body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: #121212;
  color: #e0e0e0;
  margin: 0;
  padding: 20px;
}
.container { max-width: 900px; margin: 0 auto; }
header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.card { background: #1e1e1e; padding: 20px; border-radius: 8px; margin-bottom: 20px; }
.badge { padding: 6px 12px; border-radius: 20px; font-weight: bold; font-size: 0.9em; }
.badge.valid { background: #2e7d32; color: #fff; }
.badge.invalid { background: #c62828; color: #fff; }
.btn { padding: 10px 16px; border: none; border-radius: 4px; cursor: pointer; font-weight: bold; }
.btn.primary { background: #ff385c; color: white; }
table { width: 100%; border-collapse: collapse; margin-top: 10px; }
th, td { padding: 10px; text-align: left; border-bottom: 1px solid #333; }