practice button{min-height:44px;padding:10px 15px;border:1px solid var(--btn-line);border-radius:4px;background:#fff;color:#0b2a5b;font:600 15px system-ui;cursor:pointer}
.practice button.primary{background:#0b2a5b;color:#fff;border-color:#0b2a5b}
.mode-bar button[aria-pressed=true]{background:var(--navy-50);border-color:var(--navy);box-shadow:inset 0 0 0 1px var(--navy)}
.practice button:disabled{opacity:.5;cursor:default}
.mode-help,.question-count{font-size:14px;color:#52677a}
.choices{display:grid;gap:10px;margin:16px 0}
.choices label{display:flex;align-items:center;gap:12px;min-height:44px;padding:13px;border:1px solid var(--rule);border-radius:4px;cursor:pointer;line-height:1.5}
.choices label:has(input:checked){background:var(--navy-50);border-color:var(--navy)}
.choices input,.save-choice input{width:19px;height:19px;flex:0 0 19px;accent-color:#0b2a5b}
.practice fieldset{border:0;padding:0;margin:0;min-width:0}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.feedback{margin:20px 0 0;padding:18px;background:var(--panel);border:1px solid var(--rule);border-radius:4px;line-height:1.6}
.feedback h3{margin:0 0 8px;font-size:19px}
.feedback p{margin:8px 0}
.feedback a{color:var(--navy-2);text-underline-offset:3px}
.feedback ul{padding-left:20px;font-size:13px}
.score{font-size:25px;font-weight:700}
.practice-records{border-top:1px solid #dce4ec;margin-top:28px;padding-top:18px}
.practice-records h2{font-size:18px}
.save-choice{display:flex;gap:10px;align-items:center;min-height:44px}
.records-note{font-size:13px;color:#52677a}
.learn-sources{max-width:860px;margin-top:25px;border:1px solid var(--rule);border-radius:4px;padding:14px 18px;font-size:14px;line-height:1.6}
.learn-sources summary{font-weight:650;cursor:pointer;min-height:44px;display:list-item;align-content:center}
#engine-provenance{overflow-wrap:anywhere;font-size:12px}
#question-strip{margin:20px 0;overflow-x:auto;background:#fff;max-width:100%}
#question-strip svg{display:block;width:100%;height:auto;border:1px solid #e7bab6;border-radius:5px;background:#fff8f7}
#question-strip figcaption{font-size:12px;color:#52677a;margin-top:7px;line-height:1.5}
.learn-grid-minor{stroke:#f5d8d5;stroke-width:.13;fill:none}.learn-grid-major{stroke:#efbcb7;stroke-width:.2;fill:none}
.learn-trace{fill:none;stroke:#163d4a;stroke-width:.4;stroke-linejoin:round}
.learn-lead{font:600 3px system-ui;fill:#34516b}
:focus-visible{outline:3px solid #0a9aa6;outline-offset:3px}
@media(max-width:600px){.learn-page{padding:24px 16px 36px}.practice{padding:16px}.practice h2{font-size:20px}.mode-bar{display:grid;grid-template-columns:1fr}.learn-actions button{flex:1 1 140px}}