*{
    padding: 0px;
    margin: 0px;
    box-sizing: border-box;
}
 
header {
    background-color: brown;
}
 
header>h1, header>h2 {
    color: lime;
    text-align: center;
    font-family: Courier, monospace;
    padding: 0px 20px;
}
 
header>h1 {
    font-size: 3rem;
}
 
header>h2 {
    font-size: 2rem;
}
 
nav>ul {
    list-style-type: none;
    display: flex;
    flex-direction: column;
 
}
 
nav>ul>li {
    width: 100%;
    text-align: justify;
}
 
nav>ul>li>a {
    background-color: lightgray;
    display: block;
    text-align: center;
    padding: 10px 0px;
    border: black solid 1px;
}
 
nav>ul>li>a:active {
    background-color: darkgray;
}
 
 
main {
    height: 500px;
    background-color: aquamarine;
}

main > table{
    width: 100%;
}

main> table > tbody > tr > th{
    width: 33%;
}

main> table > tbody > tr:nth-child(odd){
    background-color: yellow;
}

main> table > tbody > tr:nth-child(even){
    background-color: darkgray;
}
 
main > table, 
main> table > tbody > tr> th, 
main> table > tbody > tr> td{
    border: black solid 5px;
    border-radius: 12px;
    border-collapse: collapse;
}

main>article {
    margin: 10px 15px;
}
 
main > article > p{
    text-align: justify;
}
 
footer {
    background-color: lightcyan;
}
 
/* Tablet */
@media screen and (min-width: 600px) {
    header{
        background-color: blueviolet;
    }
 
    nav>ul{
        flex-direction: row;
    }
    main{
        max-width: 700px;
        margin: auto;
    }
 
    footer{
        max-width: 700px;
        margin: auto;
    }
}
 
@media screen and (min-width: 900px){
    body{
        max-width: 1000px;
        margin: auto;
    }
}