body {
    background-size: 100vw 100vh;
    background-attachment: fixed;
    margin: 0;
}
body.numeros-reales {
    background-image: url("../img/pi.jpg");
}

body.geometria {
    background-image: url("../img/geo.jpg");
}

body.funciones {
    background-image: url("../img/func.webp");
}

body.polinomios {
    background-image: url("../img/poli.jpg");
}

body.trigonometria {
    background-image: url("../img/trigo.webp");
}

body.exponenciales-logaritmos {
    background-image: url("../img/expo.jpg");
}

body.vectores {
    background-image: url("../img/vector.jpg");
}

body.cinematica-estatica {
    background-image: url("../img/cine-esta.jpg");
}

body.dinamica {
    background-image: url("../img/avion2.jpg");
}

body.fluidos {
    background-image: url("../img/fluidos.jpg");
}

body.electricidad {
    background-image: url("../img/electro.jpg");
}

body.optica {
    background-image: url("../img/prisma.jpeg");
}

#ingen .titulo,
#ingen .oferta,
#ingen .pie {
    box-sizing: border-box;
    width: 95%;
}
#ingen .oferta strong,
#ingen .pie strong {
    font-weight: 600;
}
#ingen .titulo {
	text-align: center;
	border-radius: 40px;
	max-width: 374px;
	font-size: 20px;
	background: rgba(253,237,201,1);
	margin: 70px auto 0px auto; 
	padding: 0px;
    border-style: solid;
    border-color:#966245;
    padding-bottom: 40px;
}
#ingen .titulo h1 {
    margin: 0;
    padding: 10px 8px 4px;
    font-size: 21px;
    font-weight: bold;
    text-decoration: underline;
}
#ingen .titulo .numero-curso {
    margin: 0 0 10px;
    padding: 0 8px;
    font-size: 16px;
    font-weight: 600;
}
#ingen .titulo iframe {
    display: block;
    width: 100%;
    max-width: 368px;
    height: auto;
    aspect-ratio: 16 / 9;
    margin: 0 auto;
}
#ingen .oferta {
	border-radius: 40px;
	text-align: left;
	max-width: 960px;
	font-size: 18px;
	background: rgba(253,237,201,1);
	margin: 20px auto; 
	padding: 20px;
    border-style: solid;
    border-color: #966245;

}
#ingen .oferta h2 {
    margin: 25px 0 10px;
    padding: 0;
    font-size: 20px;
    font-weight: bold;
    text-align: center;
}

#ingen .oferta h2:first-child {
    margin-top: 0;
}

#ingen .oferta p {
    margin: 0 0 16px;
    padding: 0;
    font-size: 19px;
    font-weight: 300;
}

#ingen .oferta a{
  font-weight: bold;
  text-decoration: none;
}
#ingen a:link {
    color: blue;
}

#ingen a:visited {
    color: blue;
}

#ingen a:hover {
    color: darkred;
}
#ingen .pie {
	border-radius: 40px;
	text-align: center;
	max-width: 960px;
	font-size: 16px;
	background: rgba(253,237,201,1);
	margin: 20px auto; 
	padding: 20px;
    border-style: solid;
    border-color: #966245;

}

#ingen .pie h2 {
    margin: 0 0 12px;
    padding: 0;
    font-size: 20px;
    font-weight: bold;
}

#ingen .pie p {
    margin: 0;
    font-size: 17px;
    font-weight: 300;
}
#ingen .oferta h2,
#ingen .pie h2 {
    text-decoration: underline;
    text-decoration-thickness: 3px;
    text-underline-offset: 6px;
}