* {
    font-family: arial;
}

h2 {
    text-align: center;
}

/* Select multiple elements by using a comma */
p, button {
    color: red;
}

/*Selects all inside of descendant*/
#outerDiv p {
    color: blue;
}

/*Selects inside parent (direct descendant)*/
#innerDiv > p {
    color: green;
}

/*Selects all elements placed immediately after an element*/
h3 + p {
    color: blue;
    text-decoration: underline;
}

/*Selects all elements placed immediately before an element*/
p ~ h4 {
    color: orangered;
}