.activation-code-fields { border: 0; padding: 0; margin: 0; min-width: 0; }
.activation-code-fields legend { font-size: 16px; margin-bottom: 8px; }
.activation-code-parts { display: flex; align-items: center; gap: 12px; }
.activation-code-parts input {
    flex: 1 1 0; min-width: 0; height: 54px;
    font-family: monospace; font-size: 24px; font-weight: 600;
    letter-spacing: 2px; text-align: center; text-transform: uppercase;
}
.activation-code-parts input[aria-invalid="true"] { border-color: #b01824; }
.activation-code-parts input::placeholder { color: #d6dbe1; opacity: 1; font-weight: 400; }
.activation-code-separator { flex: 0 0 auto; font-size: 24px; color: #00437e; }
@media (max-width: 360px) {
    .activation-code-parts { gap: 6px; }
    .activation-code-parts input { font-size: 20px; letter-spacing: 1px; padding: 6px; }
}