style.css

/* iniciando css */

body{
    font-family: verdana;
}

header{
    text-align: center;
    margin-bottom: 40px;
}

main{
    border: 2px solid black;
    margin: 10px;
    padding: 10px;
    font-family: Arial;
    overflow: hidden;
}

*::selection{
    background-color: darkblue;
    color: lightblue;
}

h1::selection{
    background-color: cadetblue;
    color: aqua;
}

h2::selection{
    background-color: green;
    color: greenyellow;
}

h3::selection{
    background-color: brown;
    color: yellow;
}

h4::selection{
    background-color: red;
    color: orange;
}

h5::selection{
    background-color: purple;
    color: pink;
}

h6::selection{
    background-color: indigo;
    color: lightcoral;
}

.iframe{
    height:50vw;
    width:100;
    align-items: center;
}

figure{
    border: 2px solid black;
    align-items: center;
    overflow: hidden;
}

div{
    padding-left: auto;
    padding-right: auto;
}

img{
    background-size: cover;
    clear: both;
    max-width: 100%;
    max-height: 100%;
    left: 50%;
}

iframe{
    max-width: 100%;
}