body {
    background: #3EA1FF repeat;
    
}
header h1{
    color:orange;
    text-align: center;
    font-size: 3em;
}


header h3 {
    margin 60px;
    padding: 10px;
    background-color: orange;
    border-radius: 20px;
    opacity: 0.8;
    text-align: center;
    color: blue;   
}

#introduccion h4 {
    margin: 40px;
    padding: 10px;
    text-align: center;
    color: orange;
    font-size: 2em;
}

 h5 {
    text-align: center;
    color: orange;
    font-size: 2em;
}
    

#complejos {
    margin-left:350px;
    margin-right: 350px;
    padding: 2px;
    background-color: orange;
    opacity: 0.7;
    border-radius: 20px;
    text-align: center;   
    border: 10px solid black;
}


header h45 {
    margin 60px;
    padding: 10px;
    background-color: orange;
    border-radius: 20px;
    opacity: 0.8;
    text-align: center;
    color: blue;   
}

#complejos input {
    background-color: powderblue;
    border: 2px solid black;
    border-radius: 20px;
    font-style:italic;
  
}

#introduccion1 h6 {
    margin: 40px;
    padding: 10px;
    text-align: center;
    color: orange;
    font-size: 2em;
}


    

#complejo {
    margin-left:350px;
    margin-right: 350px;
    padding: 2px;
    background-color: orange;
    opacity: 0.7;
    border-radius: 20px;
    text-align: center;   
    border: 10px solid black;
}



#complejo input {
    background-color: steelblue;
    border: 2px solid black;
    border-radius: 20px;
    font-style:italic;
  
}

#operaciones {
    margin-left: 300px;
    margin-right: 300px;
    background-color: orange;
    opacity:0.7;
    border-radius: 20px;
    text-align: center;
    font-size: 140%;
     border: 10px solid blue;

}

#operaciones h6 {
    text-align: center;
    color: black;
    font-size: 1em;
}

button {
    border-radius: 20px;
    font-size: 20px;
    border-color: black;
    color: black;
}

footer {
    background-color: orange;
    margin: 20px;
    border-radius: 20px;
    height: 2em;
    
}


footer p {
    text-align: center;
    font-size: 100%;
}