styles.css

html {
  height: 100%;
}
body {
  background-color: white;
  padding: 16px;
  margin: 0;
  height: 100%;
  box-sizing: border-box;
}

body, input, button {
  font-family: 'Titillium Web', sans-serif;
}

.root {
  display: flex;
  flex-direction: column;
  height: 100%;
}

.messages {
  flex: 1;
  margin-bottom: 66px;
}

.message-wrapper {
  display: flex;
}

.message {
  margin-bottom: 16px;
  color: white;
  padding: 4px 8px;
}

.bot-message .message {
  background-color: purple;
}

.bot-message .message-variant {
  background-color: rgb(186, 115, 230);
}

.message-continuing {
  margin-top: -16px;
}

.self-message {
  justify-content: flex-end;
}

.self-message .message {
  background-color: grey;
}

.self-message .message-variant {
  background-color: black;
}

form {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background-color: grey;
  padding: 16px;
}

.bottom-bar {
  display: flex;
}

.username {
  margin-right: 8px;
}

.username input {
  width: auto;
}

.message-input {
  flex: 1;
}

.message-input input {
  width: 100%;
  box-sizing: border-box;
}

.button {
  margin-left: 8px;
}

button, input {
  border: 0;
  outline: 0;
  background-color: white;
  color: black;
  font-size: 16px;
  padding: 4px 8px;
}

button {
  cursor: pointer;
}

input:focus, button:focus {
  background-color: black;
  color: white;
}

.username-measure {
  position: absolute;
  visibility: hidden;
}