body {
  font-family: 'source_sans_pro', sans;
  margin: 0;
  line-height:  1.5rem;
  font-size: 1rem;
  font-weight: 300;
}
.site {
  max-width: 600px;
  margin: 0 auto;
  padding-left: 20px;
  padding-right: 20px;
}

a {
  color: blue;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

ul {
  padding-left: 2.1rem;
}

nav ul {
  list-style: none;
  padding: 0;
}

nav li {
  display: inline-block;
  margin-right: 10px;
}

article img {
  max-width: 100%;
  height: auto;

}
.bloglist .author {
  display: none;
}
.bloglist li:hover .author {
  display: inline;
}
@media only screen and (max-width: 500px) {
  :root {
    font-size: 90%;
  }
}
@media only screen and (min-width: 500px) and (max-width: 800px) {
  :root {
    font-size: 100%;
  }
}

@media only screen and (min-width: 800px) {
  :root {
    font-size: 120%;
  }
}





body {
  font-family: 'source_sans_pro', sans;
  margin: 0;
  line-height:  1.5rem;
  font-size: 1rem;
  font-weight: 300;
}
h1, h2, h3, h4, h5, h6 {
  font-weight: bold;
}
.site {
  max-width: 600px;
  margin: 0 auto;
  padding-left: 20px;
  padding-right: 20px;
}

a {
  color: blue;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

ul {
  padding-left: 2.1rem;
}

nav ul {
  list-style: none;
  padding: 0;
}

nav li {
  display: inline-block;
  margin-right: 10px;
}

article img {
  max-width: 100%;
  height: auto;

}
.bloglist .author {
  display: none;
}
.bloglist li:hover .author {
  display: inline;
}
@media only screen and (max-width: 500px) {
  :root {
    font-size: 90%;
  }
}
@media only screen and (min-width: 500px) and (max-width: 800px) {
  :root {
    font-size: 100%;
  }
}

@media only screen and (min-width: 800px) {
  :root {
    font-size: 120%;
  }
}





Use bold font for headings. (Just in case, should already be in UAs stylesheets.)
Use bold font for headings.
(Just in case, should already be in UAs stylesheets.)
