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

input {
    height: 50px;
    font-size: 19px;
    padding: 10px;
    width: 0px;
    background-color: #fff;
    border: 0px;
    

}

button {
    background-color: #fff;
    border: 0;
    cursor: pointer;
    font-size: 24px;
    position: absolute;    
    height: 70px;
    width: 50px;
    transition: transform 0.3s ease;
    
}
input,
button {
    outline: none;
}
.buscar.active .input{
    width: 200px;
}