index.css

body {
  background: whitesmoke !important;
}

* {
  box-sizing: border-box;
}

ul {
  padding: 1% 5% !important;
  list-style: none;
}

ul li {
  border-radius: 10px;
  margin: 10px;
  cursor: pointer;
  position: relative;
  padding: 15px 20px;
  background: #d6d6d6;
  font-size: 18px;
}

.close {
  position: absolute;
  right: 0;
  top: 0;
  padding: 18px;
  border: none;
  background: transparent;
}

.close:hover {
  background-color: #f44336;
  color: white;
  height: 100%;
}

.header {
  background-color: rgb(49, 49, 49);
  padding: 30px 40px;
  color: white;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

h2 {
  margin: 5px;
}

.addField {
  width: 70%;
}

input {
  border: none;
  width: 75%;
  padding: 10px;
  float: left;
  font-size: 16px;
}

.addBtn {
  padding: 10px;
  width: 25%;
  float: left;
  cursor: pointer;

  background: #979797;
  color: white;
}

.addBtn:hover {
  background-color: #29c6b6;
}