* { box-sizing: border-box;
    color: rgb(247, 248, 253);
    font-family: Arial;
}

body {background-color: rgb(42, 43, 47);}
h1 {background-color:rgb(54,57,64);
    text-align: center;}
p {font-size: 16px;}
.btnTheme {background:rgb(64,70,75);
    text-align: center;}

ol > li {list-style-type: upper-roman;}

/*---links---*/
a:link {color:rgb(88, 101, 242);}
a:visited {color:rgb(118, 119, 124);}
a:hover {color:rgb(116, 121, 177);}
a:active {color:blue;}

/*---tables---*/
table {
    margin: 10px; 
    padding: 10px;
    border: 5px solid rgb(33, 34, 38);
    border-collapse: collapse;
}
tr, td, th {
    border: 2px solid rgb(33, 34, 38);
    text-align: left;
}
tr:nth-child(even) {background-color: rgb(48, 49, 54);}

/*---Flex Boxes---*/
.flex-container {
    display: flex;
    flex-direction: row;
    justify-content: center;
    align-content: stretch;
    flex-wrap: wrap;
}
.flex-container > div {
    background-color: rgb(54,57,64);
    width: 400px;
    margin: 10px;
    text-align: center;
    font-size: 16px;
}