body {
    background-color: #e4e4e4;
    margin: 0 5rem 0 5rem;
    font-family: Verdana, Geneva;
    font-size: 0.625rem;
}

a:link, a:visited {
    text-decoration: none;
    color: #1286ae;
}

a:hover {
    text-decoration: none;
    color: #767676;
}

b {
    color: #044960;
}

h1 {
    font-family: Arial Black, Gadget;
    font-size: 0.9rem;
    letter-spacing: -0.01rem;
    text-transform: uppercase;
    color: #325e6c;
    margin: 0;
    padding: 0;
}

h2 {
    font-family: Arial Black, Gadget;
    font-size: 0.8rem;
    letter-spacing: 0;
    color: #77a3b1;
    margin: 0;
    padding: 0;
}

h3 {
    font-family: Arial Black, Gadget;
    font-size: 0.6rem;
    letter-spacing: 0;
    color: #65adc4;
    margin: 0;
    padding: 0;
}

ul {
    list-style-type: none;
    margin-left: -2rem;
    }

#nav {
    background-color: #cfcfcf;
    max-width: 50rem;
    min-height: 3rem;
    display: flex;
    display: -webkit-flex;
    text-align: center;
    margin: 0.3rem;
    padding: 0;
}

#main {
    display: flex;
    display: -webkit-flex;
    max-width: 50rem;
    min-height: 15rem;
    margin: 0.3rem;
    padding: 0;
}

header {
    background-image: url(../img/headerbg.jpg);
    max-width: 50rem;
    min-height: 8rem;
    display: block;
    border: 0;
    border-style: solid;
    border-bottom-width: 1.8rem;
    border-color: #000;
    margin: 0.3rem;
    padding: 0;
}

footer {
    background-color: #000;
    font-family: Lucida Console, Monaco;
    color: #fff;
    font-size: 0.5rem;
    letter-spacing: 0.1rem;
    line-height: 1rem;
    text-transform: uppercase;
    max-width: 50rem;
    display: block;
    margin: 0.5rem;
    padding: 0;
}

/*propiedades de main*/
#main > article.a {
    background-color: #fff;
    margin: 0.25rem;
    padding: 0.25rem;
    border: 0;
    border-style: solid;
    border-bottom-width: 0.8rem;
    border-color: #006b8f;
    flex: 3 1 20rem;
    -webkit-flex: 3 1 20rem;
}

#main > article.b {
    background-color: #fff;
    margin: 0.25rem;
    padding: 0.25rem;
    border: 0;
    border-style: solid;
    border-bottom-width: 0.8rem;
    border-color: #14a9dc;
    flex: 1 1 10rem;
    -webkit-flex: 1 1 10rem;
}

#main > aside {
    background-color: #fff;
    margin: 0.25rem;
    padding: 0.3rem;
    border: 0;
    border-style: solid;
    border-bottom-width: 0.8rem;
    border-color: #8ac9de;
    flex: 1 1 10rem;
     -webkit-flex: 1 1 10rem;
}

#main > article.ailen {
    background-color: #fff;
    margin: 0.25rem;
    padding: 0.25rem;
    border: 0;
    border-style: solid;
    border-bottom-width: 0.8rem;
    border-color: #006b8f;
    flex: 3 1 20rem;
    -webkit-flex: 3 1 20rem;
}

#main > article.mayra {
    background-color: #fff;
    margin: 0.25rem;
    padding: 0.25rem;
    border: 0;
    border-style: solid;
    border-bottom-width: 0.8rem;
    border-color: #14a9dc;
    flex: 3 1 20rem;
    -webkit-flex: 3 1 20rem;
}

#main > article.andrea {
    background-color: #fff;
    margin: 0.25rem;
    padding: 0.25rem;
    border: 0;
    border-style: solid;
    border-bottom-width: 0.8rem;
    border-color: #8ac9de;
    flex: 3 1 20rem;
    -webkit-flex: 3 1 20rem;
}

img.app {
    width: 100%;
    height: 100%;
    }

/*propiedades de header*/
section.header {
    padding-top: 5rem;
    padding-right: 0.5rem;
    text-align: right;
}

h1.header {
    margin: 0;
    padding: 0;
    font-size: 5rem;
    font-family: Impact;
    color: #000;
    letter-spacing: -0.2rem;
}

h2.header {
    margin: 0;
    padding: 0.3rem;
    font-size: 0.7rem;
    color: #000;
    letter-spacing: 0.2rem;
}

/*propiedades de footer*/
section.footer {
    padding: 0.2rem;
    text-align: justify;
}

/*propiedades de nav*/
ul li.navi {
    display: flex;
    float: left;
    list-style-type: none;
}

li.navi {
    float: left;
    display: block;
    margin: 0.2rem;
}

a.navi:link, a.navi:visited {
    display: block;
    padding: 0.5rem;
    padding-left: 1rem;
    padding-right: 1rem;
    background-color: #000;
    text-decoration: none;
    text-transform: uppercase;
    letter-spacing: 0.2rem;
    color: #ffffff;
}


a.navi:hover {
    display: block;   
    padding: 0.5rem;
    padding-left: 1rem;
    padding-right: 1rem;
    background-color: #62c6e8;
    text-decoration: none;
    text-transform: uppercase;
    letter-spacing: 0.2rem;
    color: #000;
}


/*código query*/

@media all and (max-width: 40rem) {
    body {
    margin: 0 auto 0 auto;
}
    
    #nav {
        flex-flow: column;
         -webkit-flex-flow: column;
        }
    #main {
        flex-flow: column;
         -webkit-flex-flow: column;
        }
}