body {
  font-family: Arial, "Arial", sans-serif;
  margin: 0;
  font-size: 18px;
  line-height: 1.3em;
}

h1, h2, h3, h4, h5 {
  font-family: Arial, "Arial", sans-serif;
}

:root {
  --light: #f5f5f5;
  --dark: #18120d;
}

video {
  width: 80%;
  line-height: 0px;
  vertical-align: bottom;
}

/* light mode*/

body {
  background-color: #ffffff;
  color: var(--dark);
}

a:link {
  color: var(--dark);
}

a:visited { 
  color: var(--dark);
}

/* */

main {
  max-width: 500px;
  max-height: 95vh;
  padding: 5px;
}

.leftcolumn {
  flex: 1 1 64%;
  vertical-align: top;
}
.rightcolumn {
  flex: 1 1 36%;
  vertical-align: top;
  overflow-y: auto;
  text-align: justify;
}

/* dark mode */

@media (prefers-color-scheme: dark) {
  body {
    background-color: var(--dark);
    color: var(--light);
  }
  a:link {
    color: var(--light);
  }
  a:visited {
    color: var(--light);
  }
}

/* screenwidth */
@media screen and (max-width: 1024px) {
  .main {
      display:block;
  }
}