index.css

body {
  background-color: #6c8085;
  color: white;
  text-align: center;
  line-height: 200%;
}

.js-toDoList {
  list-style: none;
}

button {
  background: rgba(0, 0, 0, 0);
  border-color: transparent;
  cursor: pointer;
}
.js-form {
  font-size: 150%;
  margin-bottom: 30pt;
}
input {
  background: rgba(0, 0, 0, 0);
  border-color: transparent;
  font-size: 150%;
  text-align: center;
  color: white;
}
input::placeholder {
  color: white;
  text-decoration: underline;
}

h1 {
  font-size: 700%;
}

h4 {
  font-size: 50px;
}

.form,
.greetings {
  display: none;
}

.showing {
  display: block;
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.bgImage {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  animation: fadeIn 0.5s linear;
}