body {
  max-width: 600px;
  margin: 50px;
  line-height: 1.5;
  text-align: justify;
}
body.dark {
  background: #1a1a1a;
  color: #ccc;
}
body.dark a {
  color: #86c7ff;
}
body.dark a:visited {
  color: #b8a9ff;
}
body.dark a:hover,
body.dark a:focus {
  color: #cfe9ff;
}
body.dark hr {
  border-top-color: #444;
}
#dm {
  position: fixed;
  top: 10px;
  left: 12px;
  font-size: 18px;
  opacity: 0.45;
  cursor: pointer;
  user-select: none;
  transition: opacity 0.2s;
  background: none;
  border: none;
  padding: 0;
  color: inherit;
}
#dm:hover { opacity: 0.85; }

#back-home {
  position: fixed;
  top: 10px;
  left: 38px;
  font-size: 18px;
  opacity: 0.35;
  color: inherit;
  text-decoration: none;
  line-height: 1;
  transition: opacity 0.2s;
}

#back-home:hover,
#back-home:focus {
  opacity: 0.75;
}

@media (max-width: 700px) {
  body {
    max-width: none;
    margin: 16px;
  }

  #dm {
    font-size: 24px;
    top: 8px;
    left: 12px;
  }

  #back-home {
    font-size: 24px;
    top: 8px;
    left: 46px;
  }
}

hr.endline {
    width: 30%; 
    margin: 2em 0; 
    border: none; 
    border-top: 1px solid #aaa;
}
h1, h2, h3, h4, h5, h6 {
    text-align: left;
}
.abstract {
    padding: 1.6em 2em;
    font-family: Georgia, "Times New Roman", serif;
    font-size: 0.95em;
    line-height: 1.7;
    text-align: justify;
    color: inherit;
    border: 1px solid #bbb;
    border-radius: 4px;
    font-style: italic;
    margin: 1.5em 1.5em;
}