/* Olympiad practice sheets: class chips, page jump, on-screen timed practice */
.op-cls .chip{min-width:44px;justify-content:center}
.op-hint{margin:-6px 0 4px}
.op-hint2{margin:10px 0 0}
.op-jump{display:flex;flex-wrap:wrap;gap:8px;margin-top:10px}
.op-jump .chip{min-height:36px}
.op-practice{margin-top:16px;border:2px solid var(--ink);border-radius:var(--r-sm);background:var(--blue-soft);padding:12px 14px;box-shadow:3px 3px 0 var(--ink)}
.op-practice p{margin:0 0 10px;font-size:14.5px;color:var(--ink)}
.op-hot{background:var(--sun);color:var(--ink)}
.op-quiz{margin-top:28px;border:var(--bw) solid var(--ink);border-radius:var(--r);background:#fff;padding:0 18px 18px;box-shadow:5px 5px 0 var(--ink)}
.op-quiz h2{font-size:21px;margin:16px 0 10px}
.op-bar{position:sticky;top:64px;z-index:5;display:flex;align-items:center;gap:12px;flex-wrap:wrap;background:#fff;border-bottom:2px dashed var(--line);padding:12px 0;margin:0 -2px}
.op-clock{font:800 24px/1 ui-monospace,Consolas,monospace;background:var(--ink);color:#fff;border-radius:10px;padding:8px 12px;min-width:94px;text-align:center}
.op-clock.op-low{background:var(--err)}
.op-count{font-weight:700;font-size:14px;color:var(--ink-2);flex:1}
.op-bar .btn{padding:9px 16px}
.op-done .op-bar .btn{display:none}
.op-qs{list-style:none;margin:0;padding:0}
.op-sec{font-weight:800;font-size:13px;letter-spacing:.06em;text-transform:uppercase;color:#fff;background:var(--ink);border-radius:8px;padding:6px 12px;margin:14px 0 8px}
.op-q{border-bottom:1.5px solid var(--line);padding:12px 0}
.op-q fieldset{border:0;margin:0;padding:0;min-width:0}
.op-q legend{font-weight:600;font-size:16px;line-height:1.45;padding:0;margin-bottom:8px;color:var(--ink)}
.op-n{font-weight:800;color:var(--ink-2)}
.op-fig{margin:2px 0 10px}
.op-fig svg{max-width:100%;height:auto;border:1.5px solid var(--line);border-radius:10px;background:#fff}
.op-opts{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}
.op-figs{grid-template-columns:repeat(4,minmax(0,170px))}
.op-opt{display:flex;align-items:center;gap:8px;min-height:44px;border:2px solid var(--ink);border-radius:10px;padding:6px 10px;cursor:pointer;background:#fff;font-size:15px;font-weight:600}
.op-opt input{width:18px;height:18px;margin:0;accent-color:var(--ink);flex:none}
.op-opt:has(input:checked){background:var(--blue-soft)}
.op-l{font-weight:800;color:var(--ink-2)}
.op-ofig{flex-direction:column;align-items:flex-start;gap:2px;padding:6px}
.op-ofig svg{width:100%;height:auto}
.op-ofig .op-l{display:flex;gap:6px;align-items:center}
.op-why{margin-top:8px;font-size:14px;line-height:1.5;color:var(--ink-2);background:var(--soft);border-radius:10px;padding:8px 10px}
.op-right .op-why{background:#e3f6ea}
.op-wrong .op-why{background:#fdecec}
.op-opt.op-ans{border-color:var(--ok);background:#e3f6ea}
.op-wrong .op-opt:has(input:checked){border-color:var(--err);background:#fdecec}
.op-result:empty{display:none}
.op-result{margin-bottom:8px}
@media (max-width:560px){.op-figs{grid-template-columns:repeat(2,minmax(0,1fr))}.op-quiz{padding:0 12px 14px}.op-clock{font-size:20px;min-width:80px}}