body {
  margin: 0;
  padding: 32px 16px;
  background: white;
  color: #222;
  font-family: Arial, sans-serif;
  line-height: 1.4;
}

main {
  max-width: 720px;
  margin: 0 auto;
}

h1 {
  margin-top: 0;
  font-size: 1.75rem;
}

label {
  display: block;
  margin-bottom: 6px;
  font-weight: bold;
}

select {
  width: 100%;
  max-width: 420px;
  padding: 8px;
  font: inherit;
}

.formula,
.note {
  color: #555;
}

.table-wrapper {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th,
td {
  padding: 8px 10px;
  border: 1px solid #ccc;
  text-align: left;
}

th {
  background: #f3f3f3;
}

tbody tr:nth-child(even) {
  background: #fafafa;
}

.note {
  font-size: 0.9rem;
}