style.css

.container-button {
  max-width: 1138px;
  height: 50px;
  margin: 0 auto;
}

.container-flex {
  max-width: 1138px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
}

table {
  margin: 0 0 20px;
}

#usersTable table,
th,
td {
  border: 1px solid black;
}

th,
td {
  padding: 5px;
}

.button-delete {
  background-color: red;
}

.add-user {
  float: right;
}

input {
  width:100px;
}

.red-border {
  border: 1px solid red;
}

img.avatar {
  max-width: 100px;
}

.button {
  border: 1px solid black;
  border-radius: 3px;
  width: fit-content;
  padding: 10px;
  margin: 10px;
}

.to-top-button {
  display: none; 
  position: fixed;
  bottom: 20px; 
  right: 30px; 
}

.to-bottom-button {
  display: block; 
  position: fixed; 
  top: 20px; 
  right: 30px; 
}