:root { font-family: system-ui, "Microsoft YaHei", sans-serif; color: #172b4d; background: #f5f8fc; }
body { margin: 0; }
.checkout { max-width: 760px; margin: 32px auto; padding: 28px; background: white; border: 1px solid #dce5f1; border-radius: 18px; }
.back { color: #2364f5; text-decoration: none; }
h1 { font-size: 28px; }
h2 { font-size: 20px; }
#message { min-height: 1.6em; color: #315180; }
.product { border: 1px solid #dce5f1; border-radius: 12px; padding: 18px; margin: 12px 0; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.product p { margin: 6px 0 0; color: #60728e; }
button { background: #2364f5; color: white; border: 0; border-radius: 9px; padding: 10px 18px; cursor: pointer; font: inherit; }
button:disabled { opacity: .5; cursor: wait; }
.code { font-size: 20px; font-weight: 700; letter-spacing: .08em; overflow-wrap: anywhere; }
.actions { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
[hidden] { display: none !important; }
@media (max-width: 600px) { .checkout { margin: 0; border: 0; border-radius: 0; min-height: 100vh; padding: 22px; } .product { display: block; } .product button { margin-top: 12px; } }