:root {
  --bg: #f6f7fb;
  --surface: #ffffff;
  --ink: #17212b;
  --muted: #5b6672;
  --brand: #0f766e;
  --brand-dark: #0b5d57;
  --line: #e3e8ee;
  --shadow: 0 1px 3px rgba(20, 40, 60, 0.08);
  --radius: 14px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
}

.wrap {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 20px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(246, 247, 251, 0.9);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-top: 12px;
  padding-bottom: 12px;
}

.brand {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--brand-dark);
  text-decoration: none;
}

.nav {
  display: flex;
  gap: 18px;
  font-size: 0.92rem;
}

.nav a {
  color: var(--muted);
  text-decoration: none;
}

.nav a:hover {
  color: var(--brand);
}

.hero {
  padding: 64px 0 56px;
  text-align: center;
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.78rem;
  color: var(--brand);
  font-weight: 600;
  margin: 0 0 12px;
}

h1 {
  font-size: clamp(2rem, 4.5vw, 3rem);
  line-height: 1.15;
  margin: 0 0 16px;
}

.lede {
  font-size: 1.08rem;
  color: var(--muted);
  max-width: 640px;
  margin: 0 auto 28px;
}

.hero-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.btn {
  display: inline-block;
  background: var(--brand);
  color: #fff;
  font-weight: 600;
  padding: 12px 24px;
  border-radius: 999px;
  text-decoration: none;
  transition: background 0.15s ease;
}

.btn:hover {
  background: var(--brand-dark);
}

.note {
  font-size: 0.85rem;
  color: var(--muted);
}

.disclaimer {
  background: #fff7ed;
  border-top: 1px solid #ffedd5;
  border-bottom: 1px solid #ffedd5;
  padding: 26px 0;
}

.disclaimer h2 {
  font-size: 1.1rem;
  margin: 0 0 8px;
  color: #9a3412;
}

.disclaimer p {
  margin: 0;
  color: #7c3f1a;
  font-size: 0.95rem;
}

section {
  padding: 56px 0;
}

section h2 {
  font-size: clamp(1.6rem, 3vw, 2rem);
  margin: 0 0 12px;
}

.section-intro {
  color: var(--muted);
  margin: 0 0 28px;
  max-width: 680px;
}

.conceptos {
  display: block;
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px 26px;
  margin-bottom: 18px;
}

.card h3 {
  margin: 0 0 10px;
  font-size: 1.2rem;
  color: var(--brand-dark);
}

.card p {
  margin: 0 0 12px;
}

.card p:last-child {
  margin-bottom: 0;
}

.calculadora {
  background: var(--surface);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.calc-form {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 16px;
  margin-bottom: 20px;
}

.calc-form label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.88rem;
  color: var(--muted);
}

.calc-form input {
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  font-size: 1rem;
  color: var(--ink);
  background: var(--bg);
}

.calc-form input:focus {
  outline: 2px solid var(--brand);
  border-color: transparent;
}

.calc-result {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--brand-dark);
  background: #f0fdfa;
  border: 1px solid #99f6e4;
  border-radius: 12px;
  padding: 16px 18px;
  margin: 0 0 10px;
}

.calc-note {
  font-size: 0.82rem;
  color: var(--muted);
  margin: 0;
}

.glossary dl {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin: 0;
}

.glossary div {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 18px;
}

.glossary dt {
  font-weight: 600;
  color: var(--brand-dark);
  margin-bottom: 4px;
}

.glossary dd {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.preguntas details {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 20px;
  margin-bottom: 12px;
}

.preguntas summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--ink);
}

.preguntas details p {
  margin: 12px 0 0;
  color: var(--muted);
}

.site-footer {
  background: var(--ink);
  color: #c3cdd6;
  padding: 32px 0;
  font-size: 0.9rem;
}

.site-footer p {
  margin: 0 0 8px;
}

.site-footer strong {
  color: #fff;
}

@media (max-width: 640px) {
  .site-header .wrap {
    flex-direction: column;
    gap: 8px;
  }
  .glossary dl {
    grid-template-columns: 1fr;
  }
  section {
    padding: 40px 0;
  }
}