*{
    box-sizing: border-box;
}
body {
    background-image: linear-gradient(90deg, #7d5fff, #7158e2);
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    overflow: hidden;
    margin: 0;
}

.search {
    height: 50px;
    position: relative;
}
.btn {
    border: 0;
    height: 50px;
    width: 50px;
    font-size: 28px;
    position: absolute;
    top:0;
    left: 0;
    transition: transform 0.5s ease;
}

.input {
    font-size: 18px;
    height: 50px;
    width: 50px;
    padding: 18px;
    transition: width 0.5s ease;
}


.btn:focus ,
.input:focus {
    outline: none;
}

.search.show .input{
    width: 200px;
}
.search.show .btn {
    transform: translateX(200px);
}