html {
  font-family: arial;

}

body {
    background-color: lightyellow;
}

h1 {
  color: red;
  text-align: center;
  margin-right: -150px;
}

h2 {
    color: blue;
}

h3 {
    text-align: center;
    margin-right: -150px;
    color: orange;
    margin-top: -15px;
}

h4 {
    color: purple;
}

#menu {
  float: left;
  position: fixed;
  margin-top: -100px;
  background-color: #d3d3d3;
  border: 2px dashed black
}

main {
    margin-left: 350px;
    background-color: lightblue;
}

span {
    padding-left: 5px
}

html {
  font-family: arial;

}

body {
    background-color: lightyellow;
}

h1 {
  color: red;
  text-align: center;
  margin-right: -150px;
}

h2 {
    color: blue;
}

h3 {
    text-align: center;
    margin-right: -150px;
    color: orange;
    margin-top: -15px;
}

h4 {
    color: purple;
}

#menu {
  float: left;
  position: fixed;
  font-size: 11pt;
  margin-top: -130px;
  background-color: #d3d3d3;
  border: 2px dashed black
}

main {
    margin-left: 350px;
    background-color: lightblue;
}

span {
    padding-left: 5px
}

Change font size of menu
Change font size of menu
