* {
    box-sizing: border-box;
}

body {
    font-family: Arial, Helvetica, sans-serif;
    max-width: 800px;
    margin: auto;
}

section {
    margin: 100px 0;
}

/* Section 1 */
#section1 a,
#section1 a:link {
    color: blue;
}

#section1 a:hover,
#section1 a:focus {
    text-decoration: none;
}

#section1 a:active,
#section1 a:visited {
    color: red;
    text-decoration: none;
}



/* Section 2 */
#section2 p:nth-of-type(even) {
    font-weight: bold;
    color: teal;
}

#section2 p:first-letter {
    font-size: 1.5rem;
    font-weight: bold;
    color: brown;
}


/* Section 3 */
#section3 input {
    font-size: 1.3em;
    width: 500px;
    border-radius: 4px;
    border: solid 3px transparent;
    background-color: #F0F0F0;
    line-height: 2em;
    margin-bottom: 20px;
    padding: 4px 15px;
}

#section3 input:focus {
    background-color: yellow;
    border: solid 3px hotpink;
    outline: none;
}


/* Section 4 */
.new::before {
    content: "new";
    text-transform: uppercase;
    font-size: 0.8em;
    padding: 3px 6px;
    background-color: hotpink;
    margin-right: 5px;
    color: white;
    font-weight: bold;
    border-radius: 3px;
}

/* requires that you include the font-awesome stylesheet */
#section4 .comment::before {
    font-family: "Font Awesome 5 Free";
    font-weight: 400;
    content: "\f075";
    margin-right: 5px;
}



.card-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    column-gap: 20px;
}

.card {
    width: 100%;
    height: 250px;
    background-color: #F0F0F0;
    padding: 10px;
}

.card button {
    display: none;
}

.card:hover button,
.card:focus button,
.card:focus-within button {
    display: inline-block;
}