style.css

@import url('https://fonts.googleapis.com/css2?family=Poppins:ital,wght@0,100;0,200;0,300;0,400;0,500;0,600;0,700;0,800;0,900;1,100;1,200;1,300;1,400;1,500;1,600;1,700;1,800;1,900&display=swap');

:root {
    --font-style: "Poppins", sans-serif;
}

* {
    padding: 0;
    margin: 0;
}

html,
body {
    font-family: var(--font-style);
    width: 100%;
    height: 100%;
    background-color: #021427;
}

input {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    font-size: 16px;
    background: transparent;
    width: 25px;
    height: 25px;
    padding: 10px;
    border: solid 3px #1589FF;
    outline: none;
    border-radius: 35px;
    transition: all 0.5s;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 #1589FF;
}

input::placeholder {
    color: #efefef;
    opacity: 0;
    transition: opacity 150ms ease-out;
}

input:focus::placeholder {
    opacity: 1;
}

input:hover {
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 #20047b;
}

input:focus,
input:not(:placeholder-shown) {
    width: 250px;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 #20047b;
}