* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

body {
  height: 100%;
  background-color: rgb(87, 82, 82);
}

input[type="text"] {
  padding: 10px;
  font-size: 16px;
  width: 70%;
  border: 0px solid #000;
  background-color: #fff;
  border-radius: 4px;
  margin-right: 10px;
}

.input-el {
  width: 500px;
  margin: 4% auto;
}

.add {
  background-color: rgb(68, 207, 68);
  border: 0px;
  padding: 7px;
  color: #fff;
  font-weight: bold;
  font-size: 16px;
}

.outer-div {
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
  cursor: pointer;
}

.card {
  width: 300px;
  height: 300px;
  background-color: transparent;
  margin-bottom: 20px;
}

.card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.6s;
  transform-style: preserve-3d;
  text-align: center;
}

.card-front,
.card-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  padding: 50px;
  font-size: 42px;
  font-weight: 600;
}

.card:hover .card-inner {
  transform: rotateY(180deg);
}

.card-front {
  background-color: lightcoral;
}

.card-back {
  position: absolute;
  background-color: lightseagreen;
  transform: rotateY(180deg);
  color: #fff;
}