* {
    box-sizing: border-box;
}

:root {
    --color0: white;
    --color1: #EFECE3;
    --color1a: #fcfcfc;
    --color2: #8FABD4;
    --color3: #4A70A9;
    --color4: #000000;
    --altos: 85px;
    --padding10: 10px;
}

body {
    background-color: var(--color1);
    padding: 0px;
    margin: 0px;
    font-family: Arial, Helvetica, sans-serif;
    display: grid;
    grid-template-rows: var(--altos) auto 150px;
}

header {
    background-color: var(--color3);
    color: var(--color1);
    padding-top: calc((var(--altos) - 1.2em) / 2);
}

header ul {
    list-style: none;
    padding: 0px;
    margin: 0px;
    text-align: center;
}

header ul li {
    display: inline-block;
}

header ul li a {
    color: inherit;
    text-decoration: none;
    display: inline-block;
    margin-right: 50px;
    font-size: 1.2em;
}

header ul li a:hover {
    color: var(--color0);
}

main {
    display: grid;
    grid-template-columns: 4fr 1fr;
    max-width: 1250px;
    margin: auto;
    gap: var(--padding10);
    background-color: var(--color0);
}

#filtrar {
    background-color: var(--color2);
    padding: var(--padding10);
    display: grid;
    grid-template-columns: 45% 45% calc(10% - (var(--padding10) * 2));
    gap: var(--padding10);
    margin-left: calc(var(--padding10) * 2);
    margin-top: calc(var(--padding10) * 2);
    margin-bottom: var(--padding10);
    border-radius: 5px;
}

#filtrar select {
    font-size: 1.2em;
    border-radius: 4px;
}

#filtrar button {
    background-color: var(--color3);
    border: 0px;
    font-size: 1.5em;
    color: var(--color1);
    border-radius: 3px;
}

main>nav {
    background-color: var(--color2);
    color: var(--color0);
}


main>nav ul {
    list-style: none;
    margin: 0px;
    padding: 0px;
}

main>nav ul a {
    color: inherit;
    text-decoration: var(--color3);
    display: inline-block;
    margin: var(--padding10);
}

#principal>section {
    padding: calc(var(--padding10) * 2);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--padding10);
}

#principal>section>article {
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-template-rows: auto auto auto;
    gap: var(--padding10);
    grid-template-areas: "titulo titulo"
        "texto imagen"
        "nada boton";
    background-color: var(--color1a);
    padding: var(--padding10);
    border-radius: 4px;
    align-items: center;
}

#principal>section>article>h2 {
    grid-area: titulo;
    margin-top: 4px;
    margin-bottom: 4px;
}


#principal>section>article>p {
    grid-area: texto;
}

#principal>section>article>img {
    grid-area: imagen;
    max-width: 100%;
    border-radius: 4px;
}

#principal>section>article>div {
    grid-area: boton;
    text-align: right;
}


#principal>section>article>div a {
    display: inline-block;
    background-color: var(--color2);
    color: var(--color0);
    padding: var(--padding10);
    text-decoration: none;
    border-radius: 3px;
}

footer>div {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    padding-left: 150px;
    padding-right: 150px;
    padding-top: var(--padding10);
    padding-bottom: var(--padding10);
    gap: calc(var(--padding10) * 3);
    background-color: var(--color4);
}

footer img {
    max-width: 100%;
}



@media (max-width: 800px) {

    body {
        grid-template-rows: repeat(3, auto);
    }

    header {
        padding: var(--padding10);
    }

    header ul {
        text-align: right;
    }

    header ul li {
        display: block;
    }

    main {
        grid-template-columns: 100vw;
        max-width: 100%;
        width: 100%;
    }

    #filtrar {
        grid-template-columns: 100%;
        gap: var(--padding10);
        margin: 0px;
        border-radius: 0px;
    }

    #principal>section {
        padding: var(--padding10);
        grid-template-columns: 100vw;
        gap: var(--padding10);
    }

    #principal>section>article {
        grid-template-columns: 25% 75%;
        grid-template-rows: auto auto;
        gap: var(--padding10);
        grid-template-areas: "imagen titulo"
            "imagen boton";
        background-color: var(--color1a);
        padding: var(--padding10);
        border-radius: 4px;
        align-items: center;
    }

    #principal>section>article h2{
        font-size: 1.3em;
    }

#principal>section>article>div {
    margin-right: calc(var(--padding10) * 3) ;
}

    footer {
        display: none;
    }

    #principal>section>article>p {
        display: none;
    }

}