main.css

html {
  font-size: 16px;
  color: #333;
  font-family: sans-serif;
}
body {
  margin: 0;
}
h1 {
  margin: 2rem 0;
  font-size: 2rem;
  line-height: 1.125em;
}
article {
  width: 50rem;
  margin: 0 auto 1rem auto;
  font-size: 1.25rem;
  line-height: 1.5em;
}
.internationalisation {
  width: 75%;
  margin: 0 auto;
  text-align: center;
}
.internationalisation > a {
  margin-left: 2rem;
}
.internationalisation > a:first-of-type {
  margin-left: 0;
}

article > p {
  text-align: justify;
}

.quote {
  font-family: Times, serif;
  font-style: italic;
}

img {
    max-width: 100%;
    height: auto;
    width: auto\9;
}

footer {
  background: #334;
  padding: 1rem 0;
  font-size: 0.875rem;
}
footer .row {
  width: 50rem;
  margin: 0 auto;
  color: #ccc;
}
footer a {
  color: #aaa;
}
@media (max-width: 768px) {
  h1 {
    font-size: 1.5rem;
    text-align: center;
  }
  article {
    font-size: 1.125rem;
  }
  article, footer .row {
    width: 100%;
    box-sizing: border-box;
    padding: 0 0.75rem;
  }
}
#octicon-icon {
  height: 1.25rem;
  width: 1.25rem;
  padding: 0 0.25rem 0 0.5rem;
  fill: #aaa;
  vertical-align: bottom;
}

.dialog-line {
  font-size: 0.9rem;
  line-height: 1.325em;
  margin-bottom: 0.75rem;
}
.dialog-line:last-child {
  margin-bottom: 0;
}
.dialog-line .name {
  width: 7rem;
  float: left;
  padding-top: 0.325rem;
  font-weight: 700;
  line-height: 1.1rem;
  color: #8ca8b4;
  text-align: right;
}
.dialog-line .content {
  position: relative;
  padding: 0.337rem 1.5rem;
  margin: 0 5rem 0 0;
  border-radius: 0.25rem;
}
.dialog-line .content::before {
  position: absolute;
  display: block;
  content: '';
  left: -0.25rem;
  top: 0.625rem;
  width: 0;
  height: 0;
  border-top: 0.25rem solid transparent;
  border-bottom: 0.25rem solid transparent;

  border-right: 0.25rem solid;
}
.dialog-line.-you .content {
  background: #bfe9f9;
}
.dialog-line.-you .content::before {
  border-right-color: #bfe9f9;
}

@media (max-width: 414px) {
  .dialog-line {
    margin-bottom: 1rem;
  }
  .dialog-line .name {
    width: auto;
    float: none;
    text-align: left;
    padding-top: 0;
  }
  .dialog-line .content {
    margin-left: 0;
    margin-right: 0;
  }
  .dialog-line .content::before {
    display: none;
  }
  .dialog-line .time {
    right: 0;
    top: -1rem;
  }
  .dialog-comment {
    margin-bottom: 0.75rem;
    text-align: left;
  }
}