*{margin:0;padding:0;box-sizing:border-box}html,body{height:100%;overflow:hidden;font-family:system-ui,-apple-system,Segoe UI,sans-serif}#sky{position:fixed;inset:0;display:block}#start-prompt{position:fixed;inset:0;display:flex;align-items:center;justify-content:center;color:#fff;font-size:clamp(1.2rem,4vw,2rem);font-weight:600;text-shadow:0 2px 8px rgba(0,0,0,.35);cursor:pointer;user-select:none}#start-prompt.hidden{display:none}
