html,
body {
  min-width: 290px;
  color: #4d4e53;
  background-color: #6cffda;
  font-family: 'Open Sans', Tahoma, sans-serif;
  line-height: 1.5;
}

#navbar {
    position: fixed;
    min-width: 290px;
    top: 0px;
    left: 0px;
    width: 300px;
    height: 100%;
    border-right: solid;
    border-color: rgba(255, 51, 0, 0.4);
  }
  header {
    color: rgb(255, 0, 0);
    font-size: 2.1em;
    font-weight: bold;
  }
  #navbar ul {
    height: 88%;
    padding: 0;
    overflow-y: auto;
    overflow-x: hidden;
  }
  
  #navbar li {
    color: #4d4e53;
    border-top: 1px solid;
    list-style: none;
    position: relative;
    width: 100%;
  }
  
  #navbar a {
    display: block;
    padding: 10px 30px;
    color: #4d4e53;
  }
  #main-doc {
    position: absolute;
    margin-left: 400px;
    margin-right: 600px;
    padding: 20px;
    margin-bottom: 110px;
    text-align:justify;
    font-size: large;
  }

  .box {
    width: 50%;
    margin: 0 auto;
    padding: 20px;
    background-color: rgb(250, 236, 236); 
    border-radius: 10px; 
  }

      #navbar li a {
        text-decoration: none;
        color: #3700ff; 
        font-size: 20px;
        font-family: Arial, sans-serif;
        font-weight: 600;
      }

      @media (max-width: 768px) {
        body {
          font-size: 14px;
        }
      
        .header {
          text-align: center;
        }
      }