body{margin:0;background:#f2f6fd;color:#152647;font:16px/1.55 system-ui,sans-serif}.challenge{max-width:950px;margin:auto;padding:20px}.hero{background:linear-gradient(120deg,#112b60,#275cbd);color:white;border-radius:22px;padding:26px;margin:20px 0}.hero h1{color:white;font-size:clamp(1.7rem,5vw,2.7rem)}.notice{background:#fff3d1;color:#302300;padding:12px;border-radius:10px}.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}.stats>div,.card{background:white;border-radius:16px;padding:18px;box-shadow:0 5px 18px #142a5012}.stats small,.stats strong{display:block}.stats strong{font-size:1.35rem}.card{margin:18px 0}.stock{border-top:1px solid #dbe3f1;padding:14px 0}.stock strong{font-size:1.25rem}button{background:#194b9d;color:white;border:0;border-radius:10px;padding:11px 16px;margin:6px 7px 6px 0;font-weight:700;cursor:pointer}button:disabled{opacity:.45;cursor:not-allowed}input{display:block;padding:10px;border:1px solid #7a8baa;border-radius:8px;max-width:260px;width:90%}a{color:#164b9b}@media(max-width:640px){.stats{grid-template-columns:repeat(2,1fr)}.challenge{padding:12px}}