#welcome-screen #aiArenaModeBtn{grid-column:1 / -1}
#aiArenaDialog{box-sizing:border-box;width:min(580px,calc(100vw - 24px));max-height:calc(100dvh - 24px);padding:0;border:1px solid #52eff1;border-radius:12px;background:#061326;color:#e7fbff;box-shadow:0 0 36px #00d8ed33;overflow:auto;z-index:25000}
#aiArenaDialog::backdrop{background:rgba(0,5,16,.88)}
.arena-launch-card{padding:clamp(18px,4vw,32px);text-align:center}
#aiArenaTitle{font:clamp(23px,5.4vw,38px)/1.35 TetrisMania,'Arial Black',Impact,sans-serif;margin:0 0 22px;background:linear-gradient(45deg,magenta,cyan,yellow,lime,red);background-size:400%;background-clip:text;-webkit-background-clip:text;-webkit-text-fill-color:transparent;animation:gradientAnimation 5s ease infinite;text-shadow:2px 2px 3px #0008}
#aiArenaPlayers{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.arena-player{min-width:0;padding:14px 10px;border:1px solid #47f8eb66;border-radius:9px;background:#0b2033}
.arena-player:nth-child(2){border-color:#dc67fa88}
.arena-player h3{font:700 13px/1.4 system-ui,sans-serif;color:#b5ff70;margin:0 0 9px}
.arena-player:nth-child(2) h3{color:#f29aff}
.arena-player p{font:12px/1.5 system-ui,sans-serif;overflow-wrap:anywhere;margin:6px 0;color:#d5ecf8}
#aiArenaMessage,#aiArenaSelection{font:13px/1.6 system-ui,sans-serif;margin:16px 0;color:#bedce9}
#aiArenaSelection:empty{display:none}
.arena-launch-actions{display:flex;flex-wrap:wrap;justify-content:center;gap:8px;margin-top:22px}
.arena-launch-actions button{font:700 12px/1.4 system-ui,sans-serif;padding:11px 12px;min-height:44px;border-radius:7px;border:1px solid #50d8e7;background:#11374b;color:#e9fdff;cursor:pointer}
.arena-launch-actions button:focus-visible{outline:2px solid #b7ff72;outline-offset:3px}
.arena-launch-actions button:disabled{opacity:.4;cursor:default}
#aiArenaStart:not(:disabled){background:linear-gradient(115deg,#19615a,#38482b);border-color:#b4ff72}
#aiArenaDialog.arena-introducing .arena-launch-card{animation:arena-introduction .6s ease-out both}
@keyframes arena-introduction{from{transform:scale(.5);opacity:.2;filter:drop-shadow(0 0 20px #e46dff)}to{transform:scale(1);opacity:1;filter:drop-shadow(0 0 8px #63fff0)}}
@media(max-width:420px){#aiArenaPlayers{grid-template-columns:1fr}.arena-launch-actions{flex-direction:column}.arena-launch-actions button{width:100%}}
@media(prefers-reduced-motion:reduce){#aiArenaTitle,#aiArenaDialog.arena-introducing .arena-launch-card{animation:none}}