style.css

#package {
  background: #66FFFF;
  border: 2px;
  margin: 0 auto;
  width: 600px;

}
#chatlogPackage {
  background: #FFFFFF;
  border: 1px;
  margin: 0 auto;
  width: 400px;
  height: 400px;
  margin-bottom: 50px;
  scroll-behavior: auto;
  overflow: auto;
  box-sizing: border-box;
  padding-bottom: 120px;
}
.right {
  
  float: right;
  background-color: green;
  border-radius: 15px;
  display: block; 
  clear:both;
  padding: 10px ;
  margin-left: 200px;
  margin-right: 20px;
}

.left {
 
  float: left;
  border-radius: 15px;
  background-color: yellow;
  display: block; 
  clear:both;
  padding: 10px;
  margin-right: 200px;
  margin-left: 20px;
}

#usermessage {
  width: 400px;
  margin-left: 98px;
  margin-bottom: 50px;
  float: top;
}

h1 {
  margin-left: 100px;
  margin-top: 50px;
}

#chatting {
  text-align: right;
}