.sd-wrap {
  max-width: 760px;
  margin: 18px auto;
  padding: 18px;
  border-radius: 12px;
  background: #fff;
  border: 1px solid #e6e6e6;
  font-family: system-ui, Segoe UI, Roboto, Arial, sans-serif;
}

.sd-row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 10px 0;
  flex-wrap: wrap;
}

.sd-row label {
  min-width: 160px;
  font-weight: 600;
}

.sd-row input[type="text"],
.sd-row input[type="email"],
.sd-row input[type="number"],
.sd-row select {
  flex: 1;
  padding: 8px;
  border: 1px solid #d1d5db;
  border-radius: 8px;
}

.sd-options {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  border: 0;
  padding: 6px 0;
}

.sd-card {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 12px;
  border: 1px solid #e5e7eb;
  border-radius: 10px;
  min-width: 220px;
  cursor: pointer;
}

.sd-card input[type="radio"] {
  margin-top: 4px;
}

.sd-card-body {
  display: block;
}

.sd-card-title {
  font-weight: 700;
}

.sd-card-desc {
  font-size: 13px;
  color: #555;
  margin-top: 6px;
}

.sd-sub {
  font-size: 13px;
  margin-top: 8px;
}

/* === Multi-student checkbox + number field === */
.sd-multi {
  display: flex;
  align-items: center;
  gap: 8px; /* space between text and number box */
}

.sd-multi label {
  display: inline-flex;
  align-items: center;
  gap: 4px; /* space between checkbox and text */
  margin: 0;
  padding: 0;
  font-weight: normal;
}

.sd-multi input[type="checkbox"] {
  margin: 0;
}

.sd-multi input[type="number"] {
  width: 60px;   /* adjust width */
  padding: 6px;
}

.sd-hidden {
  display: none;
}

/* === Summary + Button === */
.sd-summary {
  font-weight: 800;
  margin-top: 8px;
}

.sd-btn {
  background: #0b5cff;
  color: #99c9ff;
  border: 0;
  padding: 10px 18px;
  border-radius: 10px;
  font-weight: 700;
  cursor: pointer;
}

.sd-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.sd-unavailable {
  padding: 16px;
  background: #99c9ff;
  border-radius: 8px;
  border: 1px solid #eee;
  text-align: center;
}

/* === Responsive === */
@media (max-width: 600px) {
  .sd-row label {
    min-width: 120px;
  }
  .sd-card {
    min-width: 100%;
  }
}