index.css

.inbox {
  flex: 1;
}
.inbox .item {
  display: flex;
  border-top: 1px solid #ddd;
  padding: 0.5rem 0;
  color: #555;
  align-items: center;
}
.inbox .item:hover {
  background: #fafafa;
}
.inbox .item .source {
  flex: 0 0 120px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.inbox .item .source a {
  color: #555;
}
.inbox .item .title {
  flex: 1;
}
.inbox .item .pubdate {
  font-size: 13px;
}
.inbox .intro {
  background: #fafafa;
  padding: 1rem 2rem;
  color: #666;
}
.sources-list {
  flex: 0 0 300px;
  margin-right: 1rem;
  border: 1px solid #ccc;
  border-radius: 3px;
}
.sources-list form {
  display: flex;
}
.sources-list input {
  flex: 1;
  padding: 0.3rem 0.4rem;
  font-size: 14px;
  font-weight: 100;
  border: 0;
  border-bottom: 1px solid #ddd;
  border-radius: 3px 0px 0px 0;
}
.sources-list button {
  background: #eee;
  border: 0;
  border-left: 1px solid #ddd;
  border-bottom: 1px solid #ddd;
  border-radius: 0 3px 0 0;
  color: #666;
  padding: 0 0.5rem;
}
.sources-list .source {
  padding: 0.3rem 0.4rem;
  border-bottom: 1px solid #ddd;
  max-width: 287px;
  overflow: hidden;
  text-overflow: ellipsis;
}
.sources-list .source:last-child {
  border: 0;
}
.sources-list .source .remove {
  float: right;
  cursor: pointer;
  color: #989494;
  font-weight: bold;
}
.sources-list .source .error {
  color: #c00;
  font-size: 12px;
}
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Ubuntu, Cantarell, "Oxygen Sans", "Helvetica Neue", sans-serif;
}
main {
  display: flex;
  align-items: flex-start;
}
h1 small {
  font-size: 14px;
  font-weight: 100;
}
a {
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}