*{
    margin: 0; padding: 0;
}

/*type selector*/
body{
    background-color: #234;
    color: #eee;
    font-family: verdana, arial, sans-serif;
    padding: 12px;
    border: 8px solid #222;
    padding-bottom: 800px;
    margin: 4px;
    padding: 12px;
}

header{
    background-color: #222;
    text-align: center;
    padding: 12px;
}

/* descendent selector*/
header h1{
    text-align: center;
    font-weight: normal;
    text-transform: uppercase;
    color: yellowgreen;
    padding-bottom: 20px;
    margin-bottom: 20px;
    border-bottom: 2px solid hotpink;
}

/* */
header span{
    display: block;
    border: 0px;
    color: #ff4;
}

/* class selector */
.subtitle{
    text-align: center;
    border: 2px solid #222;
    padding: 10px;
    line-height: l.5;
    text-transform: lowercase;
    letter-spacing: 8px;
}

/* adjacent selector*/
header + p{
    display: none;
}

/* CSS Examples */
section{
    display: flex;
    justify-content: center;
    flex-flow: row wrap;
}

section article{
    border: 2px solid hotpink;
    max-width: 360px;
    min-height: 200px;
    margin: 10px;
    flex: 0 0 auto;
    padding: 4px;
}

article h2{
    font-size: 16pt;
    text-align: center;
}

article p{
    margin: 8px;
    line-height: 1.4;
    text-align: center;
}

/* ID selector */

#art1 div{
    width: 70%;
    aspect-ratio: 2/1;
    background-color: skyblue;
    margin: 20px auto;
    border-radius: 20px;
}

#art2 div{
    width: 70%;
    aspect-ratio: 2.5/1;
    background-color: #000;
    margin: 20px auto;
    box-shadow: -4px 8px 15px white;
    border-radius: 20px;
}

#art3 h2{
    font-family: "Caveat", cursive;
    font-size: 28pt;
    text-align: center;
    color: #ff3;
}

#art4 {
    /* use position relative on the parent*/
    position: relative;
}

#art4 h2{
    color: #ff3;
    /* use position absolute on the child you want to manipulate */
    position: absolute;
    bottom: 0; right: 0;
    border: 0px solid yellowgreen;
    width: 100%;
    padding-bottom: 10px;
}

#art5 {
    position: relative;
}

#art5 div{
    position: absolute;
}

#art5 div:nth-of-type(1){
    width: 35%; aspect-ratio: 1;
    background-color: #f44;
    bottom: 0px; left: 60px;
    z-index:10;
}

#art5 div:nth-of-type(2){
    width: 35%; aspect-ratio: 1;
    background-color: #44f;
    bottom: -30px; right: 60px;
    z-index:5;
}

#art6{
    transition: all 300ms linear;
}

/* psuedo element */
#art6:hover{
    background-color: #404;
    color: #ff4;
    border: 2px solid yellowgreen;
}







/* css ruleset, aka rule:
selector {
    declaration1;
    declaration2;
    property: value:
    e.g property: value1, value2, value3;
        property: value value;
}
*/