:root{color:#17212b;background:#fff7ed;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;--ink: #1c2430;--muted: #6b7280;--panel: #ffffff;--line: #f3c38b;--primary: #e74b2c;--primary-dark: #bd3219;--good: #15945a;--warn: #f59e0b;--danger: #d92d20;--spark: #ffd166;--blue: #2563eb}*{box-sizing:border-box}body{margin:0;min-width:320px;background:radial-gradient(circle at 14% 12%,rgba(255,209,102,.46),transparent 24%),radial-gradient(circle at 86% 8%,rgba(37,99,235,.18),transparent 24%),linear-gradient(135deg,#fff7ed,#fef3c7 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infinite}.eyebrow{margin:0 0 2px;color:var(--primary);font-size:.75rem;font-weight:800;letter-spacing:0;text-transform:uppercase}h1,h2,p{margin-top:0}h1{margin-bottom:0;font-size:clamp(1.75rem,3vw,2.8rem);line-height:1;letter-spacing:0;text-shadow:0 4px 0 rgba(255,209,102,.55)}.topbar-stats{display:grid;grid-template-columns:repeat(3,minmax(120px,1fr));gap:10px}.stat{min-height:64px;padding:11px 12px;border:1px solid var(--line);border-radius:8px;background:#ffffffd1;box-shadow:0 8px #e74b2c14}.arena-banner{position:relative;display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:18px;max-width:1180px;min-height:86px;margin:0 auto 16px;padding:18px 22px;border:2px solid #1c2430;border-radius:8px;color:#fff;background:linear-gradient(90deg,#1c2430eb,#e74b2ce6),repeating-linear-gradient(135deg,transparent 0 12px,rgba(255,255,255,.12) 12px 24px);box-shadow:0 14px #1c243024;overflow:hidden}.arena-banner .eyebrow{color:#ffd166}.arena-banner strong{display:block;margin-top:4px;font-size:clamp(1rem,2vw,1.35rem)}.arena-pulse{position:absolute;inset:-80px auto auto 50%;width:160px;height:160px;border:3px solid rgba(255,255,255,.28);border-radius:50%;transform:translate(-50%);animation:pulse-ring 1.7s ease-out infinite}.versus-chip{position:relative;z-index:1;display:inline-flex;align-items:center;justify-content:center;gap:7px;min-width:92px;min-height:44px;border:2px solid #1c2430;border-radius:999px;color:#1c2430;background:#ffd166;font-size:1.2rem;font-weight:1000;box-shadow:0 6px #1c24303d;animation:versus-bounce 1.9s ease-in-out infinite}.stat span,.result-list dt{display:block;color:var(--muted);font-size:.72rem;font-weight:800;letter-spacing:0;text-transform:uppercase}.stat strong{display:block;margin-top:5px;color:var(--ink);font-size:.95rem}.battle-grid{display:grid;grid-template-columns:minmax(0,1.25fr) minmax(320px,.75fr);gap:16px;max-width:1180px;margin:0 auto}.panel{border:2px solid 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0%,rgba(37,99,235,.2),transparent 32%)}.upcoming-title{margin-bottom:14px;color:var(--ink);font-size:1.45rem;font-weight:900;line-height:1.15}.victory-burst{display:flex;gap:8px;margin-bottom:12px}.victory-burst span{display:block;width:34px;height:10px;border-radius:999px;background:var(--spark);animation:confetti-swipe .9s ease-in-out infinite alternate}.victory-burst span:nth-child(2){background:var(--primary);animation-delay:.12s}.victory-burst span:nth-child(3){background:var(--blue);animation-delay:.24s}@keyframes grid-drift{0%{background-position:0 0,0 12px}to{background-position:48px 48px,-48px 60px}}@keyframes badge-pop{0%,to{transform:rotate(-5deg) scale(1)}50%{transform:rotate(4deg) scale(1.06)}}@keyframes launch-glow{0%,to{filter:saturate(1)}50%{filter:saturate(1.35) brightness(1.08)}}@keyframes timer-heat{0%,to{box-shadow:inset 0 0 0 8px #ffd16638,0 0 #e74b2c00}50%{box-shadow:inset 0 0 0 8px #ffd16657,0 0 32px #e74b2c52}}@keyframes pulse-ring{0%{opacity:.1;transform:translate(-50%) scale(.72)}60%{opacity:.62}to{opacity:0;transform:translate(-50%) scale(1.5)}}@keyframes versus-bounce{0%,to{transform:translateY(0) rotate(-2deg)}50%{transform:translateY(-4px) rotate(2deg)}}@keyframes score-pop{0%{opacity:0;transform:scale(.84)}to{opacity:1;transform:scale(1)}}@keyframes confetti-swipe{0%{transform:translate(0) rotate(-7deg)}to{transform:translate(12px) rotate(7deg)}}@media(max-width:900px){.topbar{align-items:flex-start;flex-direction:column}.topbar-stats,.battle-grid{width:100%;grid-template-columns:1fr}.arena-banner{grid-template-columns:1fr}.versus-chip{justify-self:start}}@media(max-width:560px){.app-shell{padding:14px}.topbar-stats,.button-row{grid-template-columns:1fr}.problem-panel,.timer-panel,.result-panel,.upcoming-panel{padding:16px}}