/* Reset básico y configuración global */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: "Roboto", "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(180deg, #ffffff, #e3f2fd);
  color: #222222;
  line-height: 1.6;
  scroll-behavior: smooth;
}
/* Enlaces dentro del contenido */
a {
  color: black;
  text-decoration: none;
  transition: color 0.3s, text-decoration 0.3s;
}
a:hover {
  color: black;
  text-decoration: underline;
}
/* Header */
header {
  background: linear-gradient(90deg, #1a73e8, #4285F4);
  color: #ffffff;
  padding: 20px;
  text-align: center;
}
header h1 {
  font-size: 2.5em;
  margin-bottom: 10px;
  text-shadow: 1px 1px 3px rgba(0,0,0,0.3);
}
header p {
  font-size: 1.2em;
}

/* Navegación */
nav {
  background: #ffffff;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
nav ul {
  list-style: none;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  padding: 10px 0;
}
nav ul li {
  margin: 5px 10px;
}
nav ul li a {
  text-decoration: none;
  color: #1a73e8;
  font-weight: 500;
  padding: 8px 16px;
  border-radius: 4px;
  transition: background 0.3s, transform 0.3s;
}
nav ul li a:hover,
nav ul li a.active {
  background: #d2e3fc;
  transform: scale(1.05);
}

/* Secciones */
section {
  margin: 20px auto;
  padding: 20px;
  width: 90%;
  max-width: 1000px;
  background: linear-gradient(180deg, #ffffff, #f8f9fa);
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  transition: transform 0.3s;
}
section:hover {
  transform: translateY(-5px);
}
section h2 {
  margin-bottom: 20px;
  color: #1a73e8;
  border-bottom: 2px solid #1a73e8;
  padding-bottom: 10px;
}

/* Tablas */
table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 20px;
}
table thead th {
  background: #1a73e8;
  color: #ffffff;
  padding: 10px;
  text-align: left;
}
table tbody td {
  padding: 10px;
  border-bottom: 1px solid #dddddd;
}
table tbody tr:hover {
  background: #e8f0fe;
}

/* Botón "Volver arriba" */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: linear-gradient(180deg, #1a73e8, #4285F4);
  color: #ffffff;
  padding: 12px 16px;
  border-radius: 50%;
  text-decoration: none;
  box-shadow: 0 2px 6px rgba(0,0,0,0.3);
  transition: background 0.3s, transform 0.3s;
  z-index: 1000;
}
.back-to-top:hover {
  background: #1558b0;
  transform: scale(1.1);
}

/* Footer */
footer {
  background: #f1f1f1;
  text-align: center;
  padding: 20px;
  color: #222222; /* Color más oscuro para mejor lectura */
}
footer a {
  color: #0066cc; /* Azul accesible con buen contraste */
  text-decoration: none;
  font-weight: 600;
  transition: color 0.3s;
}
footer a:hover {
  color: #004999; /* Azul más oscuro para mejor distinción */
  text-decoration: underline;
}


/* Responsive: Ajustes para dispositivos móviles */
@media (max-width: 768px) {
  nav ul {
    flex-direction: column;
  }
}