:root {
  --primario: #00897b;
  --secundario: #424242;
  --borde: #e0e0e0;
  --fondo: #f9f9f9;
  --card-bg: #ffffff;
  --input-bg: #f5f5f5;
}

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

body {
  font-family: "Roboto", sans-serif;
  background-color: var(--fondo);
  color: var(--secundario);
  display: grid;
  place-items: center;
  min-height: 100vh;
  padding: 1rem;
}

h1,h2,h3,h4 {
  font-family: "Roboto", sans-serif;
  text-align: center;
  color: var(--secundario);
  margin: 0;
  font-weight: 400;
}

#titulo {
  font-size: 1.8rem;
  margin-bottom: 0.25rem;
  color: var(--primario);
  font-weight: 700;
}

#h2 {
  font-size: 1rem;
  margin-bottom: 0.75rem;
  color: var(--secundario);
}

body > * {
  max-width: 500px;
  width: 100%;
}

#banner {
  padding: 1.5rem;
  border-radius: 12px;
  background-color: var(--card-bg);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
  margin-bottom: 1.5rem;
}

#banner h3 {
  font-size: 1rem;
  color: var(--primario);
  margin-bottom: 0.75rem;
  font-weight: 500;
}

#banner ul {
  list-style: none;
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
  gap: 0.5rem;
}

#banner li {
  padding: 0.5rem;
  background-color: var(--input-bg);
  border-radius: 8px;
  text-align: center;
  flex: 1;
  min-width: 120px;
  font-size: 0.9rem;
  font-weight: 500;
}

body > div {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 1.5rem;
  border-radius: 12px;
  background-color: var(--card-bg);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

input,
select {
  width: 100%;
  max-width: 300px;
  padding: 0.75rem;
  margin-bottom: 1rem;
  border: 1px solid var(--borde);
  border-radius: 8px;
  font-size: 1rem;
  background-color: var(--input-bg);
  color: var(--secundario);
  transition: all 0.3s ease;
}

input:focus,
select:focus {
  outline: none;
  border-color: var(--primario);
  box-shadow: 0 0 5px rgba(0, 137, 123, 0.4);
}

button#calcular {
  background-color: var(--primario);
  color: #fff;
  border: none;
  padding: 0.75rem 2rem;
  border-radius: 8px;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 500;
  transition: background-color 0.3s ease;
  width: 100%;
  max-width: 200px;
  margin-top: 0.5rem;
}

button#calcular:hover {
  background-color: #00695c;
}

.boton-historial {
  display: block;
  text-align: center;
  margin-top: 1rem;
  background-color: #424242;
  color: #fff;
  border: none;
  padding: 0.75rem 2rem;
  border-radius: 8px;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 500;
  text-decoration: none;
  transition: background-color 0.3s ease;
  width: 100%;
  max-width: 200px;
}

.boton-historial:hover {
  background-color: #212121;
}

#historial-lista ul {
  list-style: none;
  padding: 0;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
}

#historial-lista li {
  text-align: center;
  min-width: 250px;
}

#historial-lista p {
  text-align: center;
  width: 100%;
}