.check-result{text-align:center;padding:20px;border-radius:8px;font-size:18px;font-weight:700}
.check-result.valid{background:#e8f5e9;color:#2e7d32}
.check-result.invalid{background:#fce4ec;color:#c62828}
.check-detail{font-size:14px;font-weight:400;margin-top:10px;color:#666}