:root {
  --brand: #1e40af;
  --border: #dcdcdc;
  --grey: #555;
  --gap: 1.4rem;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: system-ui, sans-serif; line-height: 1.6; color: #222; }
main { max-width: 760px; margin: auto; padding: 2rem 1rem; }
h1, h2 { margin-bottom: .6rem; line-height: 1.25; }
p { margin: .4rem 0 1rem; }
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }

/* Calculator form */
.mhc-calculator {
  display: grid; gap: var(--gap); margin: 1.5rem 0;
}
.mhc-calculator label {
  display: flex; justify-content: space-between; align-items: center;
  font-weight: 500; color: var(--grey);
}
.mhc-calculator label span { flex: 1 1 55%; }
.mhc-calculator input {
  flex: 0 0 40%; padding: .5rem; border: 1px solid var(--border); border-radius: 4px;
  font: inherit;
}
.mhc-calculator button {
  padding: .6rem 1.2rem; border: 0; border-radius: 4px;
  background: var(--brand); color: #fff; font-weight: 600; cursor: pointer;
}
.mhc-calculator button:hover { background: darken(var(--brand),10%); }
.mhc-error { color: #d00; margin: 0; font-size: .9rem; }
.mhc-result { margin-top: 1rem; font-weight: 700; font-size: 1.1rem; }

/* Core & Outer */
.core-section, .outer-sections, .related-calculators, .faq {
  margin: 2rem 0;
}
.outer-sections article { margin-bottom: 1.5rem; }

/* E-A-V table */
.eav-table {
  width: 100%; border-collapse: collapse; margin: 1.5rem 0;
}
.eav-table th, .eav-table td {
  border: 1px solid var(--border); padding: .5rem; text-align: left;
}

/* FAQ */
details {
  margin: 1rem 0; border: 1px solid var(--border); border-radius: 4px; padding: .6rem;
}
summary { font-weight: 600; cursor: pointer; }
summary:focus { outline: 2px solid var(--brand); }