* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #f0f4ff, #fafafa);
  color: #333;
  line-height: 1.6;
}

header {
  background: #007bff;
  color: #fff;
  text-align: center;
  padding: 25px 10px;
  box-shadow: 0 3px 10px rgba(0,0,0,0.1);
}

main {
  max-width: 1200px;
  margin: 30px auto;
  padding: 0 20px;
}

.card {
  background: #fff;
  padding: 25px;
  border-radius: 14px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
  margin-bottom: 25px;
}

.card h2 {
  border-left: 5px solid #007bff;
  padding-left: 10px;
  margin-bottom: 15px;
  color: #007bff;
}

input, select, textarea {
  width: 100%;
  padding: 10px;
  border: 1px solid #ccc;
  border-radius: 8px;
  font-size: 15px;
}

textarea {
  height: 130px;
  resize: vertical;
  background: #f8f9fa;
}

button {
  border: none;
  padding: 12px 20px;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s ease, transform 0.1s ease;
  margin-top: 10px;
  width: 100%;
  background: #007bff;
  color: #fff;
}

button:hover {
  background: #0056b3;
  transform: translateY(-1px);
}

/* ✅ Checkbox căn trái */
.checkbox-group {
  display: flex;
  justify-content: flex-start;
  align-items: center;
  gap: 10px;
  margin: 10px 0;
}

.checkbox-group input[type="checkbox"] {
  width: 18px;
  height: 18px;
  accent-color: #007bff;
  cursor: pointer;
}

.checkbox-group label {
  margin: 0;
  cursor: pointer;
  color: #333;
}

/* ✅ Ô chi phí */
.cost-box {
  background: #f8f9ff;
  border: 1px solid #cce0ff;
  border-radius: 8px;
  padding: 10px 15px;
  font-size: 15px;
  color: #222;
}

#costDisplay b { color: #007bff; }

.result {
  background: #f1f2f6;
  border: 1px solid #dcdde1;
  border-radius: 8px;
  padding: 12px;
  white-space: pre-line;
  margin-top: 10px;
}

.table {
  width: 100%;
  border-collapse: collapse;
  text-align: center;
}

.table th, .table td {
  border: 1px solid #ddd;
  padding: 8px;
}

.pagination {
  text-align: center;
  margin-top: 10px;
}

.contact {
  list-style: none;
  padding-left: 0;
}

.contact li { margin: 8px 0; }
.contact a { color: #007bff; text-decoration: none; font-weight: bold; }
.contact a:hover { text-decoration: underline; }

.note {
  font-size: 0.9rem;
  color: #777;
  margin-bottom: 10px;
}

@media (max-width: 600px) {
  .form-row { flex-direction: column; }
}