body {
    margin: 0px;

    background: linear-gradient(transparent, grey);
}

#fondoArriba {
    position: absolute;

    width: 100%;

    height: 275px;

    background-color: rgb(245, 245, 245);

    z-index: -1;
}

#fondoAbajo {
    position: absolute;

    width: 100%;

    top: 275px;

    height: 140%;

    background-color: rgb(230, 230, 230);

    z-index: -1;
}

#barraArriba {
    width: 100%;

    height: 50px;

    position: fixed;

    background-color: white;

    z-index: 1;
}

#botónPáginaPrincipal {
    display: block;

    box-sizing: border-box;

    background-image: url(ImágenesPsymulations/mariposa.png);

    background-size: cover;

    border-radius: 4px;

    width: 50px;

    height: 50px;

    position: absolute;

    top: 5px;

    left: 40px;
}

#textoTítuloPsymulations {
    position: relative;

    left: 50px;

    bottom: 5px;

    font-size: 20px;
}

ul {
    border-bottom: 1px solid black;

    box-shadow: 0px 0px 5px 2px;

    background-color: white;

    height: 60px;

    margin-top: 0px;
}

#botonesArriba {
    width: 500px;

    height: 100%;

    margin: auto;

    border: 0px;
}

li {
    box-sizing: border-box;

    display: inline-block;

    padding: 2px;

    height: 100%;

    width: 110px;

    font-size: 17px;

    margin-top: 8px;

    margin-right: 10px;

    text-align: center;
}

#botónContacto {
    position: relative;

    bottom: 10px;
}



h1 {
    box-sizing: border-box;

    color: rgb(60, 60, 60);

    text-align: center;

    font-size: 60px;

    font-family: Times;

    font-style: italic;

    width: 700px;

    margin-left: 230px;

    margin-right: 120px;

    margin-top: 100px;
}



h2 {
    box-sizing: border-box;

    width: 500px;

    font-style: italic;

    color: rgb(55, 120, 150);

    margin: 20px;

    margin-left: 0px;

    font-size: 40px;
}

p {
    box-sizing: border-box;
}

.meterTextoFormulario {
    border: none;

    background: rgb(231, 231, 231);
}

#imagenUno {
    display: block;

    box-sizing: border-box;

    border-radius: 4px;

    width: 550px;

    height: 305px;

    background-image: url(ImágenesPsymulations/ImagenSimulaciónSelva.png);

    background-size: cover;

    margin-top: 30px;

    padding-top: 0px;

    margin-left: 100px;
}

#imagenDos {
    display: block;

    box-sizing: border-box;

    border-radius: 4px;

    width: 550px;

    height: 305px;

    background-image: url(ImágenesPsymulations/ImagenSimulaciónHabitación.png);

    background-size: cover;

    margin-top: 30px;

    margin-left: 100px;
}

.recuadroTexto {
    box-sizing: border-box;

    width: 500px;

    border-radius: 4px;

    padding: 20px;

    position: relative;

    bottom: 100px;

    margin-left: 40px;
}

.textoRecuadroGris {
    margin-right: 40px;
}

.izquierdaDerecha {
    display: inline-block;
}

.izquierdaDerecha2 {
    display: inline-block;
}

.izquierdaDerecha3 {
    display: inline-block;
}

a {
    text-decoration: none;

    color: black;
}