h2 {
    text-align: center;
    text-decoration: underline;
    text-shadow: 3px 3px 5px #444444;
    font-family: "맑은 고딕";
    font-size: 30px;
}

p {
    line-height: 150%;
    font-family: "돋움";
}

#rosemary {
    background-color: pink;
    width: 50%;
    float: left;
}

#rosemary p {
    background-color: orange;
    padding: 20px;
    margin: 20px;
}

#rosemary img {
    display: block;
    margin-left: auto;
    margin-right: auto;
    padding: 10px;
}

#hydrogen {
    background-color: skyblue;
    margin-top: 20px;
    padding: 10px;
    width: 50%;
    display: block;
    float: left;
}

#hydrogen h2 {
    color: blue;
}

#hydrogen p {
    background-color: wheat;
    padding: 20px;
    margin: 20px;
    border: solid 1px black;
}

#bold {
    font-weight: bold;
    font-style: italic;
}

#hydrogen-img {
    background-color: white;
    display: block;
    border: 1px solid black;
}

#sidebar {
    float: left;
    display: block;
    margin: 0px;
    padding: 0px;
    list-style-type: none;
}

#link {
    text-align: center;
    text-decoration-line: none;
    background-color: #999999;
    width: 100px;
    padding: 16px;
    float: left;
    color: white;
}

#link:hover {
    background-color: gray;
}

.container {
    float: left;
}

.container::after {
    content: '';
    display: table;
    clear: both;
}