styles.css

body {
    font-family: 'Roboto';
    margin: 0;
    background-color: rgba(244,241,234,0.5);
    display: grid;
    grid-template-rows: 56px 1fr;
    grid-template-columns: 270px 1fr;
    grid-template-areas: "header header"
                         "sidebar content";
}

.top-nav {
    grid-area: header;
}

.user-activity {
    grid-area: sidebar;
}

.page-content {
    display: flex;
    grid-area: content;
}

.reading-challenge {
    padding: 8px;
}

.currently-reading section img {
    max-height: 100%;
    width: 120px;
    margin-right: 8px;
}

.currently-reading section {
    display: flex;
    flex-direction: row-reverse;
    align-items: flex-start;
    border-bottom: solid 1px #aaa;
    height: 200px;
    padding: 8px;
}

.user-activity {
    display: flex;
    flex-direction: column;
    border-right: solid 1px #aaa;
    background-color: white;
    grid-area: sidebar;
}

.user-activity > header {
    border-bottom: solid 1px #aaa;
    padding: 8px;
}

.top-nav {
    height: 56px;
    padding: 12px 64px;
    border-bottom: solid 1px #aaa;
    box-sizing: border-box;
    display: flex;
    align-items: center;
    background-color: #F4F1EA;
    grid-area: header;
}

.top-nav h1 {
    font-size: 24px;
    color: #444;
    display: inline-block;
}

.supplemental-links ul {
    display: inline-block;
    margin: 0;
}

.supplemental-links a {
    text-decoration: none;
    color: hsl(200, 70%, 45%);
}

.supplemental-links li {
    float: left;
    margin-left: 24px;
    text-decoration: none;
    list-style: none;
}


.profile {
    display: inline-block;
    margin-left: auto;
}
.news-feed {
    display: flex;
    flex-direction: column;
    margin: 16px 80px;
}

.news-feed article {
    border: solid 1px #aaa;
    border-radius: 4px;
    padding: 8px;
}

.news-feed input {
    width: 100%;
    padding: 8px;
    margin-top: 8px;
    border-radius: 4px;
    border-color: black;
    border-width: 1px;
}

.news-feed .review {
    margin: 16px 0;
    border-radius: 4px;
    border: solid 1px #aaa;
}

.news-feed article {
    background-color: white;
}

.news-feed .review header {
    border-bottom: solid 1px #aaa;
    padding: 16px;
}

.news-feed .review img {
    margin-right: 8px;
    max-width: 140px;
}

.review-body {
    padding: 16px 16px;
    display: flex;
}

.comment-footer {
    padding: 8px;
    border-top: solid 1px #aaa;
}

.news-feed .review header [user], .news-feed .review header [book] {
    font-weight: bold;
}