h1{
    color:red;
}
h2{
    background-color: cadetblue;
    color: white;
    margin: 0px;
}
h3{
    color: #ef2fac;
    border-bottom: 1px solid;
}
h4{
    color: red;
    text-align: center;
    font-size: 24px;
    border: solid 1px red;
    background-color: white;
}
section{
    border: 1px solid;
    margin: 10px;
    padding: 20px;
}
article{
     border: 4px dotted red;
}
.main{
    width: 750px;
    margin:auto;
}