/* 摸底页 (PY-458)，三学段共用。 */
#placement-app {max-width:760px;margin:0 auto;padding:8px 0 56px;outline:none}
#placement-app h1 {font-size:26px;margin:12px 0 8px}
#placement-app h2 {font-size:18px;margin:0 0 8px}
.pl-lead,.pl-note,.pl-rules {color:var(--muted);font-size:15px;line-height:1.7}
.pl-rules {padding-left:20px;margin:8px 0 16px}
.pl-chapter,.pl-q {border:1px solid var(--line);border-radius:var(--radius);background:var(--card);padding:12px 14px;margin:0 0 12px;min-width:0}
.pl-chapter legend,.pl-q legend {font-weight:700;font-size:15px;padding:0 6px}
.pl-sections {display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:2px 12px}
.pl-check,.pl-opt {display:flex;align-items:flex-start;gap:9px;min-height:44px;padding:9px 8px;font-size:15px;line-height:1.6;cursor:pointer;border-radius:8px;min-width:0}
.pl-check input,.pl-opt input {flex:none;width:18px;height:18px;margin:3px 0 0;accent-color:var(--a)}
.pl-opt span {min-width:0;overflow-wrap:anywhere}
.pl-opt:hover,.pl-check:hover {background:var(--ok-soft)}
.pl-dk {border-top:1px dashed var(--line);border-radius:0;margin-top:4px;color:var(--muted)}
.pl-prompt {font-size:16px;line-height:1.75;margin:4px 0 8px;overflow-wrap:anywhere}
.pl-prompt .katex-display,.pl-opt .katex-display,.pl-fb .katex-display {overflow-x:auto;overflow-y:hidden}
.pl-actions {display:flex;flex-wrap:wrap;gap:10px;margin:16px 0}
.pl-btn {display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:9px 20px;border:1px solid var(--a);border-radius:10px;background:var(--a);color:var(--card);font:inherit;font-size:15px;font-weight:700;text-decoration:none;cursor:pointer}
.pl-btn.ghost {background:transparent;color:var(--fg);border-color:var(--line)}
.pl-btn:focus-visible,.pl-check input:focus-visible,.pl-opt input:focus-visible {outline:3px solid var(--a);outline-offset:2px}
.pl-warn {color:var(--no);font-size:15px;font-weight:600}
.pl-results {list-style:none;margin:12px 0;padding:0}
.pl-row {display:flex;justify-content:space-between;align-items:center;gap:12px;padding:12px 14px;border:1px solid var(--line);border-radius:10px;background:var(--card);margin-bottom:8px}
.pl-name {min-width:0;font-size:15px;font-weight:600}
.pl-state {flex:none;display:inline-flex;align-items:center;gap:6px;font-size:14px;font-weight:700;padding:3px 10px;border-radius:999px;border:1px solid currentColor}
.pl-state em {font-style:normal;font-weight:500}
.pl-basic {color:var(--a)}
.pl-rusty {color:var(--b)}
.pl-not-yet {color:var(--no)}
.pl-not-learned,.pl-untested {color:var(--muted);border-style:dashed}
.pl-box {border:1px solid var(--line);border-radius:var(--radius);background:var(--card);padding:14px 16px;margin:14px 0}
.pl-path {margin:0;padding-left:22px;font-size:15px;line-height:2}
.pl-path a {color:var(--c);font-weight:600}
.pl-fb {border-top:1px solid var(--line);padding:8px 0;font-size:15px;line-height:1.7;overflow-wrap:anywhere}
.pl-fb summary {cursor:pointer;font-weight:600;min-height:32px}
.pl-fb summary small {display:block;color:var(--muted);font-size:14px;font-weight:400}
.pl-book {margin:0 0 18px}
.pl-book h2 {margin:0 0 6px}
.pl-book h2 .pl-check {font-size:17px;font-weight:700}
.pl-more summary {cursor:pointer;color:var(--muted);font-size:14px;min-height:32px;padding:4px 8px}
.pl-more summary:focus-visible {outline:3px solid var(--a);outline-offset:2px}
.pl-result-book {margin:18px 0}
.pl-box h3 {font-size:16px;margin:14px 0 4px}
.pl-parent {border-left:4px solid var(--b);background:var(--card);border-radius:8px;padding:10px 12px;margin:10px 0;font-size:15px;line-height:1.7}
.pl-opt-row {display:flex;align-items:flex-start;gap:8px;min-width:0}
.pl-opt-row > .pl-opt,.pl-opt-row > .pl-prompt {flex:1 1 auto;min-width:0}
.pl-say {flex:none;display:inline-flex;align-items:center;justify-content:center;width:44px;height:44px;padding:0;border:1.5px solid var(--a);border-radius:50%;background:var(--card);color:var(--a);cursor:pointer}
.pl-say:hover,.pl-say.on {background:var(--a);color:var(--card)}
.pl-say:focus-visible {outline:3px solid var(--a);outline-offset:2px}
body[data-stage="primary"] .pl-more summary,body[data-stage="primary"] .pl-fb summary {display:list-item;box-sizing:border-box;min-height:44px;padding:10px 8px}
body[data-stage="primary"] .pl-path a {display:inline-flex;align-items:center;min-height:44px}