.challenge-intro{padding:70px 0 40px}.challenge-intro h1{font-size:clamp(42px,6vw,76px);line-height:1.08;margin:18px 0}.challenge-intro>p{max-width:700px;line-height:1.8;color:var(--muted)}.challenge-intro em{color:var(--orange)}.challenge-timeline{display:flex;gap:16px;flex-wrap:wrap;margin:28px 0}.challenge-timeline>span{padding:14px 20px;border:1px solid var(--line);border-radius:14px;background:var(--panel)}.challenge-block{margin:45px 0}.challenge-block-heading{display:flex;justify-content:space-between;align-items:start;gap:20px;margin-bottom:24px}.challenge-block-heading h2{font-size:30px}.challenge-block-heading p{font-size:13px;color:var(--muted);margin-top:8px}.challenge-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.challenge-card{position:relative;min-width:0;padding:26px;background:var(--panel);border:1px solid var(--line);border-radius:22px;box-shadow:0 18px 40px #00000012}.challenge-card.is-solved{border-color:#65bb9a}.challenge-card-top{display:flex;justify-content:space-between;align-items:start;gap:12px}.challenge-card-top .eyebrow{font-size:10px;letter-spacing:.1em}.challenge-points{white-space:nowrap;font-size:12px;color:var(--orange)}.challenge-card h3{font-size:23px;line-height:1.35;margin:22px 0 12px}.challenge-card p{font-size:13px;line-height:1.8;margin:12px 0}.challenge-card pre{background:var(--bg);border:1px solid var(--line);border-radius:12px;padding:18px;overflow:auto;max-width:100%;font:13px/1.7 Consolas,monospace;margin:20px 0;tab-size:4}.challenge-answer label{display:block;font-size:13px}.challenge-answer input{display:block;background:var(--bg);border:1px solid var(--line);border-radius:10px;color:var(--text);padding:12px;width:100%;margin:8px 0 14px}.challenge-answer .button{font-size:12px;padding:14px 18px}.challenge-feedback{color:var(--orange);overflow-wrap:anywhere}.challenge-ranking-panel{padding:30px;border:1px solid var(--line);border-radius:22px;background:var(--panel)}.challenge-rank-tabs{display:flex;flex-wrap:wrap;gap:10px;margin:20px 0}.challenge-rank-tabs button,.challenge-small-button{padding:12px 16px;border:1px solid var(--line);border-radius:10px;background:var(--bg);color:var(--text);font:inherit;font-size:12px}.challenge-rank-tabs [aria-pressed=true]{background:var(--orange);color:#14213a;border-color:var(--orange)}.challenge-ranking{list-style:none;margin:0;padding:0}.challenge-ranking li{display:flex;gap:16px;padding:17px 0;border-top:1px solid var(--line);align-items:center}.rank-position{color:var(--orange);min-width:22px}.rank-score{margin-left:auto;font-size:13px;color:var(--muted)}.rank-self strong{color:var(--orange)}.challenge-rules{padding:25px;border-left:2px solid var(--orange);margin:30px 0 60px;color:var(--muted);line-height:1.9;font-size:14px}.challenge-rules p{margin:8px 0}.challenge-checklist{list-style:none;padding:0;margin:20px 0}.challenge-checklist li{display:flex;gap:14px;padding:16px 0;border-top:1px solid var(--line)}.challenge-checklist li>span{font-size:24px;color:var(--orange)}.challenge-checklist p{font-size:12px;line-height:1.8;color:var(--muted);margin:8px 0}.challenge-history-nav{display:flex;gap:16px;align-items:center;flex-wrap:wrap;font-size:12px}.nav-challenges{color:var(--orange)!important}
@media(max-width:1100px){.challenge-grid{grid-template-columns:1fr}.challenge-intro{padding-top:40px}}
@media(max-width:500px){.challenge-card,.challenge-ranking-panel{padding:20px}.challenge-block-heading{flex-direction:column}.challenge-ranking li{gap:10px;flex-wrap:wrap}.rank-score{width:100%;margin-left:32px}.challenge-card-top{flex-wrap:wrap}}

.challenge-subject-picker{margin:28px 0;max-width:540px}.challenge-subject-picker label{display:block;font-weight:650;font-size:14px}.challenge-subject-picker select{display:block;margin-top:10px;width:100%;padding:14px;border:1px solid var(--line);border-radius:12px;color:var(--text);background:var(--panel);font:inherit;font-size:14px}.challenge-subject-picker p{font-size:13px;color:var(--muted);margin-top:10px}